Biotransformation pathway, growth inhibition, and biochemical response of Scenedesmus obliquus to brilliant green dye: Implications for bioremediation
Rajamanickam R., Selvasembian R.
Article, Biochemical Engineering Journal, 2026, DOI Link
View abstract ⏷
The potential of live microalgae Scenedesmus obliquus was tested for removing Brilliant green dye (BGD). BGD is a cationic dye that has been widely used as a colouring agent in various sectors, but this dye has been reported in wastewater due to its high solubility in water. Scenedesmus obliquus is one of the most widely employed microalgae species with good bioremediation potential and biochemical composition. This study reports growth inhibition of Scenedesmus obliquus in test runs 5 mg/L (17 %), 10 mg/L (31 %), 25 mg/L (42 %), and 50 mg/L (57 %), and the EC50 value was predicted to be 33.7 mg/L using probit statistical analysis. The removal efficiency decreased from 99 % to 87 % as the BGD concentration increased, and the removal mechanism was reported in the order of biodegradation > bioaccumulation > bioadsorption. The biodegradation potential decreased from 97 % to 84 % at the BGD concentration of 50 mg/L, and the Monod kinetic study revealed that the half-saturation constant increased when the BGD concentration crossed the EC50 value. Protein (498 mg/L) and lipid (728 mg/L) accumulation was highest at 5 mg/L of BDG, implying growth-stimulating effects on microalgae as the growth inhibition is less. These findings highlight Scenedesmus obliquus potential for effective BGD removal below EC50 concentrations with identification of 6 biotransformed products and simultaneous production of value-added biomass.
Charcoal Briquette Manufactured from Indonesian Sugar Palm Bunches (Arenga longipes Mogea) as Biomass-Based New Renewable Energy
Hakim L., Iswanto A.H., Lubis Y.S., Wirawan A.J., Batubara R., Kim N.H., Antov P., Rogozinski T., Hua L.S., Chen L.W., Selvasembian R., Jayusman, Sutiawan J.
Article, Journal of Renewable Materials, 2025, DOI Link
View abstract ⏷
The utilisation of sugar palm bunches-charcoal briquettes (SPB-CB) represents a significant advancement in biomass energy. This study aimed to analyse the properties of charcoal briquettes produced from SPB (Arenga longipes). The experiment involved categorising the dimensions of charcoal powder into three specific particle sizes: 20–40 mesh, 40–60 mesh, and particles that could pass through a 60-mesh screen. The charcoal powder will be combined with tapioca as a binding agent at three specific concentrations: 11%, 13%, and 15%. The research findings indicate that the samples underwent 60 mesh passes achieved the maximum briquette density, with an average value of 0.58 g/cm3. The highest attainable compressive strength sample value was 27.52 kgf/cm2, which was attained by employing 60 mesh size and 15% adhesive concentration. The calorimetric investigation showed that SPB-charcoal had the highest calorific value of 25.88 MJ/kg, while the SPB-CB had a little lower caloric value of 24.64 MJ/kg. The ash content and volatile matter values showed that the briquettes with the lowest ash content had values of 10.49% and 32.65%, respectively. Furthermore, the carbon fixation values varied between 16.65% and 52.36%. Thermogravimetric analysis indicates that charcoal derived from SPB exhibits superior thermal characteristics compared to charcoal briquettes. However, thermal properties of SPB charcoal do not show significant differences when compared to charcoal briquettes that have been processed with a mesh size of 20–40 and include 11% adhesive. According to this research, it may be inferred that charcoal briquettes made from sugar palm bunches meet the requirements specified in SNI 01-6235-2000.
An overview on novel CsPbBr3-based perovskite photocatalyst for environmental and energy applications: Synthesis and enhancement strategy
Chauhan R., Sambyal S., Kumar R., Raizada P., Parwaz Khan A.A., Selvasembian R., Ahamad T., Hussain C.M., Singh P.
Review, Journal of Industrial and Engineering Chemistry, 2025, DOI Link
View abstract ⏷
CsPbBr3, an all-inorganic halide perovskite, has garnered attention as a highly promising material for advanced photocatalysis due to its exceptional optoelectronic properties, including photoluminescence quantum yields, high absorption coefficients, and outstanding charge carrier mobility. Notably, compared to organic–inorganic hybrids, CsPbBr3 exhibits enhanced photocatalytic applications. The innovations of this review lie in its comprehensive analysis of recent breakthroughs in heterojunction engineering, especially on the novel S-scheme heterojunction tailored to boost charge separation and redox ability in CsPbBr3 materials. The material's performance has been further strengthened by recent developments in bandgap engineering, surface defects, and heterojunction formation, enhancing photocatalytic applications. In this review, the structural properties, synthesis techniques, and optimization strategies for CsPbBr3 photocatalytic materials are examined. Further, particular attention was paid to doping, surface defects, type-II, Z-scheme, and S-scheme heterojunctions. Also, different photocatalytic applications, like pollutant degradation, H2 evolution, and CO2 reduction, are the main objectives. Emphasis is placed on advanced characterization techniques and performance benchmarks to support the material formation, charge migration, and applications. Finally, the review highlights the challenges and prospects of CsPbBr3-based photocatalysts for environmental applications, aiming to achieve high catalytic efficiency. It offers valuable insights into the use of CsPbBr3-based catalysts in photocatalysis applications.
Biowaste-derived biochars for treatment of wastewater contaminated by dyes
Chizitere Emenike E., Okoro H.K., Iwuozor K.O., Egbemhenghe A.U., Okwu K.C., Adeniyi A.G., Paul S., Akshaya K., Selvasembian R.
Book chapter, Biochar for Environmental Remediation: Principles, Applications, and Prospects, 2025, DOI Link
View abstract ⏷
Biochar is a stable carbon-rich material that is produced by the thermochemical conversion of waste biomass in an oxygen-limited environment. Due to its low production cost, significant surface area, accessibility, thermal stability, high porosity, and the presence of multiple functional groups on its surface, biochar has been used as a promising adsorbent for the treatment of wastewater contaminated by a variety of pollutants. Biochar can be obtained from various sources, including biowaste. Biowaste feedstock refers to organic materials derived from living organisms that can be used as a source of raw material for biochar production. These feedstocks include a diverse range of organic materials derived from biological sources, such as agricultural residues, food waste, livestock manure, and organic municipal solid waste. This chapter provides a concise overview of the use of biochar produced from biowaste for the treatment of wastewater contaminated by dyes. The biochars, which were mostly produced by pyrolysis and hydrothermal carbonization at temperatures between 200°C and 900°C, demonstrated excellent adsorption capacities for the pollutants and correlated well with the Langmuir and Freundlich isotherm models and pseudo-second-order kinetics. The biochars can be further activated and modified to increase their surface area and, subsequently, their adsorption capability. The sorption mechanisms involve both physical and chemical processes. Prospective studies were outlined that will ensure practical applications of biowaste-based biochar.
Integrated formic acid and deep eutectic solvent mediated sustainable synthesis of cellulose nanocrystals from Sterculia foetida shells
Rohil Kumar K., Vishnu N., C.S G., Uppuluri K.B., Selvasembian R.
Article, Preparative Biochemistry and Biotechnology, 2025, DOI Link
View abstract ⏷
The present study reports the green synthesis of cellulose nanocrystals from the shells of Sterculia foetida (SFS) cellulose. Three different methods, alkali, acid and organic acid, were screened for the maximum cellulose extraction. A maximum cellulose yield, 30.6 ± 0.84 w/w, was obtained using 90% formic acid at 110 °C in 120 min. The extracted cellulose was characterized and identified by instrumental analyses. SEM analysis showed skeletal rod-like microfibril structures and similar intra-fibrillar widths. CP/MAS 13C NMR and FTIR spectrum revealed the purity of cellulose and the absence of other components like hemicellulose and lignin. XRD study revealed a cellulose crystallinity index of 88.07%. BET analysis showed a good surface area (3.3213 m2/g) and a micro-pore area of 1.871 m2/g. The cellulose nanocrystals were synthesized from the extracted cellulose using deep eutectic solvents (DES), choline chloride and lactic acid (1:2 ratio). The cellulose nanocrystals (CNC) synthesized from DES-based exhibited zeta potential and particle size of −16.7 mV and 576.3 d.nm. DES-synthesized cellulose nanocrystals were spherical-like shapes, as observed from TEM images. The present results exposed that formic acid is an effective and green catalyst for the extraction of cellulose and DES for the sustainable synthesis of CNC.
Ipoma batatas (sweet potato) leaf and leaf-based biochar as potential adsorbents for procion orange MX-2R removal from aqueous solution
Jabar J.M., Adebayo M.A., Taleat T.A.A., Yilmaz M., Rangabhashiyam S.
Article, Journal of Analytical and Applied Pyrolysis, 2025, DOI Link
View abstract ⏷
The industrial sector of textile effluent discharge comprised majorly of toxic pollutants of synthetic dyes. Lignocellulosic based biomass is a potential precursor for the preparation of biochar type adsorbent for treating wastewater. The present research examined the leaf of Ipoma batatas in the synthesis and application of biochar in the adsorptive removal of procion orange MX-2R (PO) from aqueous solution. The Ipoma batatas biochar (IBB) was prepared from the treatment of Ipoma batatas leaf (IBL) biomass with CaCl2, further activation using microwave-assisted electromagnetic radiation and pyrolysis approach. The batch adsorption assessments of the process parameters were performed with the range of experimental conditions such as initial PO concentration of 1.0–70.0 mg/L, adsorption contact time up to 240 min, solution pH 1.0–11.0, IBL/IBB dosage 0.05–0.30 g/L and adsorption temperature of 303–333 K. The total surface area of IBB exhibited high value of 1175.47 m2/g compared to that of IBL surface area 439.25 m2/g. The equilibrium model analysis showed the adsorption capacity according to Liu model presents 221.20 mg/g (IBL) and 750.80 mg/g (IBB). This study showed the potential of IBB over IBL towards the adsorptive removal of PO from simulated solution.
Biochar for ameliorating soil fertility and microbial diversity: From production to action of the black gold
Ighalo J.O., Ohoro C.R., Ojukwu V.E., Oniye M., Shaikh W.A., Biswas J.K., Seth C.S., Mohan G.B.M., Chandran S.A., Rangabhashiyam S.
Review, iScience, 2025, DOI Link
View abstract ⏷
This article evaluated different production strategies, characteristics, and applications of biochar for ameliorating soil fertility and microbial diversity. The biochar production techniques are evolving, indicating that newer methods (including hydrothermal and retort carbonization) operate with minimum temperatures, yet resulting in high yields with significant improvements in different properties, including heating value, oxygen functionality, and carbon content, compared to the traditional methods. It has been found that the temperature, feedstock type, and moisture content play critical roles in the fabrication process. The alkaline nature of biochar is attributed to surface functional groups and addresses soil acidity issues. The porous structure and oxygen-containing functional groups contribute to soil microbial adhesion, affecting soil health and nutrient availability, improving plant root morphology, photosynthetic pigments, enzyme activities, and growth even under salinity stress conditions. The review underscores the potential of biochar to address diverse agricultural challenges, emphasizing the need for further research and application-specific considerations.
Development and Characterization of Novel Hybrid Particleboard Made from Several Non-Wood Lignocellulosic Materials
Tarigan F.O., Hakim L., Purwoko A., Sucipto T., Nasution H., Fatriasari W., Lubis M.A.R., Sutiawan J., Bakhsi M.I., Kim N.-H., Antov P., Lee S.H., Selvasembian R., Hussin M.H., Aristri M.A., Iswanto A.H.
Article, Polymers, 2025, DOI Link
View abstract ⏷
The green transition trend in the wood-based panel industry aims to reduce environmental impact and waste production, and it is a viable approach to meet the increasing global demand for wood and wood-based materials as roundwood availability decreases, necessitating the development of composite products as alternatives to non-wood lignocellulosic raw materials. As a result, the purpose of this study is to examine and assess the physical, mechanical, and acoustic properties of particleboard manufactured from non-wood lignocellulosic biomass. The core layer was composed of non-wood lignocelluloses (banana stem, rice straw, coconut fiber, sugarcane bagasse, and fibrous vascular bundles (FVB) from snakefruit fronds), whereas the surface was made of belangke bamboo (Gigantochloa pruriens) and wood. The chemical characteristics, fiber dimensions and derivatives, and contact angles of non-wood lignocellulosic materials were investigated. The contact angle, which ranged from 44.57 to 62.37 degrees, was measured to determine the wettability of these materials toward adhesives. Hybrid particleboard (HPb) or sandwich particleboard (SPb) samples of 25 cm × 25 cm with a target density of 0.75 g/cm3 and a thickness of 1 cm were manufactured using 7% isocyanate adhesive (based on raw material oven dry weight). The physical parameters of the particleboard, including density, water content, water absorption (WA), and thickness swelling (TS), ranged from 0.47 to 0.79 g/cm3, 6.57 to 13.78%, 16.46 to 103.51%, and 3.38 to 39.91%, respectively. Furthermore, the mechanical properties of the particleboard, including the modulus of elasticity (MOE), bending strength (MOR), and internal bond strength (IB), varied from 0.39 to 7.34 GPa, 6.52 to 87.79 MPa, and 0.03 to 0.69 MPa, respectively. On the basis of these findings, the use of non-wood lignocellulosic raw materials represents a viable alternative for the production of high-performance particleboard.
Advancements in biomass waste conversion to sustainable biofuels via gasification
Joshua Abioye K., Rajamanickam R., Ogunjinmi T., Paul S., Selvasembian R., Ighalo J.O.
Review, Chemical Engineering Journal, 2025, DOI Link
View abstract ⏷
Biomass gasification is a sustainable technology for syngas production that can help address issues around energy security, waste valorization, and climate change mitigation. This review presents comprehensively the recent advancements in biomass gasification. Elucidates the fundamental principles of biomass gasification and the intricacies of utilizing different gasifying agents and reactor types. Examined the critical process factors and delved into syngas chemistry, highlighting its application in multiple domains. Analysis of the recent advancements in gasification technologies shows that process integration with renewable energy systems, and process control and automation improvements underscore its potential. The review highlighted the need to overcome technical complexities, economic barriers, and regulatory constraints in gasification for widespread adoption to ever be achieved. It was recommended that future research should focus on advanced catalysts, feedstock flexibility, and carbon capture and storage integration.
Pretreatment methods for enhanced biomethane production from crop residues: Progress, challenges, and future perspectives
Krishna Dev K A., Selvasembian R.
Review, Sustainable Energy Technologies and Assessments, 2025, DOI Link
View abstract ⏷
The increase in the global population has caused a rise in the agricultural practice, consequent to increased generation of Crop residues (CR). CR are readily available and less expensive renewable lignocellulosic resource, which is getting more attention in the sector of renewable energy and sustainable development. Pretreatment is an important step in transforming CR into high value chemicals through suitable process. To break down the lignocellulosic CR's resistance and enhance its disintegration into lignin, cellulose, and hemicellulose, a range of pretreatment techniques are used. This review explores the use of advanced pretreatment technologies for CR aimed at improving biomethane production. Discusses the characteristics of CRs, evaluates different pretreatment approaches—physical, chemical, biological, and hybrid methods—and assesses strategies and potential new approaches for integrating waste and energy production. Lignocellulosic wastes, primarily CR stands out the most efficient biomass source for biomethane production because of their abundant availability, high carbon/nitrogen ratio and low ash content. In case of pretreatment methods, hybrid/combined pretreatment emerges as the most promising option when compared to single pretreatment methods, because it offers effectiveness and flexibility in enhancing the biomethane production.
Potential of pyrolyzed and co-pyrolyzed biomass-derived biochar for the removal of ciprofloxacin
Paul S., Selvasembian R.
Review, Journal of Analytical and Applied Pyrolysis, 2025, DOI Link
View abstract ⏷
Second-generation fluoroquinolone antibiotics like ciprofloxacin (CIP) are widely used to treat bacterial infections. Solid landfill leachate, veterinary use, aquaculture, agriculture and hospital wastewater release CIP into the aquatic environment. Herein, the review discusses empirical findings related to the adsorption of CIP in wastewater using biochar, which is considered a low-cost and sustainable adsorbent. An initial ecotoxicological evaluation validated the environmental risk of CIP in the aquatic environment. The review discusses the biochar preparation by the pyrolysis and co-pyrolysis of various biomasses, which were subsequently used as adsorbents for removing CIP from the wastewater. The biochar derived from waste fish scales reported with a high specific surface area of 3370 m2/g. The maximum adsorption capacity for CIP employing biochar was 880.50 mg/g. The mechanisms of CIP adsorption on biochar produced by pyrolysis and co-pyrolysis that are most frequently observed are hydrophobic interactions, hydrogen bonding, pore filling, electrostatic interaction, and π-π electron donor-acceptor interaction. Langmuir and Freundlich models help to explain the CIP adsorption on biochar by providing a better fit for CIP adsorption on biochar, implying that the process involves monolayer and multilayer adsorption. Pseudo-second order kinetics best fit CIP adsorption on biochar, validating chemisorption. Biochar prepared by pyrolysis showed a range of regeneration cycles of 3–10 with good CIP removal efficiency. More research should be emphasized on post-adsorbent disposal, regeneration of co-pyrolyzed biochar, process improvement of the biochar for industrial applications and practical utilization for sustainable waste and water resource management.
Preface
Uppuluri K.B., Selvasembian R.
Editorial, Bioprospecting of Multi-tasking Fungi for Therapeutic Applications: Volume II, 2025,
Bioprospecting of multi-tasking fungi for therapeutic applications: Volume II
Uppuluri K.B., Selvasembian R.
Book, Bioprospecting of Multi-tasking Fungi for Therapeutic Applications: Volume II, 2025, DOI Link
View abstract ⏷
This book covers the multi-tasking nature of fungi for therapeutic applications. It emphasizes the simultaneous metabolic activities and functions of fungi for producing enzyme inhibitors, therapeutic molecules and other biomedical utilities like polymers, nano-composites and biosensors. The fungi are involved in the production of many therapeutically-potent secondary metabolites and polymers. The recent research on fungal bioprospecting is more focused on sustainable solutions for diverse industries and markets for the circular economy. This book also offers current and future research perspectives of fungal bioprospecting. The potential of fungi to act as a bioresource for antimicrobial, antiviral, anticancer, antiprotozoal and antituberculosis compounds has also been discussed. This book is a reference material for undergraduate students for gaining in-depth knowledge on fungal bioprospecting, particularly fungi's multi-tasking nature.
Recent advances in lignin from forest residue for hydrogel application
Bakshi M.I., Nazir S., Restu W.K., Rajamanickam R., Selvasembian R., Hua L.S., Antov P., Yadav K.K., Abbas M., Farobie O., Fatriasari W.
Review, Biomass Conversion and Biorefinery, 2025, DOI Link
View abstract ⏷
Forest waste is a crucial by-product of industries such as sawmills and timber processing facilities. Lignin is extracted from these residues; due to its high abundance, sustainability, inexpensiveness, and good functionality, it is a low-cost, eco-friendly, green, readily available biomass material for hydrogel synthesis. Various techniques, including chemical pulping (alkaline pulping, kraft pulping, soda pulping), acidic pulping (acid sulfite pulping, acidic hydrolysis), organosolv fractionation including microwave-assisted extraction, ionic liquid dissolution, physical processes (steam explosion, homogenization, ultrasonication) and biochemical reactions (enzymatic hydrolysis), are all used to extract lignin from forest residues. The extracted lignin is then processed into a hydrogel through physical and chemical interactions. This review highlights some essential lignin extraction processes, lignin-based hydrogel production techniques, advanced technologies that can be used for hydrogel synthesis (freeze-thawing, stereo complex formation, microwave-assisted synthesis, one-pot synthesis, heat-induced synthesis), and its potential significance of lignin-based hydrogel in different fields such as biomedical and pharmaceutical sectors.
Insights into the potential of Chlorella species in the treatment of hazardous pollutants from industrial effluent
Rajamanickam R., Selvasembian R.
Review, World Journal of Microbiology and Biotechnology, 2025, DOI Link
View abstract ⏷
Effluents from the industrial sector contain a wide range of contaminants in the medium; when they are insufficiently treated and discharged in the aquatic environment, they pollute aquatic matrices, causing deleterious effects on all the lifeforms. Industries such as tanneries, textiles, dairy, pharmaceuticals, paper and pulp, food processing, petrochemicals, iron, and steel generate wastewater containing a wide range of environmentally harmful contaminants. Chlorella species are robust species that can adapt and grow in extreme conditions and have remarkable stress response mechanism with good acclimatization and bioremediation properties. This review aims to provide new insights on the importance of Chlorella in the treatment of industrial effluents. It provides a comprehensive summary of investigations that have proved the potential of Chlorella vulgaris, Chlorella minutissima, Chlorella sorokiniana, Chlorella kessleri, Chlorella ellipsoidea, Chlorella emersonii, Chlorella pyrenoidosa in the elimination of contaminants. Furthermore, highlights the mechanisms that Chlorella undergo in the effluent medium towards the removal of various contaminants.
Critical review on revamping circular economy strategies for the co-production of biosurfactants and lipase from agro-industrial wastes through resource recovery and life cycle assessment
Jaiswal R., Chellam P.V., Selvasembian R.
Article, Biomass and Bioenergy, 2025, DOI Link
View abstract ⏷
In recent decades, biosurfactants have gained a variety of applications in the agro-industrial and environmental sectors. Advances in microbial bioprocessing can address global demand for biosurfactants by intensifying processes on co-production with lipases, enhancing their applications in agro-industrial and environmental sectors. Key challenges in the co-production of lipases and biosurfactants include inefficiencies in resource utilization, recycling, market value retention and environmental impacts. Waste oil cakes from food processing, ayurvedic and petrochemical industries can be used as substrates for lipases and biosurfactants, promoting resource recovery and the circular economy. Though this strategy increases the production rate and the economy associated with this, the key bottlenecks are the stability of the products, understanding the co-metabolism, simultaneous process intensification methods, scaling up, and its end application. This review explores the potential of the circular economy principles, including waste reduction, resource recovery, and resource conservation, to co-produce lipases and biosurfactants. The Life Cycle Assessment (LCA) is discussed in this review to incorporate environmental sustainability in the cumulative production system for lipases and biosurfactants. Adopting a circular economy is beneficial for achieving a balance between economic growth and environmental sustainability in bioprocessing.
Insights into the biodegradation and bioremediation of microplastics: mechanisms and analytical methods
Dogra K., Kumar M., Ornelas-Soto N., Mora A., Sarkar D., Selvasembian R., Deoli Bahukhandi K., Mahlknecht J.
Review, Current Opinion in Chemical Engineering, 2025, DOI Link
View abstract ⏷
Microplastics (MPs) degrade through various abiotic processes (thermal, mechanical, hydrolytic, and photo-oxidative) and biotic processes involving microorganisms. This study investigates specific bacteria, fungi, and algae that contribute to MP biodegradation, focusing on species like Bacillus, Rhodococcus, and Pseudomonas, which produce enzymes such as PETase, laccases, and peroxidases to break down high- and low-density polyethylene. However, the biodegradation process varies based on environmental factors and the durability of plastics. There is an urgent need to use advanced methods to understand degradation and its byproducts. Microbial degradation holds promise for addressing MPs, but further research is needed to enhance efficiency and develop sustainable solutions.
Sustainable approach of modified biochar based adsorbents towards enhanced phosphorus removal from wastewater
Mari Selvam S., Behera B., Chauhan A., Madaan A., Rajamanickam R., Akshaya K., Selvasembian R.
Review, Journal of Analytical and Applied Pyrolysis, 2025, DOI Link
View abstract ⏷
Increasing dependence on non-renewable phosphate rocks has led towards search for new alternative methodologies for recovering it from waste reserves. Natural adsorbents from carbonaceous-rich biochar have gained attention for nutrient recovery and utilization due to their distinctive surface properties and reusability. However, often native biochar lacks appropriate functional groups or porous properties for efficient phosphorus adsorption which emphasizes the need to revisit research field to identify lacunae. Thus, an initial systematic scientometric analysis was conducted to evaluate research gaps, recent advancements, and hot spots associated with biochar-based phosphorus (P) adsorption. Boolean logic model was utilized to retrieve 1694 documents for the period 2011–2023 from web-of-science database. A rapid surge in publications was evident from 2017 onwards. China (61.7 %), USA (15.76 %), South Korea (5.88%), Australia (5.0 %), and India (4.82 %) are the top countries contributing to research domain. Major research hotspots were found to be different activation strategies for performance enhancement, interpretation of complex mechanisms using analytical techniques, and real-time end applications in water and soil. The present review also comprehensively summarizes the effects of biochar production/ modification and adsorption parameters on the P-adsorption efficiency. The underlying mechanisms include ligand/ion exchange, electrostatic interaction, surface precipitation, surface complexation. P-adsorption using biochar mostly follows Langmuir isotherm model suggesting the monolayer chemical process. Assessment of optimization parameters on adsorption process, and underlying environmental and economic impacts of biochar-based adsorbents need to be focussed. Overall, comprehensive summary delineates practicality of scaling-up biochar-based P-adsorption processes to achieve sustainable development goals (SDGs) combined with circular bio-economy perspectives.
Multi-walled carbon nanotubes green-functionalized with iron nanoparticles for continuous removal of pharmaceutical pollutants through fixed-bed adsorption: Integrated experimental and machine learning approaches
Costa H.P.S., Oliveira M.G., Duarte E.D.V., Gomes L., Selvasembian R., da Silva M.G.C., Vieira M.G.A.
Article, Environmental Science and Pollution Research, 2025, DOI Link
View abstract ⏷
Pharmaceutical residues, including losartan and diclofenac, are insufficiently removed by conventional wastewater treatment plants, leading to persistent environmental contamination and potential public health risks. This study addresses this issue by investigating the continuous adsorption of these pharmaceuticals in a fixed-bed column utilizing green-functionalized carbon nanotubes as a sustainable and efficient adsorbent. The adsorbent material was underwent to comprehensive characterization through particle size analysis, zeta potential measurement, CHNS elemental analysis, and X-ray fluorescence, confirming its physicochemical suitability and successful functionalization. Experimental adsorption tests indicated that flow rate significantly influences removal efficiency, with lower flow rates (0.2 mL/min) enhancing retention and extending the mass transfer zone, particularly for losartan. Additionally, higher initial concentrations resulted in earlier breakthrough and saturation, but increased adsorptive capacity. For mass transfer modeling, the modified dose–response (MDR) and dual-site diffusion (DualSD) models provided the best fit to the experimental data. Furthermore, an artificial neural network model demonstrated high predictive accuracy (R2 = 0.9772; MSE = 0.0033), reinforcing the robustness of the system. Among the approaches tested, the DualSD model exhibited the most reliable performance based on parametric statistics (R2adjust and AICc). These findings demonstrate the potential of this green adsorbent for scalable application in the treatment of pharmaceutical-contaminated effluents under continuous flow conditions.
Source profiling, pollution and health risk assessment of heavy metals in agricultural soils around an industrial cluster using PCA and GIS-assisted PMF
Bashir Z., Raj D., Selvasembian R.
Article, Environmental Monitoring and Assessment, 2025, DOI Link
View abstract ⏷
The continuous release of heavy metals (HMs) from nearby industries leads to the contamination of surrounding agricultural areas. This study employed an integrated approach, combining contamination factor (CF), enrichment factor (EF) and geo-accumulation index (Igeo) for pollution assessment, alongside source apportionment using principal component analysis (PCA) and Geographic Information System (GIS)-based positive matrix factorization (PMF), to evaluate HM contamination in agricultural soils of the northeast Guntur district, India. The mean concentrations of HMs, Cu, Cr, Zn, Ni, Cd and Pb exceeded the Indian natural background soil values by 2.59, 1.21, 2.24, 2.09, 1.15 and 1.4 respectively. Pollution indices revealed high contamination for Ni (CF = 2.21) and Cr (CF = 2.05), with Cr showing moderate enrichment (EF ≈ 1.5) and contamination (Igeo = 0.75). PCA identified three components explaining 78.37% of the total variation while GIS-based PMF identified industrial discharges, waste incineration, agriculture and vehicular and industrial emissions as pollution sources. Ni, Cu and Cr were identified as the primary contaminants, with industrial emissions, vehicular traffic and agricultural activities as key contributors to HM pollution. Cr accounted for ~ 80% of the total hazard index, posing significant non-carcinogenic risks for children via ingestion. Carcinogenic risks through ingestion of Ni and Cr were 2.8 and 1.9 times higher than acceptable levels for adults and 3.9 and 2.6 times higher than acceptable levels for children. Additionally, the high bioconcentration factor (BCF) of Lantana viburnoides (Forssk.) with a BCF of 18.29 for Cd suggests a potential environmental hazard. It is imperative to monitor emissions rigorously to safeguard soil quality and optimize industry standards in this region.
Harnessing microalgal consortia potential for the tannery effluent treatment and sustainable valorization of algal biomass
Parveen G.R., Selvasembian R.
Review, Journal of Environmental Chemical Engineering, 2025, DOI Link
View abstract ⏷
The leather industry remains a highly polluting sector among all other industries, as its operations involve extensive chemical use and substantial effluent generation. Tannery effluent can lead to major environmental impacts owing to elevated concentrations of heavy metals, chemical oxygen demand (COD), biochemical oxygen demand (BOD), and other contaminants such as nitrogen, phosphorus, dyes, and sulphur. Heavy metals like chromium, cadmium, zinc, and lead in tannery effluent are highly toxic, which disrupts aquatic life and poses a serious risk to human health through bioaccumulation in the food chain. Microalgal consortia-based biological treatment has emerged as a potential approach of harnessing synergistic interactions for nutrient uptake, heavy metal accumulation, and remediation. Furthermore, microalgae can reduce CO2 levels and reduce phosphate, nitrogen, COD, and BOD from tannery effluent to enhance the wastewater quality. However, challenges persist in scaling microalgal cultivation, optimizing industrial growth conditions, and ensuring economic feasibility. Further research is needed to assess the long-term stability and efficiency of microalgal consortia in varying wastewater compositions. This review critically evaluates the key trends, such as the increasing focus on consortia-based bioremediation over monoculture approaches, along with species-specific potential in pollutant removal and advancements in algal biomass valorization. Various potential consortia of microalgae species such as Chlorella sp., Phormidium sp., Scenedesmus sp., Leptolyngbya sp., Ochromonas sp., Chlamydomonas sp., Diplosphaera sp., and Ganoderma lucidum in providing effective and viable alternatives for tannery effluent treatment have been discussed.
Harnessing nitrogen doped magnetic biochar for efficient antibiotic adsorption and degradation
Rana P., Soni V., Sharma S., Poonia K., Patial S., Singh P., Selvasembian R., Chaudhary V., Hussain C.M., Raizada P.
Review, Journal of Industrial and Engineering Chemistry, 2025, DOI Link
View abstract ⏷
Nitrogen-doped magnetic biochar (N-doped magnetic BC) has garnered significant attention as a multifunctional material for the remediation of antibiotic-contaminated water, owing to its synergistic adsorption and catalytic degradation capabilities. This review critically evaluates the transformative role of pretreatment strategies on the physicochemical attributes of biochar, focusing on nitrogen doping and chemical activation. These methodologies are complemented by post-treatment processes designed to impart synergistically optimized magnetic properties to the biochar matrix. Such modifications are pivotal in fine-tuning the material's characteristics, including surface area, pore architecture, and active site configuration, thereby enhancing its adsorption efficiency and catalytic performance. Advanced characterization techniques, such as electron microscopy, X-ray diffraction, and various spectroscopic modalities, provide comprehensive insights into the structural, surface, and magnetic properties of nitrogen-doped magnetic BC. The adsorption mechanisms are predominantly governed by π-π interactions, hydrogen bonding, and electrostatic forces, with nitrogen doping and magnetic functionalization significantly amplifying the material's selectivity and adsorption capacity. Furthermore, the catalytic degradation of antibiotics occurs via both radical and non-radical pathways, underscoring the dual functionality of the material. Notably, N-doped magnetic BC demonstrates excellent recyclability, maintaining high efficiency across multiple adsorption–desorption cycles. This highlights its potential for sustainable application. Future research directions proposed in this study emphasize advancing the eco-compatibility and scalability of N-doped magnetic BC. Computational modelling is suggested to predict and optimize the material's physicochemical properties, alongside the development of large-scale, environmentally benign synthesis techniques. These advancements aim to position N-doped magnetic BC as a cornerstone material in wastewater treatment systems.
Microalgae and livestock wastewater – A synergistic approach to environmental management
Krishnamoorthy S., Rajamanickam R., Selvasembian R.
Review, Science of the Total Environment, 2025, DOI Link
View abstract ⏷
Livestock wastewater (LW) contains nutrients, pharmaceuticals, heavy metals, and pathogens, significantly contributing to the degradation of water quality. Effective regulation of untreated LW outflows is critical for safeguarding ecosystems and ensuring water security, especially as pollution-induced scarcity intensifies. LW pollution endangers drinking water sources and soil ecology and triggers zoonotic disease risks. Traditional treatment methods often depend on physical and chemical processes that can be expensive, generate carbon emissions, lead to unstable outcomes, and contribute to the waste of recyclable materials, contradicting the principles of sustainable development. Advanced technologies like membrane filtration and oxidation processes, though effective, face economic and operational barriers, particularly for smallholder farmers. Phycoremediation can be effective in treating LW, as it has shown its ability to remove nutrients, heavy metals, and pharmaceuticals from wastewater, and it is feasible to operate in farms with the potential of value-added biomass generation. This review synthesizes recent advancements in microalgae-based LW treatment, focusing on mechanistic pollutant removal pathways, pilot-scale studies, and biomass valorization. It highlights the critical role of microalgae in nutrient recovery, heavy metal and pharmaceutical removal and explores sustainable deployment models, contributing to both environmental protection and bioeconomy growth.
Microalgae-based nutritional supplements: Sustainable applications for high-nutritional-value food production
Rajamanickam R., Das S., T C., Sharma S., R O R., Prabhu A.A., Banerjee S., Azelee N.I.W., Krishnamoorthy S., Selvasembian R.
Review, Process Biochemistry, 2025, DOI Link
View abstract ⏷
Microalgae, photosynthetic organisms that flourish in many aquatic habitats and are rich in vital nutrients, making them a valuable resource for humans and animals, have gained growing interest for their potential to transform into food production. Despite their microscopic size, microalgae are packed with essential nutrients like protein, vitamins, and antioxidants, offering a concentrated source of nutrition. This review aims to explore the nutritional, functional, and commercial potential of microalgae in food applications, focusing on their role in the development of food supplements and novel food formulations. Over recent decades, microalgae have been steadily introduced into the food industry and have seen modest expansion. Due to their high content of beneficial fatty acids (linoleic acid, gamma-linolenic acid, and arachidonic acid), carotenoids, vitamins, phycobilin pigments, highly digestible proteins, lipids, and carbohydrates, microalgae are becoming recognised for their sustainable valorization potential. This review highlights key microalgal species generally recognized as safe (GRAS) and their integration into functional foods. It also discusses emerging trends and biotechnological advancements in microalgae-based food products, underscoring their potential to address global nutritional and sustainability challenges.
Unlocking the potential of marine macroalgae: A comprehensive review of bioactives, extraction techniques, and biorefinery pathways
Farobie O., Azelee N.I.W., Javaid S., Bakhsi M.I., Fatriasari W., Sivaraman S., Selvasembian R.
Review, Process Biochemistry, 2025, DOI Link
View abstract ⏷
Marine macroalgae are versatile third-generation biomass with significant potential to produce high-value bioactive compounds such as pigments, rare sugars, sulfated polysaccharides, and oligosaccharides, which are increasingly relevant for pharmaceutical, nutraceutical, and cosmetic applications. This review hypothesizes that a comprehensive understanding of both well-established and emerging bioactive compounds, along with improvements in extraction methodologies, is essential for realizing the full potential of macroalgae-based biorefineries. Unlike previous studies, this review uniquely consolidates underexplored bioactives and emerging extraction strategies, thereby offering a roadmap for biorefinery development. The contribution of this work lies in identifying critical bottlenecks in macroalgal valorization and presenting integrated biorefinery strategies tailored for sustainable adoption. With the global demand for marine-derived ingredients projected to reach approximately USD 16 billion by 2030, this review highlights commercially viable compounds, eco-efficient extraction routes, and future directions such as the integration of omics technologies, bioprocess intensification, and valorization of underutilized species. The significance of this review lies in highlighting that eco-efficient extraction methods, particularly those using green solvents and process intensification, are the most promising for scalability. Moreover, rare sugars, pigments, and sulfated oligosaccharides remain commercially underexploited yet hold high potential. Addressing biomass variability and economic constraints requires integrated biorefinery strategies. By offering a holistic and forward-looking perspective, this review bridges existing knowledge gaps and provides strategic insights into the future development of sustainable marine macroalgal utilization for high-value industrial applications.
Application of Cellulase From Mutated Aspergillus sp. for the Production of Sustainable 2G Ethanol From Sugarcane Bagasse
Das S., Shakya D., Kaur R., B N.K., T C., Sevda S., Selvasembian R., Prabhu A.A.
Article, Bioenergy Research, 2025, DOI Link
View abstract ⏷
Sugarcane bagasse (SB) is a lucrative feedstock for sustainable fuel production, but economical conversion into fermentable sugars and ethanol presents challenges from a biorefinery perspective. The present study aimed to screen and identify a robust cellulase-producing fungal strain to improve the saccharification of SB. Aspergillus fumigatus exhibited enhanced cellulase activity when untreated SB served as the substrate. The EMS mediated chemical mutagenesis of A. fumigatus with 200 mM EMS further enhanced the cellulase production by approximately 23.47%, relative to the wild-type strain. The process optimization method demonstrated peak cellulase activity on the 6th day of incubation, at 33 °C, and with an inoculum size of 5 × 107 spores. The optimization of the filter paper assay enhanced the maximum activity to 2.5 U/mL by maintaining 6 pH and 55 °C, along with the subsequent addition of MnCl2 ions to the reaction mixture. The Taguchi orthogonal array was employed to optimize the process parameters of enzymatic hydrolysis of alkali-pretreated SB, demonstrating highest efficiency when hydrolysis parameters were set to pH 4, 55 °C, 10 U enzyme, and 20 g/L substrate (SB) loading. The hydrolysate was utilized to evaluate bioethanol production employing Saccharomyces cerevisiae MTCC 824. The strain generated 4.2 g/L of ethanol with a total yield of 0.21 g/g. This study seeks to manage agricultural residues and wastes, generating a nutrient-rich hydrolysate that can be utilized by yeast strains for bioethanol production, thus rendering the entire process sustainable, environmentally friendly, and cost-effective.
Advances on characteristics and valorization of food waste towards the sustainable production of bio-methane and purification
Review, Fuel, 2024, DOI Link
View abstract ⏷
Food waste is primarily generated in marketplaces, agricultural fields, hotels, food manufacturers units, and halls. Food waste have a major impact on food security, quality and safety, economic development, and cause environment pollution. The improper disposal of food waste without proper treatments leads to generation of new diseases, unpleasant odour, air, water, and soil pollution. Nevertheless, food waste is a good substrate which can be disintegrated by digestion process because it exhibits more water contents and biodegradability. The conversion of food waste into biomethane is an appreciable solution in food waste management steps. This manuscript reviews the physico-chemical properties of food waste, various pretreatment methods of food waste to enhance the efficiency of anaerobic digestion (AD) process used to produce biomethane and discussed the impact of operational factors on biomethane production. Subsequently, the need for a biomethane upgradation using physical, chemical, and biological purification approaches was reviewed. In order to improve the efficiency of the anaerobic digestion (AD) process to a large-scale industrial level, the challenges and possible future developments needed to enhance biomethane generation from food waste were also reviewed significantly.
Thermo-Mechanical, Physico-Chemical, Morphological, and Fire Characteristics of Eco-Friendly Particleboard Manufactured with Phosphorylated Lignin Addition
Iswanto A.H., Manurung H., Sohail A., Hua L.S., Antov P., Nawawi D.S., Latifah S., Kayla D.S., Kusumah S.S., Lubis M.A.R., Osvaldova L.M., Hussin M.H., Selvasembian R., Chen L.W., Nurcahyani P.R., Kim N.H., Fatriasari W.
Article, Journal of Renewable Materials, 2024, DOI Link
View abstract ⏷
Lignin, lignosulfonate, and synthesized phosphorylated lignosulfonate were introduced as green fillers in citric acid-sucrose adhesives for bonding particleboard fabricated from areca leaf sheath (ALS). The characteristics of particleboards were compared to that of ultralow emitting formaldehyde (ULEF-UF). The fillers derived from Eucalyptus spp. kraft-lignin were added for flame retardancy enhancement. 10% of each lignin and modified lignin was added into the ULEF-UF and citric acid-sucrose bonded particleboards. Analyses applied to particle-boards included thermal characteristics, X-ray diffraction analysis (XRD), morphological properties, Fourier transform infrared spectroscopy (FTIR), as well as physical, mechanical, and fire resistance characteristics of the laboratory-fabricated particleboards. Lignin and modified lignin resulted in improved thermal stability of the composites bonded with ULEF-UF while the improvement in the particleboard bonded with citric acidsucrose was not significant. The introduction of filler exerted a higher influence on the UF-bonded particleboards compared to composites fabricated with citric acid-sucrose. Generally, the presence of lignin, lignosulfonate, and phosphorylated lignosulfonate enhanced the mechanical strength of the ULEF-bonded particleboards, although their dimensional stability has deteriorated. Markedly, the use of lignin and lignosulfonate enhanced the fire resistance of the particleboards produced with lower observed weight loss. All laboratory particleboards exhibited satisfactory fire resistance, attaining a V-0 rating in according to the UL-94 standard.
Introduction and Characteristics of Biosorbents
Dulta K., Emenike E.C., Iwuozor K.O., Singh D., Singh S., Singh K., Adeniyi A.G., Saranya N., Selvasembian R.
Book chapter, Biosorbents: Diversity, Bioprocessing, and Applications, 2024, DOI Link
View abstract ⏷
Decontamination of toxic pollutants from aqueous solutions is mandatory owing to the deleterious effects they render to the environment. Biosorption is a capable and effective process shown to be more promising than conventional processes like flocculation, sedimentation, coagulation, and filtration. Plant-derived biomasses are natural, eco-friendly nontoxic options utilized in their native form as biosorbents owing to their structural and functional properties suitable for contaminant sequestration. This chapter is brief on the advantages of biosorption and the characteristics of biomass as biosorbents. Also, the parameters to be controlled for maximum adsorption capacity have also been discussed. Characterization procedures for analyzing the biosorbents were also enumerated. This would be useful in understanding the basic knowledge about biosorption and its advantages in removing toxic pollutants from water systems.
Agricultural Biomass/Waste-Derived Adsorbents for the Abatement of Dye Pollutants in (Waste)Water
Haskis P., Ioannidis I., Mpeza P., Giannopoulos G., Barouchas P., Selvasembian R., Pashalidis I., Anastopoulos I.
Book chapter, Planet Earth: Scientific Proposals to Solve Urgent Issues, 2024, DOI Link
View abstract ⏷
Adsorption is an effective and promising technology for removing a variety of pollutants from (waste)water. Many adsorbents are capable of removing pollutants. Among them, clays and clay minerals, nanomaterials, Metal Organic Frameworks (MOFs), Layered Double Hydroxides, Aerogels, Cryogels, Xerogels, etc. Based on the principles of the Circular Economy and Green Chemistry, agri-culture biomass/waste, as renewable, non-toxic, and eco–friendly materials, has attracted the interest to produce adsorbents (raw and/or modified) to decontaminate (waste)water. This chapter contains information about the applicability of pineap-ples, pomegranate-and mango–based adsorbents to remove cationic and anionic dyes. Various adsorption parameters (solution pH, initial concentration, adsorbent dose, temperature, etc.) were explored in detail. Isotherm and kinetic modeling and thermodynamic aspects are also discussed. Maximum adsorption was determined to be 2.98–708.15, 5.42–288.34, and 17.75–1029.11 mg/g for mango, pineapple, and pomegranate-based adsorbents, respectively. The chapter’s conclusions confirm that the investigated materials can successfully remove dye pollutants, and they also suggest a management strategy considering sustainability aspects for dealing with this kind of biomass/waste.
Green Synthesized Bio-nanomaterials for Pollutant Remediation
Aboagye E.A., Santos M.L.S., Dos Santos Lins P.V., Meili L., Franco D.S.P., Georgin J., Selvasembian R.
Book chapter, Nanotechnology for Environmental Management, 2024, DOI Link
View abstract ⏷
In recent years, nanomaterials have come to have strong participation in various areas of society, and with that science and technology have started to invest in this field, providing a strong expansion of nanoscience (Singh et al. 2021, Nayak et al. 2021). Due to the improvement in synthesis and manipulation, new compounds have emerged with diameters and dimensions that are favorable for certain purposes, an example of which is nanoparticles (Auffan et al. 2009, Mercante et al. 2021). Because they have specific characteristics, these materials can be used for different purposes, including wastewater treatment (Patel et al. 2022). Studies have already proven the high efficiency of nanoparticles based on nanofibers and carbon nanotubes in the treatment of several emerging contaminants (Brescia 2022).
Advancements in Microplastic Removal Techniques and Sustainable Solutions for Plastic Reduction
Balasubramaniam D.A., Rajapaksha A.U., Vithanage M., Kumar D., Rajamanickam R., Selvasembian R.
Book chapter, Microplastics: Environmental Pollution and Degradation Process, 2024, DOI Link
View abstract ⏷
The release of microplastics into the ecosystem with wastewater treatment facilities is a growing problem across the world. Wastewater treatment Plants (WWTPs) discharge microplastics in terrestrial and aquatic systems, mostly from the fabric, laundry, and cosmetics sectors. Despite substantial studies on microplastics (MPs) in the natural environment, removal tactics, and WWTP management plans that emphasize their environmental impact, not much is understood concerning MPs’ destiny and behavior during diverse treatment procedures. MPs are affected by treatment methods in varied ways due to their variable physical and chemical properties, resulting in differential removal efficacy. MPs recovered from WWTPs can build in soil and affect ecosystems on land. Few researches have looked at the cost, energy consumption, and alternatives of large-scale microplastic cleanup using contemporary treatment technologies. To protect aquatic and terrestrial environments from microplastic pollution, targeted and cost-effective management strategies must close knowledge gaps. This chapter summarizes recent advances in microplastic removal methods and their efficiencies. Classical treatment method, electrocoagulation method, magnetic extraction, biological process, membrane filtration, pulse clarification, and metal organic frameworks are discussed for microplastic removal. To minimize MPs, alternatives to plastics and severe limitations, such as microplastic waste conversion, should be addressed. MPs should also be managed by policy implementation and awareness.
Effective adsorptive removal of a cationic dye from aqueous solutions using a biosorbent derived from Sargassum sp
da Gama B.M.V., Silanpaa M., Selvasembian R., de Farias Silva C.E., Meili L.
Article, Water Practice and Technology, 2024, DOI Link
View abstract ⏷
The present research evaluated the potential use of the macroalga Sargassum sp., which was modified with filamentous fungus Cunninghamella echinulata for the biosorption of methylene blue (MB) dye. The modified fungal biomass (FERsarg) was obtained through solid-state fermentation of enzyme (alginate lyase). The FERsarg showed a pHPZC of 7.9, a low mass loss, material micro/ mesoporous, and the presence of hydroxyl, carboxylic, phenolic, and carbonyl functional groups. The influence of biomass dosage, solution pH, contact time, initial concentration, and temperature were evaluated for MB biosorption, and the best results were obtained at 2 g L-1 and pH 6. The kinetic study revealed a better fit for the pseudo-second-order model, while the Sips model best described the equilibrium experimental data. The equilibrium was reached within 180 min and showed qmax yielding of 115.49 mg g-1 at 323 K. The thermodynamic understanding of the present research revealed that the biosorbent exhibited spontaneous, exothermic, and physical nature for MB removal. The adsorptive mechanism shows that the process was controlled by electrostatic attraction. Also the feasibility of using residual fermented biomass as a potential adsorbent was applied and discussed, contributing to the concept of minimum waste generation, and supporting the concept of circular bioeconomy.
The Advancements and Detection Methodologies for Microplastic Detection in Environmental Samples
Balasubramaniam D.A., Panneerselvam R., Akshaya K., Rajamanickam R., De-La-torre G.E., Selvasembian R.
Book chapter, Microplastics: Environmental Pollution and Degradation Process, 2024, DOI Link
View abstract ⏷
Microplastics (MPs) contamination has emerged as a significant environmental concern due to its extensive dispersion along with potential adverse effects on aquatic as well as terrestrial ecosystems. Microplastics’ harmful effects have been seen to rise throughout the decades when they mix with other contaminants in a dynamic environmental setting. As a result, developing accurate, effective, and speedy analytical techniques for identifying MPs contamination has become a pressing issue. Understanding the origins, distribution, and implications of MPs requires reliable and efficient detection techniques in environmental samples. This chapter explores the methodologies and strategies for optical detection and identification of MPs in environmental samples, covering their potential, limitations, and the latest advances in destructive (thermal and GC-MS) and non-destructive (Fourier-transform infrared spectroscopy (FTIR) and Raman spectroscopy) detection techniques. By providing a brief overview of these detection methods, this chapter aims to inform further analysis and research efforts, evaluating their applicability across various sample matrices.
Microplastics: Environmental Pollution and Degradation Process
Mishra A.K., Raizada P., Helmy E.T., Arockiasamy S., Selvasembian R.
Book, Microplastics: Environmental Pollution and Degradation Process, 2024, DOI Link
View abstract ⏷
This book presents microplastics pollution in land and water bodies, their hazardous effects, characterization approaches, and suitable means of utilizing advanced treatment options to solve the problem. It is mainly understood that microplastic pollutants are associated with water bodies, however there also exists soil contamination and their interaction with the food web. The discussions related to strategies and policies for the management of microplastics are very limited. This book not only narrows microplastic pollution in marine or fresh water bodies, but also takes into account the terrestrial environment, including the toxicity effects, characterization aspects and treatment approaches. The main feature of the book includes latest research related to microplastics pollution, examining the different health effects including environmental (related) issues and highlights the advances in treatment approaches. The book serves as a guide with an up-to-date information on microplastics related problems, useful for students, researchers, professionals/environmentalists and also as a reference for policy makers.
Biochar as a Catalyst in Biorefineries: A Sustainable Recovery of Waste Materials
Venkatachalam P., Sriariyanun M., Shanmugam S.R., Selvasembian R.
Editorial, Applied Science and Engineering Progress, 2024, DOI Link
Emerging Trends in Microbial Electrochemical Technologies for Sustainable Mitigation of Water Resources Contamination: Microbial Electrochemical Technologies in Wastewater Treatment
Selvasembian R., Mal J., Das S., Verma D.K., Anastopoulos I.
Book, Emerging Trends in Microbial Electrochemical Technologies for Sustainable Mitigation of Water Resources Contamination: Microbial Electrochemical Technologies in Wastewater Treatment, 2024, DOI Link
View abstract ⏷
The book aims to highlight the application of microbial electrochemical technologies, their fundamental to advanced, recent applications, management strategies, and relevant case studies. The book also attempts to highlight existing research and technological advancements on all facets of instruments and methods for assessing and keeping track of water contaminants. The section on current trends and advancements in this book discusses the most recent advancements in microbial electrochemical technologies and related technologies to lessen the contamination of water resources. The book goes into great detail about the fundamental aspects of water pollution, including their causes, primary sources, detection, treatment, and mitigation using microbial electrochemical technologies and management systems as well as commercialization and economics thoughts that are currently of significant importance. Additionally, with the aid of appropriate tables and figures, all of these chapters havebeen arranged according to recent developments and aspects of the field. The book's goal is to give readers a fundamental understanding of how microbial electrochemical technologies work. It is intended for a wide range of readers, including undergraduate and graduate students, researchers, academicians, environmentalists, policymakers, businesspeople, and R&D teams. We gratefully thank all of the authors. We'll be open to recommendations for making the next book or edition better.
Plant biomass materials in water treatment applications
Saranya N., Ramprasad C., Selvasembian R.
Book chapter, Plant Biomass Applications: Materials, Modification and Characterization, 2024, DOI Link
View abstract ⏷
Water matrices are deteriorating owing to the tremendous accumulation of pollutants from domestic and industrial wastes. Adsorption is a simple and promising technology, where plant biomass and agrowastes are utilized as biosorbents in alleviating toxic pollutants from wastewater. This chapter enumerates various pollutants that predominantly persist in the water bodies and their toxicity. Various plant biomasses in raw form, chemically and thermally activated forms, and their efficacy in removing water pollutants have been detailed. Lignocellulosic plant biomass has diverse surface functional groups, whereas activated biochars exhibit several advantageous properties, including high surface area and porosity, which are suitable for pollutant binding and decontamination. Being cost-effective and biodegradable, plant-based biosorbents are better alternatives for conventional pollutant treatment methods from water bodies.
Application of Microalgae-MFC to MitigateWater Pollution and Resource Recovery
Rajamanickam R., Selvasembian R.
Book chapter, Emerging Trends in Microbial Electrochemical Technologies for Sustainable Mitigation of Water Resources Contamination: Microbial Electrochemical Technologies in Wastewater Treatment, 2024, DOI Link
View abstract ⏷
Microbial fuel cells (MFCs) are simple bio-electrochemical devices that have the potential to treat wastewater and generate power through anaerobic respiration of microorganisms. Microalgae can grow in wastewater conditions utilizing CO2, nutrients, and other pollutants from the medium, and it has good symbiotic interactions with bacteria; this synergetic interaction has gained its application in integrating with microalgae-based MFCs. Microalgae produce O2 through photosynthesis, can reduce the need for external oxygen supply, and can take part in the cathodic process. The bacteria from the anodic compartment capture O2 and provide bioelectricity. Microalgae-integrated MFC can treat wastewater and provide sustainable bioenergy conversion through biomass production. This approach has led to the application of MFCs with algae-assisted cathodes to treat wastewater and generate power. The harvested biomass from this integrated treatment system can produce value-added products through biorefinery approaches. This chapter aims to cover the advantages associated with micro-algaeintegrated MFC for the application of electricity generation, carbon capture, wastewater treatment, algal biomass production, operating conditions, and its impacts on power generation.
Enhancing Methylene Blue Dye Removal using pyrolyzed Mytella falcata Shells: Characterization, Kinetics, Isotherm, and Regeneration through Photolysis and Peroxidation
de Lima R.S., Tonholo J., Rangabhashiyam S., Fernandes D.P., Georgin J., de Paiva e Silva Zanta C.L., Meili L.
Article, Environmental Management, 2024, DOI Link
View abstract ⏷
The potential of pyrolyzed Mytella falcata shells as an adsorbent for removing methylene blue dye molecules from aqueous solutions was investigated. The study found that the adsorbent produced at 600 °C of pyrolysis temperature, with an adsorbent mass of 0.5 g, particle diameter of 0.297–0.149 mm, and pH 12.0, demonstrated the highest dye molecule removal efficiency of 82.41%. The material’s porosity was observed through scanning electron microscopy, which is favorable for adsorption, while Fourier-transform infrared spectroscopy and X-Ray diffraction analysis analyses confirmed the presence of calcium carbonate in the crystalline phases. The pseudo-second order model was found to be the best fit for the data, suggesting that the adsorption mechanism involves two steps: external diffusion and diffusion via the solid pores. The Redlich-Peterson isotherm model better represented the equilibrium data, and the methylene blue adsorption was found to be spontaneous, favorable, and endothermic. The hydrogen peroxide with UV oxidation was found to be the most efficient method of regeneration, with a regeneration percentage of 63% achieved using 600 mmol.L−1 of oxidizing agents. The results suggest that pyrolyzed Mytella falcata shells could serve as an ecologically viable adsorbent alternative, reducing the amount of waste produced in the local environment and at the same time removing pollutants from the water. The material’s adsorption capacity remained almost constant in the first adsorption-oxidation cycles, indicating its potential for repeated use.
Optimized Hydrothermal Synthesis of Chitosan-Epichlorohydrin/Nanosilica for Efficient Reactive Dye Removal: Mechanistic Insights
Wu R., Abdulhameed A.S., Selvasembian R., Yousif E., ALOthman Z.A., Jawad A.H.
Article, Water, Air, and Soil Pollution, 2024, DOI Link
View abstract ⏷
In this study, a cross-linked chitosan-epichlorohydrin/nanosilica (CS-EPH/NSi) bionanocomposite was prepared using a simple two-step process. First, functionalization of chitosan with nanosilica followed by crosslinking process with epichlorohydrin. The CS-EPH/NSi bionanocomposite’s adsorption property toward the removal of reactive orange 16 (RO16) dye was evaluated. The adsorption process of RO16 by CS-EPH/NSi was optimized using Box-Behnken design (BBD). The desirability function results revealed that the highest removal of RO16 (96.32%) is achieved at the following experimental conditions: solution pH of 4.26, dosage of CS-EPH/NSi = 0.089 g/100 mL, and contact time of 9.69 min. The Langmuir isotherm model was found to describe the equilibrium behavior of the monolayer adsorption process at 25 °C. The kinetics data of RO16 adsorption by CS-EPH/NSi were appropriately described by a pseudo-second order model, which suggests that the adsorption process occurs via chemisorption. The high adsorption capacity of CS-EPH/NSi for RO16 (110.2 mg/g) can be attributed to the electrostatic forces between the positively charged CS-EPH/NSi and the negatively charged RO16 anions, as well as n-π and H-bond interactions. Overall, this study demonstrates the potential of CS-EPH/NSi as an adsorbent for the efficient removal of textile RO16 dye.
Sustainability, performance, and production perspectives of waste-derived functional carbon nanomaterials towards a sustainable environment: A review
Poonia K., Singh P., Ahamad T., Le Q.V., Phan Quang H.H., Thakur S., Mishra A.K., Selvasembian R., Hussain C.M., Nguyen V.-H., Raizada P.
Article, Chemosphere, 2024, DOI Link
View abstract ⏷
The survival of humanity is severely threatened by the massive accumulation of waste in the ecosystem. One plausible solution for the management and upcycling of waste is conversing waste at the molecular level and deriving carbon-based nanomaterial. The field of carbon nanomaterials with distinctive properties, such as exceptionally large surface areas, good thermal and chemical stability, and improved propagation of charge carriers, remains a significant area of research. The study demonstrates recent developments in high-value carbon-based photocatalysts synthesis from various waste precursors, including zoonotic, phytogenic, polyolefinic, electronic, and biomedical, highlighting the progression as photocatalysts and adsorbents for wastewater treatment and water splitting applications. This review highpoints the benefits of using waste as a precursor to support sustainability and circular economy and the risks associated with their use. Finally, we support that a sustainable society will eventually be realized by exploring present obstacles and potential steps for creating superior carbon-based nanomaterials in the future.
“Long COVID” and Its Impact on The Environment: Emerging Concerns and Perspectives
Rana P., Patial S., Soni V., Singh P., Khosla A., Thakur S., Hussaisn C.M., de Carvalho Nagliate P., Meili L., Selvasembian R., Raizada P.
Article, Environmental Management, 2024, DOI Link
View abstract ⏷
The COVID-19 pandemic has caused unprecedented global health and economic crises. The emergence of long COVID-19 has raised concerns about the interplay between SARS-CoV-2 infections, climate change, and the environment. In this context, a concise analysis of the potential long-term effects of the COVID-19 epidemic along with the awareness aboutenvironmental issues are realized. While COVID-19 effects in the short-term have reduced environmental air pollutants and pressures, CO2 emissions are projected to increase as the economy recovers and growth rates return to pre-COVID-19 levels. This review discusses the systematic effects of both the short-term and long-term effects of the pandemic on the clean energy revolution and environmental issues. This article also discusses opportunities to achieve long-term environmental benefits and emphasizes the importance of future policies in promoting global environmental sustainability. Future directions for growth and recovery are presented to cope with long COVID-19 epidemic along with the critical findings focussing on various aspects: waste management, air quality improvement. (Figure presented.)
Mixed food waste valorization using a thermostable glucoamylase enzyme produced by a newly isolated filamentous fungus: A sustainable biorefinery approach
Das S., T C., Selvasembian R., Prabhu A.A.
Article, Chemosphere, 2024, DOI Link
View abstract ⏷
Food waste is a lucrative source of complex nutrients, which can be transformed into a multitude of bioproducts by the aid of microbial cell factories. The current study emphasizes isolating Glucoamylase enzyme (GA) producing strains that can effectively break down mixed food waste (MW), which serves as a substrate for biomanufacturing. The screening procedure relied heavily on the growth of isolated fungi on starch agar media, to specifically identify the microbes with the highest starch hydrolysis potential. A strain displayed the highest GA activity of 2.9 ± 0.14 U/ml which was selected and identified as Aspergillus fumigatus via molecular methods of identification. Exposure of the A. fumigatus with 200 mM Ethyl methanesulphonate (EMS) led to a 23.79% increase compared to the wild-type GA. The growth conditions like cultivation temperature or the number of spores in the inoculum were investigated. Further, maximum GA activity was exhibited at pH 5, 55 °C, and at 5 mM Ca2+ concentration. The GA showed thermostability, retaining activity even after long periods of exposure to temperatures as high as 95 °C. The improvement of hydrolysis of MW was achieved by Taguchi design where a maximum yield of 0.57 g g−1 glucose was obtained in the hydrolysate. This study puts forth the possibility that mixed food waste, despite containing spices and other microbial growth-inhibitory substances, can be efficiently hydrolyzed to release glucose units, by robust fungal cell factories. The glucose released can then be utilized as a carbon source for the production of value-added products.
Adsorption study of isotherms, kinetics modelling, and thermodynamics of immobilized Candida rugosa lipase on metal oxide for esterification of waste cooking oil
Ramlee N.N., Illias R.M., Toemen S., Rahman R.A., Selvasembian R., Fatriasari W., Azelee N.I.W.
Article, Chemical Engineering Research and Design, 2024, DOI Link
View abstract ⏷
The problem regarding improper disposal of waste cooking oil (WCO) can be solved via biotransformation of WCO to value added product using lipases as a biocatalyst. Thus, immobilization method was proposed for the recyclability of the biocatalyst. However, a comprehensive discussion on adsorption study is limited for lipase immobilization. In this study, Candida rugosa lipase (CRL) was immobilized on modified metal oxide (Mg2+/Al2O3) and the support was improved by addition of activating agent (L-lysine/Mg2+/Al2O3). Subsequently, the biocatalysts were used for esterification of WCO in the presence of methanol. Maximum adsorption capacity for the support was improved after addition of L-lysine resulting in 0.262 mg protein/g of support. The equilibrium adsorption data for both systems were fitted to the Redlich Peterson isotherm model while the kinetics study was most fitted with Elovich model, and the adsorption process were influenced by intraparticle and film diffusion mechanisms. Thermodynamic analysis explained that the adsorption process of CRL/L-lysine/Mg2+/Al2O3 was more spontaneous and stronger as compared to CRL/Mg2+/Al2O3. Furthermore, CRL/L-Lysine/Mg2+/Al2O3 exhibited its potential in esterification of WCO by converting 62.95% of free fatty acid (FFA), while CRL/Mg2+/Al2O3 converted lower FFA (53.62%). This study offers a fundamental understanding on designing an effective immobilization system by addition of activating agent to develop a good biocatalyst for biotransformation of WCO.
Towards sustainable approach of the waste tyres employment in water pollutant sequestrations
Srinivasan S., Rajapaksha A.U., Ashiq A., Magalhaes Oliveira L.M.T.D., Lins P.V.S., Meili L., Selvasembian R.
Review, Journal of Cleaner Production, 2024, DOI Link
View abstract ⏷
Worldwide population growth has considerably increased the use of automobiles, which has raised serious concerns about the production of vast quantities of waste tyres (WT) and subsequent disposal problems. When WT builds up in the environment without proper recycling strategies, toxic repercussions in various forms increase. The practice of clearing waste through open air burning has been abandoned, and it poses major risks to human health and atmospheric pollution. Reuse of WT is accomplished via several recycling techniques. The WT pyrolysis approach is discussed in this review, which is described as a thermochemical process carried out at high temperature to convert WT mainly into charcoal, a material used as an adsorbent agent. In addition to this solid portion, pyrolysis produces liquid and gas fractions, all influenced by the conditions of the pyrolysis process. This review provides a cutting-edge critical appraisal of studies on adsorbents made from char generated during pyrolysis and its use in the sequestration of pollutants from wastewater. In summary, this review on the WT pyrolysis focuses a promising approach to addressing disposal challenges, lowering harmful environmental impacts, and proposing an effective solution for removing pollutants from water.
Preface The 5th TALENTA Conference on Engineering, Science and Technology (TALENTA CEST) 2024
Ambarita H., Selvasembian R., Fachrudin H.T., Huda A.
Editorial, E3S Web of Conferences, 2024, DOI Link
Pyrolyzed coal base high surface area and mesoporous activated carbon for methyl violet 2B dye removal: Optimization of preparation conditions and adsorption key parameters
Musa S.A., Abdulhameed A.S., Baharin S.N.A., ALOthman Z.A., Selvasembian R., Jawad A.H.
Article, Chemical Engineering Research and Design, 2024, DOI Link
View abstract ⏷
Herein, a low-grade Malaysian coal namely Merit Karpit coal (MRTKC) was transformed into high surface area mesoporous activated carbon (MRTKC-AC) via pyrolysis-assisted ZnCl2 activation. A numerical optimization approach rooted in the Box-Behnken design (BBD) was employed to determine the best operational conditions such as A: dosage of MRTKC-AC (ranging from 0.02 to 0.1 g/100 mL), B: the pH of the solution (varying from 4 to 10), and C: the contact time (ranging from 5 to 25 min). A notable surface area of 1229.1 m2/g and a distinctive mesoporous structure with an average pore diameter of 2.9 nm was achieved at optimum impregnation ratio (1 MRTKC: 2 ZnCl2), heating temperature 500 °C, and residence time 60 min. Moreover, the application of MRTKC-AC was evaluated through the removal of methyl violet (MV) from the aqueous environment. The comprehensive equilibrium and kinetic adsorption analyses showed that the adsorption of MV by MRTKC-AC matched closely to the Langmuir isotherm model, while the kinetic behavior was suitably described by the pseudo-second order model. Thus, the maximum adsorption capacity (qmax) for MV dye onto MRTKC-AC was ascertained to be a substantial 238.6 mg/g. The MV dye adsorption mechanism onto MRTKC-AC surface indicates various dye–adsorbent interactions: electrostatic attraction, p–p interaction, and H-bonding. This work shows that Malaysian low-rank coal is an economical precursor for producing low-cost and efficient mesoporous activated carbon with substantive surface area.
Ni-based plasmonic photocatalysts for solar to energy conversion: A review
Poonia K., Nguyen T.T.H., Singh P., Ahamad T., Thakur S., Nguyen V.-H., Kim S.Y., Le Q.V., Chaudhary V., Khan A.A.P., Selvasembian R., Mishra A.K., Gautam S., Raizada P.
Article, Molecular Catalysis, 2024, DOI Link
View abstract ⏷
Plasmonic-based semiconductors are compelling contenders of current research endeavors to drive chemical reactions via plasmonic and phononic light-matter interactions. Among various plasmonic metals, Ni as a non-precious metal has been extensively studied due to its ability to participate in interband excitation and comparable metal-hydrogen binding energy to that of noble metals including Pt and Ag. The phenomenally high charge-carrier density in photoexcited Ni-based plasmonic nanomaterials offers photochemical conversion of high-energy chemical bonds accompanied by thermal effect. Since the research on the plasmonic activity of the non-precious metal is still emerging, no comprehensive review has addressed the significance of Ni as a plasmonic photocatalyst to the best of our knowledge. This review article sums up the recent progress in the field of plasmonic photocatalysis focusing on Ni-based photocatalysts. The basic principles of the plasmonic effect have been presented, along with an explanation of why Ni may be a viable option. Ni has been investigated for use as a co-catalyst and plasmonic photocatalyst in composite photocatalysis to achieve an accelerated process. After the energy transfer mechanism has been assessed, the review covers the state-of-the-art of two significant effects—plasmon energy transfer and the localized heating effect that are responsible for increased efficiency in energy production. In conclusion, we have included a synopsis of the assessment and emphasized the problems that must be resolved before the technology can be made available for purchase. In a nutshell, the chemistry of plasmonic photocatalysis is promising; but acquiring a detailed mechanism of charge transfer and utilization of charge carriers is still a roadblock in apprehending the full potential of plasmonic photocatalysis. Therefore, this study aims to motivate the scientific community to envision impactful work in the creation of next-generation plasmonic photocatalysts.
Insects to the rescue? Insights into applications, mechanisms, and prospects of insect-driven remediation of organic contaminants
Gwenzi W., Gufe C., Alufasi R., Makuvara Z., Marumure J., Shanmugam S.R., Selvasembian R., Halabowski D.
Review, Science of the Total Environment, 2024, DOI Link
View abstract ⏷
Traditional and emerging contaminants pose significant human and environmental health risks. Conventional physical, chemical, and bioremediation techniques have been extensively studied for contaminant remediation. However, entomo- or insect-driven remediation has received limited research and public attention. Entomo-remediation refers to the use of insects, their associated gut microbiota, and enzymes to remove or mitigate organic contaminants. This novel approach shows potential as an eco-friendly method for mitigating contaminated media. However, a comprehensive review of the status, applications, and challenges of entomo-remediation is lacking. This paper addresses this research gap by examining and discussing the evidence on entomo-remediation of various legacy and emerging organic contaminants. The results demonstrate the successful application of entomo-remediation to remove legacy organic contaminants such as persistent organic pollutants. Moreover, entomo-remediation shows promise in removing various groups of emerging contaminants, including microplastics, persistent and emerging organic micropollutants (e.g., antibiotics, pesticides), and nanomaterials. Entomo-remediation involves several insect-mediated processes, including bio-uptake, biotransfer, bioaccumulation, and biotransformation of contaminants. The mechanisms underlying the biotransformation of contaminants are complex and rely on the insect gut microbiota and associated enzymes. Notably, while insects facilitate the remediation of contaminants, they may also be exposed to the ecotoxicological effects of these substances, which is often overlooked in research. As an emerging field of research, entomo-remediation has several knowledge gaps. Therefore, this review proposes ten key research questions to guide future perspectives and advance the field. These questions address areas such as process optimization, assessment of ecotoxicological effects on insects, and evaluation of potential human exposure and health risks.
Critical review on the tetracycline degradation using photo-Fenton assisted g-C3N4-based photocatalysts: Modification strategies, reaction parameters, and degradation pathway
Sharma S., Sudhaik A., Sonu, Raizada P., Ahamad T., Thakur S., Van Le Q., Selvasembian R., Nguyen V.-H., Mishra A.K., Singh P.
Article, Journal of Environmental Chemical Engineering, 2024, DOI Link
View abstract ⏷
Over the years, the enormous use of tetracycline (TC) in pharmaceutical industries caused unwanted heap in the environment that led to the deterioration of human and ecological conditions. Therefore, the synergistic functioning of photo-Fenton and photocatalysis has been introduced which enables the regeneration of more •OH, •O2- species thereby enhancing the TC degradation performance of photocatalysts. Graphitic carbon nitride (g-C3N4) photocatalyst recently, gained massive consideration due to the suitable energy band gap, efficient preparation method, and physicochemical properties. However, due to some drawbacks, various modification strategies (doping, Z-Scheme, S-Scheme) have been adopted to perk up the degradation activity of bare g-C3N4. In the current review, we have provided insights into various modification strategies employed for g-C3N4 and reaction parameters for the effective remediation of tetracycline using photo-Fenton-assisted photocatalysis. The review further highlighted the potential of the integrated effect of g-C3N4-based photo-Fenton-assisted photocatalytic processes for achieving higher tetracycline removal efficiency followed by current challenges and future perspectives.
A sustainable resource recovery approach through micro-algae integrated brine management in minimal liquid discharge system
Rajamanickam R., Selvasembian R.
Review, Desalination, 2024, DOI Link
View abstract ⏷
Nutrients, heavy metals, micropollutants, and organic contaminants are all present in the minimal liquid discharge (MLD) discharge water as the MLD is designed to recover 95 % of the water from the wastewater, and the remaining 5 % is disposed of through conventional or advanced disposal strategies. The rejected brine cannot be utilized or discarded without eliminating the impurities. Microalgae cultivation in brine medium has been extensively researched for potential in the utilization of nutrients in the medium for its growth, and the harvested biomass can be beneficial and can become one of the efficient brine management strategies. The microalgae technique is considered sustainable and ecologically friendly compared to other brine management strategies because it generates zero secondary pollutants and provides income through biomass valorization. This review investigates the characteristics of brine from various MLD sectors; Tolerance of microalgae species in brine medium; Microalgae bioremediation and the mechanism adapted for the removal of nutrients, pollutants and other contaminants from the brine; Case studies that implemented microalgae-based brine management; and sloping microalgae solar evaporation pond system. Most significantly, the waste can be recovered as value-added bioproducts for the various sectors fulfilling the Sustainable Development Goals through microalgae brine management.
Correction to: Hexavalent chromium adsorption onto environmentally friendly mesquite gum-based polyurethane foam (Biomass Conversion and Biorefinery, (2024), 14, 13, (15021-15036), 10.1007/s13399-022-03528-4)
Sasidharan V., Georgin J., Franco D.S.P., Meili L., Singh P., Jawad A.H., Selvasembian R.
Erratum, Biomass Conversion and Biorefinery, 2024, DOI Link
View abstract ⏷
The authors regret the mistake due to the omission of two references works carried out by Acuña et al. [1] and Ranote et al. [2]. 2.2. Preparation of adsorbents Crude Mesquite gum was purified based on the reported procedure by Acuña et al. [1] and Ranote et al. [2]. The samples of gum were subjected to drying at 80°C for 120 min and powdered through mortar and pestle. The obtained powdered gum was used further by dissolving 10.0 g in 250 mL of deionized water along with 10% of acetone. The mixture is allowed for mixing using a stirrer and results in the precipitation of pure gum. The obtained pure gum was a second time treated with 100 mL acetone. Finally, the pure gum obtained as precipitates was washed and dried. The resultant 5 g of purified gum acts as the source of bio-polyol, which was transferred into 5 mL of deionized water followed by 0.05 g DABCO, 0.06 g silicone oil, and 0.1 g Sargassum under the condition of constant stirring. The content was treated with the gradual addition of 1.5 g MDI associated with high stirring. These follow the foam formation with rapid solidification in the form of MG-PUF and Sa-MG-PUF, which were washed using deionized water and oven-dried at 60°C for 24 h, and used as adsorbents. These adsorbent performances were compared with commercial polyurethane form (CPF) adsorbents. The authors would like to apologize for any inconvenience caused. The original article has been corrected.
Hexavalent chromium adsorption onto environmentally friendly mesquite gum-based polyurethane foam
Sasidharan V., Georgin J., Franco D.S.P., Meili L., Singh P., Jawad A.H., Selvasembian R.
Article, Biomass Conversion and Biorefinery, 2024, DOI Link
View abstract ⏷
This study aimed to produce an eco-friendly bio-based polyurethane foam with mesquite gum (MG) and Sargassum sp. biomass (SA) to remove hexavalent chromium from an aqueous solution by adsorption. The synthesized PU foam presented a smooth and regular surface compared to the commercial polyurethane foam (CPF), the mesquite gum and sargassum presented new irregularities and voids distributed randomly. The synthesis provided a chemical change, confirmed by FT-IR, where new bands were evidenced. Last, it was found that the modification conducted generated new crystalline peaks, characterized by organized structures and uniform arrangements. For all materials, equilibrium was reached before 120 min, confirming a fast kinetic time. The general order model was the most suitable model to fit the kinetic data. The maximum experimental adsorption capacity of Cr(VI) was 222 mg g−1, at 303 K and pH 2.0, for the composite, which has great potential to be used as a low-cost adsorbent for Cr(VI) removal from water.
Upcycling of polyethylene terephthalate (PET) plastic wastes into carbon-based nanomaterials: Current status and future perspectives
Soni V., Dinh D.A., Poonia K., Kumar R., Singh P., Ponnusamy V.K., Selvasembian R., Singh A., Chaudhary V., Thakur S., Nguyen L.H., Phan Thi L.-A., Nguyen V.-H., Raizada P.
Review, European Polymer Journal, 2024, DOI Link
View abstract ⏷
To date, the prevalence of commonly used plastics like Polyethylene terephthalate (PET), polylactic acid (PLA), and polybutylene terephthalate (PBT) extends across diverse industries, from textiles to beverage bottles and daily packaging applications. Originally designed for up to 50 years of durable shelf life, these plastics face accelerated disposal challenges due to the pervasive “throw-away” culture. The rapid expansion of single-use plastic manufacturing, notably PET, has led to an astonishing global output of one million tons of plastic each year, highlighting the urgent requirement for efficient solutions in managing plastic waste. Carbon-based nanomaterials derived from PET are synthesized using chemical reactions in solution or high-temperature environments. This review discusses molten salt, hydrothermal, and one-step solvent-based synthesis techniques. We investigate advances in converting PET plastic into nanostructured materials, revealing their potential for energy storage, adsorption, supercapacitors, and sensors. As we navigate the challenges of plastic waste, this review scrutinizes the environmental impact by bridging the gap between plastic pollution and the utilization of upcycled nanomaterials of these pioneering methods, offering insights into their sustainability.
Recent advances in synthesis methods and surface structure manipulating strategies of copper selenide (CuSe) nanoparticles for photocatalytic environmental and energy applications
Chawla A., Sudhaik A., Sonu, Kumar R., Raizada P., Khan A.A.P., Ahamad T., Nguyen V.-H., Selvasembian R., Kaushik A., Singh P.
Review, Journal of Environmental Chemical Engineering, 2024, DOI Link
View abstract ⏷
The design and development of green and chemical nanomaterials is crucial because these systems can possess desired and manipulative photocatalysis and electrocatalysis. To achieve these features at the same time, Klockmannite Copper selenide (CuSe) emerging as a potential p-type semiconductor exhibits shape and size-dependent functional, optical, and electrical properties. Additionally, alterable bandgap, metallic character, localized surface plasmon resonance, and significant light absorption variability of CuSe make this class of material an efficient technological material. To cover the gaps in the field of CuSe and explore the potential to manage a sustainable environment, this review provides an overview of the design and development of green and chemical (but acceptable) CuSe for various advanced applications due to its indirect bandgap of 0.15–2.7 eV and scaled up synthesis using both top-down and bottom-up approaches. Despite numerous advantages, the limitations related to CuSe such as a small bandgap, charge carrier recombination, and a restricted ability to absorb visible light are also discussed in this article. Further, various modification possibilities, including doping or creating heterojunctions utilizing traditional (Type-I, -II, -III) and conventional techniques (Z-, Dual-Z-, S-scheme, etc.) to overcome these restrictions are also discussed carefully and critically. Functions of CuSe in energy conversion, supercapacitors, sensors, and environmental issue solutions have been covered in this study. Future outlooks, viewpoints, and conclusions on the subject have all been presented. We believe that this article will serve as a key document to project and promote CuSe for next-generation photocatalysis.
Potential and Opportunities of Waste Biomass Valorization Toward Sustainable Biomethane Production
Akshaya K., Selvasembian R.
Review, ChemBioEng Reviews, 2024, DOI Link
View abstract ⏷
The increasing global population has led to a surge in waste production across various fields including agriculture, industry, marine, and household, posing significant waste management challenges. Concurrently, the world is facing an energy crisis, emphasizing the crucial need for sustainable and renewable energy sources. This comprehensive review examines the potential of biomethane production from diverse waste biomass. Feedstock characteristics; anaerobic digestion (AD); biochemical pathways; factors influencing AD; various pretreatment methods such as physical, chemical, biological, and combined; existing policies supporting biomethane production; and potential new policy implications are discussed in this review along with the significance of waste-to-energy integration. Our findings indicate that lignocellulosic wastes, primarily agricultural waste, stand out as the most efficient biomass source for biomethane production due to their characteristics such as high carbon/nitrogen ratio, low ash content, and their abundant availability. Among pretreatment methods, combined pretreatment emerges as the most promising option, offering flexibility and effectiveness in enhancing biomethane production. Additionally, the two-stage digester configuration proves advantageous in overcoming limitations associated with single-stage digesters such as pH inhibition. Altogether, the review highlights that biomethane production from waste biomass through AD offers a sustainable solution.
Preface
Uppuluri K.B., Selvasembian R.
Editorial, Bioprospecting of Multi-tasking Fungi for a Sustainable Environment: Volume I, 2024,
Recent advances in superhydrophobic paper derived from nonwood fibers
Fatriasari W., Daulay I.R.S., Fitria, Syahidah, Rajamanickam R., Selvasembian R., Farobie O., Hartulistiyoso E., Solihat N.N., Hua L.S.
Review, Bioresource Technology Reports, 2024, DOI Link
View abstract ⏷
Nonwood fibers are appealing substitutes for the raw materials for the pulp and paper sector, such as for packaging, whose market demand is growing, given their variety of sources and the decreasing trend of wood supply. To change the inherent hydrophilic properties of fibers, several specialty papers with additional features, such as hydrophobic qualities, have been actively produced globally. Compared with hydrophobic paper, superhydrophobic paper has a larger water contact angle (>150°), which endows it with superior capabilities, such as water repellence, anticorrosion, self-cleaning, anti-icing, drag reduction, and easy roll-off. This review presents the fundamentals of wettability, progress in preparing superhydrophobic nonwood papers, determination of the properties of superhydrophobic nonwood papers, characterization of superhydrophobic nonwood papers, and application of superhydrophobic nonwood papers. The future challenges, research, and development of superhydrophobic paper made from nonwood fibers are also briefly discussed. It is expected that durable superhydrophobic papers from non-wood sources can be produced using environmentally-friendly and economically-feasible technologies. Life cycle and techno-economic evaluations of superhydrophobic paper made from nonwood materials are recommended. The usage of these papers to replace plastic-based materials in food packaging and advanced applications like sensing devices would help to increase the use of sustainable materials.
Bioprospecting of multi-tasking fungi for a sustainable environment: Volume I
Uppuluri K.B., Selvasembian R.
Book, Bioprospecting of Multi-tasking Fungi for a Sustainable Environment: Volume I, 2024, DOI Link
View abstract ⏷
This book highlights the types and importance of multitasking fungi and provides critical analysis of fungi involved in production of important enzymes. It also covers additional tasks of fungi such as biosorption, remediation, soil fertilization, and water treatment. This book discusses the types of fungi, their cultivation, execution of multitasking, and the analysis and recovery of products. This information can be used to understand and improve the effectiveness and efficiency of fungi in the production of a variety of products, such as antibiotics, enzymes, and biofuels. This book would be of interest to researchers working in industrial biotechnology, fungal physiology, environmental sciences and technology, sustainable technologies, and agricultural sciences.
A combined bibliometric and sustainable approach of phytostabilization towards eco-restoration of coal mine overburden dumps
Bashir Z., Raj D., Selvasembian R.
Review, Chemosphere, 2024, DOI Link
View abstract ⏷
Extraction of coal through opencast mining leads to the buildup of heaps of overburden (OB) material, which poses a significant risk to production safety and environmental stability. A systematic bibliometric analysis to identify research trends and gaps, and evaluate the impact of studies and authors in the field related to coal OB phytostabilization was conducted. Key issues associated with coal extraction include land degradation, surface and groundwater contamination, slope instability, erosion and biodiversity loss. Handling coal OB material intensifies such issues, initiating additional environmental and physical challenges. The conventional approach such as topsoiling for OB restoration fails to restore essential soil properties crucial for sustainable vegetation cover. Phytostabilization approach involves establishing a self-sustaining plant cover over OB dump surfaces emerges as a viable strategy for OB restoration. This method enhanced by the supplement of organic amendments boosts the restoration of OB dumps by improving rhizosphere properties conducive to plant growth and contaminant uptake. Criteria essential for plant selection in phytostabilization are critically evaluated. Native plant species adapted to local climatic and ecological conditions are identified as key agents in stabilizing contaminants, reducing soil erosion, and enhancing ecosystem functions. Applicable case studies of successful phytostabilization of coal mines using native plants, offering practical recommendations for species selection in coal mine reclamation projects are provided. This review contributes to sustainable approaches for mitigating the environmental consequences of coal mining and facilitates the ecological recovery of degraded landscapes.
Insight into the biosorptive removal mechanisms of hexavalent chromium using the red macroalgae Gelidium sp.
Narayanan I., Kumar P.S., Franco D.S.P., Georgin J., Meili L., Selvasembian R.
Article, Biomass Conversion and Biorefinery, 2024, DOI Link
View abstract ⏷
Hexavalent chromium (Cr(VI)) is a highly toxic form of chromium, which can be found in industrial effluents from various sectors, such as the metallurgical, tanning, and pigment industries. The presence of Cr(VI) in the environment is a concern due to its negative effects on human health and the ecosystem since it is carcinogenic, mutagenic, and can cause damage to the respiratory, renal, hepatic, and dermatological systems. Adsorption is a sustainable alternative for the removal of Cr(VI) from the environment since it is an efficient, low-cost technique and can be adjusted according to specific environmental conditions. The use of algae biomass activated with chemical agents can be a promising solution to improve the adsorption capacity of the material and contribute to the mitigation of contamination by Cr(VI) and the protection of human health and the environment. The results of the study indicate that the activation of the red macroalgae Gelidium sp. with zinc chloride (ZnCl2) resulted in improvements in the adsorbent properties of the material for the removal of Cr(VI) in aqueous solutions. The physical characteristics of the material were analyzed, and it was observed that the surface area increased from 2.90 to 3.12 m2 g−1 after activation with ZnCl2. Furthermore, changes in the surface structure of the material were observed, with the presence of irregularities, mainly after the adsorption of Cr(VI). The analysis of functional groups indicated that the main groups present in the native biomass remained after activation with zinc, and new diffraction peaks also appeared, indicating the chemical modification of the material. The adsorption experiments were carried out under different conditions, such as pH, dosage, temperature, Cr(VI) concentration, and contact time. It was observed that the adsorption was favored under acidic conditions, with a dose of 0.05 g L−1 of activated biomass. Equilibrium was reached quickly in the first few minutes, and the general kinetic model best fitted the experimental data. The kinetic adsorption capacity was higher for the activated material (226 mg g−1) compared to the native material (114 mg g−1). Increasing the concentration of Cr(VI) in the solution resulted in an increase in the adsorption capacity, indicating that the driving force gradient was greater at higher concentrations of the contaminating ion. The isothermal data were well fitted by the Koble-Corrigan heterogeneous surface model, and the maximum adsorption capacities were estimated at 126 mg g−1 and 240 mg g−1 for native and activated biomass, respectively, at the highest Cr(VI) concentration studied (150 mg L−1). The results indicate that the activation of the red macroalgae Gelidium sp. with zinc chloride improved its adsorbent properties for the removal of Cr(VI) ions, with high adsorption capacity and efficiency, demonstrating a high potential for application in the removal of Cr(VI) metal ions in aqueous solutions. Graphical Abstract: (Figure presented.)
Mesoporous Activated Carbon from Sunflower (Helianthus annuus) Seed Pericarp for Crystal Violet Dye Removal: Numerical Desirability Optimization and Mechanism Study
Jawad A.H., Salleh N., ALOthman Z.A., Selvasembian R.
Article, Water, Air, and Soil Pollution, 2024, DOI Link
View abstract ⏷
In this work, sunflower (Helianthus annuus) seed pericarp (SSPC) was converted into mesoporous activated carbon (SSPCAC) via microwave-assisted ZnCl2 activation to be a cost-effective and renewable adsorbent for crystal violet (CV) dye removal. The obtained SSPCAC exhibits a preferable surface area of 641 m2/g with mesoporous characteristics. A statistical optimization by Box-Behnken Design (BBD) with Response Surface Methodology (RSM) was adopted to achieve the optimal operational conditions for CV dye including SSPCAC dose, solution pH, and contact time. Moreover, desirability functions confirm the maximum CV removal of 91% was attended at SSPC-AC dose (0.083 g/100 mL), solution pH (9.8), and contact time (5.38 min). Thus, the equilibrium data were best described by the Langmuir isotherm model with a maximum adsorption capacity of 111.9 mg/g at 25 0C. Thus, the adsorption kinetics were well described by a pseudo-second order (PSO) model. The adsorption mechanism of CV onto SSPCAC surface can be assigned to the electrostatic attraction, hydrogen bonding, pore filling, and pi-pi interactions. This research highlights the potential of sunflower seed pericarp as a renewable precursor for activated carbon production with promising applications in toxic dye removal from wastewater.
Insights into the recent advances of chemical pretreatment of waste activated sludge to enhance biomethane production
K A., Selvasembian R.
Review, Journal of Environmental Chemical Engineering, 2024, DOI Link
View abstract ⏷
Waste activated sludge (WAS) generated from wastewater treatment plants presents a significant environmental challenge due to its complex composition and disposal difficulties. In response, various strategies have been explored to manage sludge effectively, with renewable energy generation, particularly biomethane production via anaerobic digestion (AD), emerging as a promising solution. However, the hydrolysis stage, bottleneck in AD, hindering the degradation of complex organic molecules within WAS, necessitates innovative approaches. Chemical pretreatment methods have garnered attention for enhancing biomethane production efficiency. This review systematically assesses the efficacy of various chemical pretreatment approaches on WAS, examining their impacts on sludge composition, AD performance, and underlying mechanisms. Notably, the review underscores the influence of WAS characteristics, emphasizing the critical roles of dosage and pH in chemical pretreatment process. Moreover, it elucidates the synergistic potential of integrating chemical pretreatment with mechanical or biological methods, resulting in improved sludge degradability and enhanced biomethane yield. Additionally, the review emphasizes the importance of considering the characteristics and origins of sludge when selecting appropriate chemical pretreatment agents to optimize biomethane production. Furthermore, it highlights the potential benefits of implementing eco-friendly chemical pretreatment methods, which can mitigate the challenges faced by traditional chemical pretreatment approaches.
Mechanistic insights into the potential application of Scenedesmus strains towards the elimination of antibiotics from wastewater
Rajamanickam R., Selvasembian R.
Review, Bioresource Technology, 2024, DOI Link
View abstract ⏷
Scenedesmus strains have been reported to have the potential to tolerate and bioremediate antibiotic pollutants through bioadsorption, bioaccumulation, and biodegradation mechanism from the wastewater medium. Hormesis effects have been observed in the Scenedesmus strains when exposed to different concentrations of antibiotic pollutants. Lower concentrations of antibiotic pollutants are known to trigger growth-stimulating effects by triggering adaptive responses such as increased metabolic activity and activating detoxifying mechanisms leading to the biotransformation pathway. The present review examines the existing body of information pertaining to biotransformation pathways tolerance, hormesis effects, and efficiency of Scenedesmus strains in removing various antibiotic pollutants. This review provides critical information on using Scenedesmus species to treat antibiotic-polluted wastewater by boosting growth and resilience tolerant doses and avoiding toxicity at higher doses.
Recent advances in manipulating strategies of NH2-functionalized metallic organic frameworks-based heterojunction photocatalysts for the sustainable mitigation of various pollutants
Kaur B., Soni V., Kumar R., Singh P., Selvasembian R., Singh A., Thakur S., Parwaz Khan A.A., Kaya S., Nguyen L.H., Nguyen V.-H., Raizada P.
Review, Environmental Research, 2024, DOI Link
View abstract ⏷
NH2-functionalized metal-organic frameworks (NH2-functionalized MOFs) can abate organic pollutants, predominantly favored by their chemical, mechanical, and thermal stabilities. The present review stated the chemistry of identifying NH2-functionalization and its role in enhancing the properties of bare MOFs. The integration of the amine group bestows several advantages: 1.) enabling band structure modification, 2.) establishing strong metal-NH2 bonds, 3.) preserving MOF structures from reactive oxygen species, and 4.) shielding MOF structures against pH alterations. Consequently, the NH2-functionalized MOFs are promising materials for the photodegradation of organic contaminants. The following section illustrates the two approaches (pre-synthetic and post-synthetic) for NH2-functionalized MOFs. Nevertheless, specific intrinsic limitations, entailing a high recombination rate of charge carriers and inadequate optical adsorption, restrain the applicability of NH2-functionalized MOFs. Accordingly, the succeeding segment presents strategies to elevate the photocatalytic activities of NH2-functionalized MOFs via heterojunction fabrication. The importance of the NH2-functionalized MOFs-based heterojunction has been evaluated in terms of the effect on the enhancement of charge separation, optical adsorption, and redox ability of charge carriers. Subsequently, the potential application for organic pollutant degradation via NH2-functionalized MOFs-based heterojunctions has been scrutinized, wherein the organic pollutants. Eventually, the review concluded with challenges and potential opportunities in engaging and burgeoning domains of the NH2-functionalized MOFs-based heterojunctions.
Recent advances on Co3O4-based nanostructure photocatalysis: Structure, synthesis, modification strategies, and applications
Chauhan A., Kumar R., Devi S., Sonu, Raizada P., Singh P., Ponnusamy V.K., Sudhaik A., Mishra A.K., Selvasembian R.
Review, Surfaces and Interfaces, 2024, DOI Link
View abstract ⏷
Advanced oxidation processes, mainly photocatalysis, are utilized as an effective and alternative prospect for industrial wastewater treatment, especially in the non-biodegradable compounds. Among various photocatalysts, Co3O4 is a visible light active photocatalyst that exhibits superb photocatalytic activity in various photocatalytic applications. However, photocatalytic activity of bare Co3O4 nanoparticles remains inacceptable because of inherent shortcomings such as rapid recombination. Significant efforts were done in the last several years to advance performance and figure out the mechanisms involved. This review begins with structural & optical properties (and DFT studies), synthesis methods and goes detail about recent advances and strategies for refining the performance of Co3O4-based photocatalysts, for instance structural design and creation of Co3O4-based composites. Construction of Co3O4-based heterojunction results in a distinct photogenerated photocarriers mechanism, which reduces the recombination and increases photoactivity. The sole emphasis of this review is on the latest developments in environmental applications for Co3O4 as well as photocatalysts based on them. In conclusion, the varied environmental applications of Co3O4-based materials, such as pollutant degradation (i.e., dyes, antibiotics, phenols, pesticides, and Cr (VI) reduction) and energy conversion (e.g., H2 production, CO2 reduction/CO evolution, and O2 evolution), are summarized in detail. To summarize the bottlenecks, exciting challenges, current progress, and future perspectives for innovative opportunities are also presented.
A comprehensive review of lignin-reinforced lignocellulosic composites: Enhancing fire resistance and reducing formaldehyde emission
Iswanto A.H., Lee S.H., Hussin M.H., Hamidon T.S., Hajibeygi M., Manurung H., Solihat N.N., Nurcahyani P.R., Lubis M.A.R., Antov P., Savov V., Kristak L., Kawalerczyk J., Osvaldova L.M., Farid S., Selvasembian R., Fatriasari W.
Review, International Journal of Biological Macromolecules, 2024, DOI Link
View abstract ⏷
The rising environmental concerns and the growing demand for renewable materials have surged across various industries. In this context, lignin, being a plentiful natural aromatic compound that possesses advantageous functional groups suitable for utilization in biocomposite systems, has gained notable attention as a promising and sustainable alternative to fossil-derived materials. It can be obtained from lignocellulosic biomass through extraction via various techniques, which may cause variability in its thermal, mechanical, and physical properties. Due to its excellent biocompatibility, eco-friendliness, and low toxicity, lignin has been extensively researched for the development of high-value materials including lignin-based biocomposites. Its aromatic properties also allow it to successfully substitute phenol in the production of phenolic resin adhesives, resulting in decreased formaldehyde emission. This review investigated and evaluated the role of lignin as a green filler in lignin-based lignocellulosic composites, aimed at enhancing their fire retardancy and decreasing formaldehyde emission. In addition, relevant composite properties, such as thermal properties, were investigated in this study. Markedly, technical challenges, including compatibility with other matrix polymers that are influenced by limited reactivity, remain. Some impurities in lignin and various sources of lignin also affect the performance of composites. While lignin utilization can address certain environmental issues, its large-scale use is limited by both process costs and market factors. Therefore, the exact mechanism by which lignin enhances flame retardancy, reduces formaldehyde emissions, and improves the long-term durability of lignocellulosic composites under various environmental conditions remains unclear and requires thorough investigation. Life cycle analysis and techno-economic analysis of lignin-based composites may contribute to understanding the overall influence of systems not only at the laboratory scale but also at a larger industrial scale.
Recent updates on Ag2WO4-based S-scheme heterojunction photocatalytic materials for environmental remediation
Chauhan A., Kumar R., Sharma S., Raizada P., Sonu, Selvasembian R., Hussain C.M., Thakur S., Singh P., Sudhaik A.
Review, Inorganic Chemistry Communications, 2024, DOI Link
View abstract ⏷
Silver tungstate (Ag2WO4) as a captivating visible light active photocatalyst, is non-toxic in nature, chemically stable and possess good thermal stability. Extensive researches have lately centred on Ag2WO4 photoactivity for wastewater treatment. However, bare Ag2WO4 photocatalyst always showed low adsorption and high recombinant rate which inhibited its proficiency to work as a photocatalyst. So, recently, many advancement strategies have been introduced to overcome these difficulties such as doping, surface modification, conventional heterojunction, Z-scheme, and S-scheme heterojunction. But, in recent times, modern strategies including Z-scheme and S-scheme have attained typical consideration due to improved charge migration, and excellent light capture capability as well as longer the spatial life time of photocarriers while keeping the appropriate redox capability. So, this review offers an overview of current state-of-the-art in Ag2WO4-based heterojunctions and providing the insightful comments on the fabrication of these heterostructures. This review primarily focuses on structural and electronic properties via theoretical studies (DFT studies) as well as various synthesis methods to construct heterojunction of Ag2WO4. Also, exploration of different experimental approaches was done which provide confirmation for the operation of photocarriers migration between Ag2WO4 with another component. In addition, instances demonstrating the enhanced efficiency of Ag2WO4-based Z-scheme and S-scheme heterojunctions for several crucial photocatalytic processes includes dye colourization, antibiotic deterioration, heavy metal ions reduction, and bacterial disinfection. Designing rational Ag2WO4 heterojunction with small size particles and controlled morphology for suitable interfacial contact has received especial attention. Finally, the shortcomings of current research on Ag2WO4 based heterojunction photocatalysts are reviewed and prospected.
Co-pyrolysis of plastic waste and macroalgae Ulva lactuca, a sustainable valorization approach towards the production of bio-oil and biochar
Farobie O., Amrullah A., Fatriasari W., Nandiyanto A.B.D., Ernawati L., Karnjanakom S., Lee S.H., Selvasembian R., Azelee N.I.W., Aziz M.
Article, Results in Engineering, 2024, DOI Link
View abstract ⏷
To address the pressing demand for sustainable energy in light of environmental challenges, this study explored the synergetic effects of the co-pyrolysis of polyethylene terephthalate (PET) and Ulva lactuca macroalgae to yield bio-oil and biochar. The objective is to enhance the bio-oil quality for wider usability and to combat marine pollution. By employing co-pyrolysis, notable progress has been achieved in bio-oil yield and quality, particularly in hydrocarbon content, through the integration of PET. The highest bio-oil yield of 37.91 % was achieved under optimal conditions at 500 °C with a feedstock mixture consisting of 40 % U. lactuca and 60 % PET. Under these conditions, the bio-oil exhibited a significant increase in hydrocarbon content, reaching 57.16 %, which is essential for improving its energy potential. Biochar quality was also enhanced, with the biochar from a 70 % U. lactuca and 30 % PET blend showing a BET surface area of 20.18 m2/g, compared to the initial 1.38 m2/g of raw U. lactuca, indicating improved surface properties. This study presents a sustainable energy generation and environmental preservation approach, underscoring the potential of synergistically utilizing marine resources and plastic waste.
Exploring Ternary Deep Eutectic Solvent Pretreatment in a One-Pot Process with Napier Grass for Bioethanol Production
Narayanan K., Venkatachalam P., Panakkal E.J., Tantayotai P., Tandhanskul A., Selvasembian R., Chuetor S., Sriariyanun M.
Article, Bioenergy Research, 2024, DOI Link
View abstract ⏷
Effective pretreatment is essential for successfully utilizing renewable resources such as lignocellulosic biomass in the production of bioethanol. In this study, ternary deep eutectic solvents (DESs), namely choline chloride/lactic acid/glycerol (ChCl/LA/Gly), choline chloride/oxalic acid/glycerol (ChCl/OA/Gly), choline chloride/lactic acid/ethylene glycol (ChCl/LA/EG), and choline chloride/oxalic acid/ethylene glycol (ChCl/OA/EG) were prepared and employed for the pretreatment of cellulose-rich Napier grass (NG). Post treatment, the NG hydrolysate was subjected to enzymatic saccharification followed by ethanol fermentation. The results showed effective delignification of NG after treatment with the prepared ternary DESs, with ChCl/LA/EG removing a maximum of 92.89% lignin. The efficiency of the prepared DESs is attributed to their low densities, pH, and viscosity. Enzymatic saccharification of ChCl/LA/EG-treated NG resulted in a 1.68 fold increase in reducing sugar yield compared to that of untreated NG. All pretreated NG produced more bioethanol via a separate hydrolysis and fermentation (SHF) process than untreated NG after Saccharomyces cerevisiae fermentation. A maximum of 0.37 g bioethanol/g of biomass was obtained from the one-pot process using ChCl/LA/Gly pretreatment. FTIR and XRD analyses of untreated and pretreated NG corroborated the efficacy of the ternary DESs on cellulose recovery and delignification. Also, enzymatic and microbial inhibition studies on the prepared DESs show their potential to be employed in a one-pot process for biorefinery. The results of the present investigation show the potential of utilizing eco-friendly DESs and renewable resources for the production of bioethanol, a viable option to fossil fuels.
Co-immobilization of magnesium precursor and Candida rugosa lipase on alumina via covalent bonding for biodiesel production
Ramlee N.N., Md Illias R., Toemen S., Rahman R.A., Selvasembian R., Fatriasari W., Ghazali N.F., Wan Azelee N.I.
Article, Fuel, 2024, DOI Link
View abstract ⏷
Catalyst development is one of the most challenging aspects in biodiesel production due to the compatibility issue with the feedstocks and catalyst poisoning upon exposure to process conditions. In the present research, chemoenzymatic catalyst was prepared by impregnation of magnesium aluminate (MA) on alumina support, modifying the support using activating agent, and immobilization of Candida rugosa lipase (CRL) onto the support. The optimum immobilization condition was resulting in 85.07 % of activity recovery of immobilized lipase, equivalent to 30.53 % of immobilization efficiency. The catalysts were characterized through XRD, FTIR, FESEM-EDX, NAA and CO2-TPD confirming the mixture of AlO(OH), magnesium aluminate (MA), (MgNO3)2 and Mg2+ on the support. CRL/L-lysine/MA showed remarkable improvement in thermal stability (40 − 70℃), solvents tolerance (ethanol, methanol, isopropanol, tert-butanol), and storage stability at 30 ℃, as compared to free CRL. CRL/L-lysine/MA successfully produced biodiesel yield up to 87.10 % at 200.71 rpm of agitation speed, 13.58 % (w/w) of water content, 10 h reaction time, 15 % (w/w) of catalyst loading, at 50 ℃, using 1:12 of oil to methanol molar ratio, and retaining 46.60 % of biodiesel yield after six cycle. The CRL/L-lysine/MA demonstrated novel catalysts characteristics comprising chemical and biological active species on a single support for biodiesel production from waste cooking oil (WCO).
Removal of dyes from water using Citrullus lanatus seed powder in continuous and discontinuous systems
Grassi P., Georgin J., S. P. Franco D., Sa I.M.G.L., Lins P.V.S., Foletto E.L., Jahn S.L., Meili L., Rangabhashiyam S.
Article, International Journal of Phytoremediation, 2023, DOI Link
View abstract ⏷
The objective of this study is to develop a low-cost biosorbent using residual seeds of the Citrullus lanatus fruit for the removal of cationic dyes. Physicochemical parameters such as pH, adsorbent mass, contact time, and temperature were evaluated for their effects on dye removal. The biosorbent is composed of lignin and cellulose, exhibiting a highly heterogeneous surface with randomly distributed cavities and bulges. The adsorption of both dyes was most effective at natural pH with a dosage of 0.8 g L−1. Equilibrium was reached within 120 min, regardless of concentration, indicating rapid kinetics. The Elovich model and pseudo-second-order kinetics were observed for crystal violet and basic fuchsin dye, respectively. The Langmuir model fitted well with the equilibrium data of both dyes. However, the increased temperature had a negative impact on dye adsorption. The biosorbent also demonstrated satisfactory performance (R = 43%) against a synthetic mixture of dyes and inorganic salts, with a small mass transfer zone. The adsorption capacities for crystal violet and basic fuchsin dye were 48.13 mg g−1 and 44.26 mg g−1, respectively. Thermodynamic studies confirmed an exothermic nature of adsorption. Overall, this low-cost biosorbent showed potential for the removal of dyes from aqueous solutions.
Applications of graphitic carbon nitride-based S-scheme heterojunctions for environmental remediation and energy conversion
Sudhaik A., Sonu, Hasija V., Selvasembian R., Ahamad T., Singh A., Khan A.A.P., Raizada P., Sing P.
Review, Nanofabrication, 2023, DOI Link
View abstract ⏷
The contemporary era’s top environmental problems include the lack of energy, recycling of waste resources, and water pollution. Due to the speedy growth of modern industrialization, the utilization of non-renewable sources has increased rapidly, which has caused many serious environmental and energy issues. In photocatalysis, as a proficient candidate, g-C3 N4 (metal-free polymeric photocatalyst) has gained much attention due to its auspicious properties and excellent photocatalytic performance. But, regrettably, the quick recombination of pho-toinduced charge carriers, feeble redox ability, and inadequate visible light absorption are some major drawbacks of g-C3 N4 that hamper its photocatalytic ability. Henceforth, these significant limitations can be solved by incorporating modification strate-gies. Among all modification techniques, the amalgamation of g-C3 N4 with two or more photocatalytic semiconducting materials via heterojunction formation is more advantageous. In this review, we have discussed various modification strategies, including conventional, Z-scheme and S-scheme heterojunctions. S-scheme heterojunction is consideredan efficient and profit-able charge transferal pathway due to the excellent departure and transferal of photoexcited charge carriers with outstanding redox ability. Consequently, the current review is focused on various photocatalytic applications of S-scheme-based g-C3 N4 photocatalysts in pollutant degradation, H2 production, and CO2 reduction.
Thermochemical processes for resource recovery from municipal wastewater treatment plants
Arun C., Sethupathy A., Rangabhashiyam S., Sharma R., Karthikeyan S., Ramprasad C.
Book chapter, Resource Recovery in Municipal Waste Waters, 2023, DOI Link
View abstract ⏷
Waste is a cross-cutting concern as it imposes serious threats to the environment and local habitats. Therefore, the recognition and inclusion of effective waste management strategies in decision-making are fundamental to achieving sustainable development goals. Waste management enables communities to resource recovery from waste and promotes zero waste concepts. In the recent past, several potential point sources have been identified for resource recovery from waste. Municipal wastewater treatment plants (MWTPs) are at the very core of such sources, as treated sewage in such plants is a highly reliable, low-cost, and gigantic feedstock. Being a promising renewable energy source, biomass available at MWTPs and its conversion into biofuels is, however, widely studied. Thermochemical methods are highly advantageous for harvesting biofuels owing to their versatile nature, high production yield from feedstock, cost-effectiveness, environmental benignity, lower footprints, and efficiency in producing fungible liquid fuels. Here, in this chapter, basic thermochemical processes are emphasized to illustrate the conversion of organic and biomass of MWTPs into biofuels like biochar, biogas, etc. The first part of the chapter presents an overview of the different chemicals and materials that can be obtained from MWTPs. Afterward, a description of various thermochemical methods like pyrolysis, gasification, and hydrothermal techniques has been provided for a deeper understanding of the field. At last, recent advancements, challenges, and future aspects of the approach have been discussed.
Green soap formulation: an insight into the optimization of preparations and antifungal action
Thirunavukkarasu A., Nithya R., Sivashankar R., Sathya A.B., Rangabhashiyam S., Pasupathi S.A., Prakash M., Nishanth M.
Article, Biomass Conversion and Biorefinery, 2023, DOI Link
View abstract ⏷
Ultrasound-assisted extract of Acalypha indica was used to prepare the green soap formulation. Previously, D-optimal mixture design was used to optimize the mixture of oil components including coconut oil (A, 34–56%), soybean oil (B, 19–31%), castor oil (C, 14–23%), sunflower oil (D, 4–6%), and olive oil (E, 5–9%). Linear regression models were proposed to predict the responses, i.e., hardness (Y1), iodine (Y2), and iodine number saponification (INS) (Y3), and validated with a high degree of statistical accuracy (Fcal > Ftab; df = 4, p < 0.0001; R2 > 0.9950). Optimization results revealed that the formulation containing 44.57% A, 23.62% B, 17.44% C, 5.37% D, and 9.0% E would yield 41 Y1, 62 Y2, and 159 Y3. The chemical properties of the optimized soap formulation were quite comparable concerning the standard soap specifications (IS13498). Further, this formulation was supplemented with Acalypha indica extract to prepare the green soap, and its antifungal activity was determined using the agar dilution method. [Figure not available: see fulltext.].
Nanoparticles for the adsorptive removal of heavy metals from wastewater
Azelee N.I.W., Rosli A., Ayothiraman S., Mishra S., Sundaram B., Selvasembian R.
Book chapter, Adsorption through Advanced Nanoscale Materials: Applications in Environmental Remediation, 2023, DOI Link
View abstract ⏷
Nanotechnology is one of the most innovative and fascinating domains of science and technology. The application of nanotechnology to engineering enables creation of nanomaterials with unique qualities for a variety of engineering applications that have been established and used for human advancement. In the past few years, it has proved its ability to contribute to one of the most important environmental concerns, wastewater treatment. In recent years, several novel nanoparticle adsorbents have been proposed to improve the efficacy and adsorption capabilities of harmful contaminants from wastewater. The current research looks at using Nanoparticles as a nanoadsorbent to remove heavy metals from wastewater. The fundamentals of adsorption, as well as a variety of nanoadsorbents often utilized in wastewater treatment, are discussed in this work. The goal of this chapter is to highlight the importance of adsorption, various Nanoparticles synthesis methods and their application in the field of wastewater treatment.
Preface
Selvasembian R., Thokchom B., Singh P., Jawad A.H., Gwenzi W.
Editorial, Remediation of Heavy Metals: Sustainable Technologies and Recent Advances, 2023,
Advanced Functional Materials and Methods for Photodegradation of Toxic Pollutants
Mishra A.K., Singh P., Raizada P., Vadivel S., Selvasembian R.
Book, Advanced Functional Materials and Methods for Photodegradation of Toxic Pollutants, 2023, DOI Link
View abstract ⏷
Advanced Functional Materials and Methods for Photodegradation of Toxic Pollutants addresses the potential role of visible active photocatalytic methods for the removal of various emerging and persistent organic pollutants (POPs.) Describing the classification, sources and potential risks of emerging organics in water bodies and the environment, the book covers the different synthesis methods of visible active structured photocatalysts and structure related properties to their applications in photocatalytic processes for the removal of antibiotics, pharma and heavy metal pollutants. This book provides an invaluable reference to academics, researchers and technicians in chemical engineering, chemistry and environmental science. In addition, the mechanistic insights associated with the interaction of advanced functional materials and water pollutants along with the possible reaction pathway occurring during the visible light induced photocatalytic processes together with toxicity are discussed in detail along with the reutilization of catalysts, supporting the inherent reaction conditions performed with natural conditions.
Box–Behnken design with desirability function for methylene blue dye adsorption by microporous activated carbon from pomegranate peel using microwave assisted K2CO3 activation
Reghioua A., Jawad A.H., Selvasembian R., ALOthman Z.A., Wilson L.D.
Article, International Journal of Phytoremediation, 2023, DOI Link
View abstract ⏷
This research aims to convert pomegranate peel (PP) into microporous activated carbon (PPAC) using a microwave assisted K2CO3 activation method. The optimum activation conditions were carried out with a 1:2 PP/K2CO3 impregnation ratio, radiation power 800 W, and 15 min irradiation time. The statistical Box–Behnken design (BBD) was employed as an effective tool for optimizing the factors that influence the adsorption performance and removal of methylene blue (MB) dye. The output data of BBD with a desirability function indicate a 94.8% removal of 100 mg/L MB at the following experimental conditions: PPAC dose of 0.08 g, solution pH of 7.45, process temperature of 32.1 °C, and a time of 30 min. The pseudo-second order (PSO) kinetic model accounted for the contact time for the adsorption of MB. At equilibrium conditions, the Freundlich adsorption isotherm describes the adsorption results, where the maximum adsorption capacity of PPAC for MB dye was 291.5 mg g−1. This study supports the utilization of biomass waste from pomegranate peels and conversion into renewable and sustainable adsorbent materials. As well, this work contributes to the management of waste biomass and water pollutant sequestration.
Preface
Selvasembian R., Azelee N.I.W., Shanmugam S.R., Venkatachalam P., Mishra A.K.
Editorial, Valorization of Wastes for Sustainable Development: Waste to Wealth, 2023, DOI Link
Remediation of Heavy Metals: Sustainable Technologies and Recent Advances
Selvasembian R., Thokchom B., Singh P., Jawad A.H., Gwenzi W.
Book, Remediation of Heavy Metals: Sustainable Technologies and Recent Advances, 2023, DOI Link
View abstract ⏷
Remediation of Heavy Metals Meet the challenge of contaminated water with a range of sustainable tools The treatment of water which has been polluted by heavy metals is an increasingly significant environmental challenge in an industrialized global economy. The ongoing revolution in green technologies, however, has seen a range of sustainable methods emerge for treating water, soils, and other parts of the environment polluted by trace metals. By putting these methods into practice, environmental researchers and industrial professionals can improve water quality, and public health globally. Remediation of Heavy Metals offers a clear, accessible reference on these methods and their applications. It offers an overview of the major effects of heavy metal contamination and works through each of the methods or protocols available to remediate soil and minimize pollution at the source. Remediation of Heavy Metals readers will also find: Comparison of different approaches for heavy metal removal Detailed discussion of physical, chemical, and biological remediation methods Case studies demonstrating proper remediation Remediation of Heavy Metals provides key knowledge for environmental scientists, environmental toxicologists, and other researchers or industrial professionals working in heavy metal removal, as well as advanced graduate students in these areas.
Traditional techniques of water purification in rural areas
Dulta K., Iwuchukwu F.U., Kumari S., Narayanasamy S., Selvasembian R.
Book chapter, Water Resources Management for Rural Development: Challenges and Mitigation, 2023, DOI Link
View abstract ⏷
Water is the lifeline of all living forms on earth, meeting the demand for drinking water and acquiring safe water is a pipe dream for the majority of people in the world as well as a big issue too. There are lots of challenges accustomed to the availability of drinking water due to increasing problems like intense urbanization, chemical product usage, and the presence of emerging contaminants. From the review done in the paper, groundwater is noted to have better quality than surface waters but is lacking in terms of agricultural run-offs percolation and inappropriate disposal of domestic effluents. As much as there are several kinds of water treatment technologies available for treating water, these systems would be inappropriate or too expensive for a large population in developing countries rural areas, and underdeveloped countries. More research interests are growing in water microbiological quality and lowering waterborne diseases. All of these approaches are essentially intended to remove pollutants and contaminants from water adsorb them and in turn, make them safe for drinking. This chapter discusses traditional practices like sedimentation, solar disinfection, and various filtration methods that are widely used in rural areas. However, rural treatments of water differ according to climate, water resources, quality, adaptability of treatment methods, and skills of the people implementing the techniques.
Life cycle assessment of LDH-MgFe production for nitrate removal: impacts of synthesis methods
da Silva A.F., da Silva Duarte J.L., Selvasembian R., Meili L.
Article, Journal of Nanoparticle Research, 2023, DOI Link
View abstract ⏷
Layered double hydroxides (LDHs) form a suitable structure for nitrate removal in aqueous solution. Its synthesis can be obtained by different methods, under different conditions, such as hydrothermal treatment and coprecipitation, a more conventional method. However, the investigation of the possible environmental impacts of each synthetic route has not yet been reported in the literature and, for that, we conducted a simplified life cycle assessment (LCA) of LDH-MgFe production, to identify the main environmental impacts associated with each route of synthesis. The approach was employed on a work scale, investigating coprecipitation, hydrothermal, ultrasound, and microwave methods, with the aid of the openLCA 1.10.3 software, using data from the ecoinvent database v.3, based on the CML 2000 methodology (midpoint). Thus, this study presented the possibility of identifying the main environmental impacts for each synthesis method as a function of the nitrate removal capacity of each produced adsorbent. The results of the LCA comparison showed that the adsorbents obtained by coprecipitation and ultrasound syntheses had the lowest environmental impacts for all tested indicators: acidification potential, eutrophication, ozone layer destruction potential, and human toxicity. In addition, sodium hydroxide and electricity, product and input energy of the LDH production process, would contribute significantly to the increase in the impact on all synthesized adsorbents.
Valorization of Wastes for Sustainable Development: Waste to Wealth
Selvasembian R., Azelee N.I.W., Shanmugam S.R., Venkatachalam P., Mishra A.K.
Book, Valorization of Wastes for Sustainable Development: Waste to Wealth, 2023, DOI Link
View abstract ⏷
Valorization of Wastes for Sustainable Development: Waste to Wealth highlights the various valorization of organic and non-organic waste to offer a way forward to a sustainable world. Categorizing the various types of waste valorization for renewable fuel production and other valorizations utilizing organic and non-organic waste, this book offers the reader a comprehensive view of various waste valorizations together with their potential applications. Split into four sections, the book's chapters cover the general scenarios and challenges of current waste management and the valorization of waste specifically for renewable fuels as the alternative energy source to depleting fossil fuels. Other chapters cover waste valorizations categorized into organic and non-organic waste for various applications and the future prospect of waste valorizations with possible plans and strategies for effective global waste management.
Waste Musa acuminata residue as a potential biosorbent for the removal of hexavalent chromium from synthetic wastewater
Hariharan A., Harini V., Sandhya S., Rangabhashiyam S.
Article, Biomass Conversion and Biorefinery, 2023, DOI Link
View abstract ⏷
The present study is undertaken to evaluate the feasibility use of Musa acuminata bract as (MAB) biosorbent towards the removal of hexavalent chromium from synthetic wastewater. Chromium is a potential pollutant to all forms of life and therefore efficient way of treatment is necessary even towards lower chromium concentration removal. The objectives of the present research include optimizing parameters influencing biosorption of hexavalent chromium, pH, dosage of the MAB, influent Cr(VI) concentration, and time. The MAB was characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM) analysis, to examine the surface functional group and structural assessments of the MAB. Optimum pH for the effective biosorption was found to be 2.0, and the biosorption capacity was found to be 36.84 mg/g with 87.55% of Cr(VI) removal. Further experiments were carried out at the optimized pH for other parameters influence on the Cr(VI) biosorption. Langmuir isotherm shows better fit than the rest of the models because of the higher R2 value. The data were analyzed using pseudo-first-order, pseudo-second-order, intra-particle diffusion, and Elovich models. Higher degree of coefficient of determination was obtained for the pseudo-second-order kinetic model. The results of the present study suggested that MAB could be used beneficially in treating industrial effluents containing hexavalent chromium through further research study of column biosorption.
Lignocellulosic Biomass Refining for Second Generation Biofuel Production
Ponnusami V., Uppuluri K.B., Rangabhashiyam S., Singh P.
Book, Lignocellulosic Biomass Refining for Second Generation Biofuel Production, 2023, DOI Link
View abstract ⏷
This book compiles research aspects of second-generation (2G) biofuel production derived specifically from lignocellulose biomass using biorefinery methods. It focuses on the valorization of different sources of 2G biofuels and their relative importance. The constituents of lignocelluloses and their potential characteristics different methods of treating lignocellulose, various means of lignocellulose bioconversion, and biofuel production strategies are discussed. Features: •Describes technological advancements for bioethanol production from lignocellulosic waste •Provides the roadmap for the production and utilization of 2G biofuels •Introduces the strategic role of metabolic engineering in the development of 2G biofuels •Discusses technological advancements, life cycle assessment, and prospects •Explores the novel potential lignocellulosic biomass for 2G biofuels This book is aimed at researchers and professionals in renewable energy, biofuel, bioethanol, lignocellulose conversion, fermentation, and chemical engineering.
Microbial fuel cells as an energy-efficient alternative for pollution degradation
Saranya N., Rangabhashiyam S.
Book chapter, Resource Recovery in Industrial Waste Waters, 2023, DOI Link
View abstract ⏷
Treatment of wastewater and generation of energy are major challenges faced by many countries. This chapter examines the treatment of industrial-related pollution using an energy recovery technology that addresses the problems of both industrial wastewater treatment and electricity. Microbial fuel cells (MFCs) represent an innovative sustainable technology solution that generates bioenergy and simultaneously treats wastewater. MFCs are associated with the merits of low-cost factors and eco-friendly approaches. The chapter presents different configurations and working of MFCs, important parameters, electrode materials, proton exchange membranes, and recent analysis. Further, the most indispensable approach of the MFC-based technology discussed serves as sustainable means toward the treatment of industrial wastewater.
Recent advances in cellulose supported photocatalysis for pollutant mitigation: A review
Sudhaik A., Raizada P., Ahamad T., Alshehri S.M., Nguyen V.-H., Van Le Q., Thakur S., Thakur V.K., Selvasembian R., Singh P.
Review, International Journal of Biological Macromolecules, 2023, DOI Link
View abstract ⏷
In recent times, green chemistry or “green world” is a new and effective approach for sustainable environmental remediation. Among all biomaterials, cellulose is a vital material in research and green chemistry. Cellulose is the most commonly used natural biopolymer because of its distinctive and exceptional properties such as reproducibility, cost-effectiveness, biocompatibility, biodegradability, and universality. Generally, coupling cellulose with other nanocomposite materials enhances the properties like porosity and specific surface area. The polymer is environment-friendly, bioresorbable, and sustainable which not only justifies the requirements of a good photocatalyst but boosts the adsorption ability and degradation efficiency of the nanocomposite. Hence, knowing the role of cellulose to enhance photocatalytic activity, the present review is focused on the properties of cellulose and its application in antibiotics, textile dyes, phenol and Cr(VI) reduction, and degradation. The work also highlighted the degradation mechanism of cellulose-based photocatalysts, confirming cellulose's role as a support material to act as a sink and electron mediator, suppressing the charge carrier's recombination rate and enhancing the charge migration ability. The review also covers the latest progressions, leanings, and challenges of cellulose biomaterials-based nanocomposites in the photocatalysis field.
Reuse of water treatment plant sludge for treatment of pollutants
Nandan A., Rangabhashiyam S.
Book chapter, Resource Recovery in Drinking Water Treatment, 2023, DOI Link
View abstract ⏷
By-products obtained through the industrial and municipal wastewater treatment process are called sewage sludge; they are rich in various sources of important compounds and nutrients. Various sources through which sludge is generated are mechanical, chemical, and biological treatment techniques of wastewater. Due to rapid urbanization and industrialization, this generated sludge poses a major threat to the environment. This generated sludge has a variety of organic and inorganic chemicals and pathogens. Nowadays this waste sludge has to undergo dewatered technique and then disposed of in a landfill as a result of which the pollutant present in the sludge and its problem are shifting from a liquid state to a solid state. The organic insoluble pollutants produced by industry can be the prime resource of energy and thus should be used in various forms. Due to its high-energy value, sludge can be made to be used as fertilizer or soil conditioner for agriculture purposes and adsorbent in the form of biochar to remove trace metals and dyes. Initially, sludge produced from wastewater treatment was considered a waste product because of the expected high amount of contaminants but a recent study suggests sustainable use of sewage sludge like use as a component of clinker meals in cement plants, ceramic adhesive, can be used to remove heavy metals, gases pollutant, and organic matter from water. This study is an approach to catalog multiple sewage applications and their sustainable approaches to using has been discussed.
Emerging trends in the pretreatment of microalgal biomass and recovery of value-added products: A review
Pradhan N., Kumar S., Selvasembian R., Rawat S., Gangwar A., Senthamizh R., Yuen Y.K., Luo L., Ayothiraman S., Saratale G.D., Mal J.
Article, Bioresource Technology, 2023, DOI Link
View abstract ⏷
Microalgae are a promising source of raw material (i.e., proteins, carbohydrates, lipids, pigments, and micronutrients) for various value-added products and act as a carbon sink for atmospheric CO2. The rigidity of the microalgal cell wall makes it difficult to extract different cellular components for its applications, including biofuel production, food and feed supplements, and pharmaceuticals. To improve the recovery of products from microalgae, pretreatment strategies such as biological, physical, chemical, and combined methods have been explored to improve whole-cell disruption and product recovery efficiency. However, the diversity and uniqueness of the microalgal cell wall make the pretreatment process more species-specific and limit its large-scale application. Therefore, advancing the currently available technologies is required from an economic, technological, and environmental perspective. Thus, this paper provides a state-of-art review of the current trends, challenges, and prospects of sustainable microalgal pretreatment technologies from a microalgae-based biorefinery concept.
An ecotoxicological perspective of microplastics released by face masks
Cabrejos-Cardena U., De-la-Torre G.E., Dobaradaran S., Rangabhashiyam S.
Article, Journal of Hazardous Materials, 2023, DOI Link
View abstract ⏷
The accelerated use, massive disposal, and contamination with face masks during the COVID-19 pandemic have raised new questions regarding their negative impact on the environment emerged. One major concern is whether microplastics (MPs) derived from face masks (FMPs) represent an important ecotoxicological hazard. Here, we discussed the shortcomings, loose ends, and considerations of the current literature investigating the ecotoxicological effects of FMPs on aquatic and terrestrial organisms. Overall, there are multiple uncertainties regarding the true impact of FMPs at a certain concentration due to the presence of uncontrolled or unknown degradation products, such as MPs of various size ranges even nano-sized (<1 µm) and chemical additives. It is apparent that FMPs may induce endocrine-disrupting and behavioral effects in different organisms. However, the results of FMPs should be carefully interpreted, as these cannot be extrapolated at a global scale, by taking into account a number of criteria such as face mask manufacturers, providers, consumer preferences, and type of face masks. Considering these uncertainties, it is still not possible to estimate the contribution of face masks to the already existing MP issue.
Formaldehyde production using methanol and heterogeneous solid catalysts: A comprehensive review
Mahdi H.I., Ramlee N.N., Santos D.H.D.S., Giannakoudakis D.A., de Oliveira L.H., Selvasembian R., Azelee N.I.W., Bazargan A., Meili L.
Review, Molecular Catalysis, 2023, DOI Link
View abstract ⏷
Despite formaldehyde's high toxicity, it has widespread demand worldwide due to its applications in the synthesis of a plethora of important chemicals like urea-formaldehyde, paraformaldehyde, polyacetal, and biological reagents amongst others. Currently, silver and iron molybdenum oxide catalysts are mostly utilized industrially due to their excellent efficiency and stability. As the catalyst ages and becomes saturated, selectivity decreases, pressure-drop increases, and the temperature of the heat transfer fluid rises. This review aims to present a comprehensive summary of formaldehyde production, considering the fundamentals of the process with a focus on decreasing methanol consumption and the utilization of natural zeolites as renewable, cost-efficiency, abundant and reusable catalysts.
A comprehensive review on nanocatalysts and nanobiocatalysts for biodiesel production in Indonesia, Malaysia, Brazil and USA
Mahdi H.I., Ramlee N.N., da Silva Duarte J.L., Cheng Y.-S., Selvasembian R., Amir F., de Oliveira L.H., Wan Azelee N.I., Meili L., Rangasamy G.
Article, Chemosphere, 2023, DOI Link
View abstract ⏷
Biodiesel is an alternative to fossil-derived diesel with similar properties and several environmental benefits. Biodiesel production using conventional catalysts such as homogeneous, heterogeneous, or enzymatic catalysts faces a problem regarding catalysts deactivation after repeated reaction cycles. Heterogeneous nanocatalysts and nanobiocatalysts (enzymes) have shown better advantages due to higher activity, recyclability, larger surface area, and improved active sites. Despite a large number of studies on this subject, there are still challenges regarding its stability, recyclability, and scale-up processes for biodiesel production. Therefore, the purpose of this study is to review current modifications and role of nanocatalysts and nanobiocatalysts and also to observe effect of various parameters on biodiesel production. Nanocatalysts and nanobiocatalysts demonstrate long-term stability due to strong Brønsted-Lewis acidity, larger active spots and better accessibility leading to enhancethe biodiesel production. Incorporation of metal supporting positively contributes to shorten the reaction time and enhance the longer reusability. Furthermore, proper operating parameters play a vital role to optimize the biodiesel productivity in the commercial scale process due to higher conversion, yield and selectivity with the lower process cost. This article also analyses the relationship between different types of feedstocks towards the quality and quantity of biodiesel production. Crude palm oil is convinced as the most prospective and promising feedstock due to massive production, low cost, and easily available. It also evaluates key factors and technologies for biodiesel production in Indonesia, Malaysia, Brazil, and the USA as the biggest biodiesel production supply.
Face mask structure, degradation, and interaction with marine biota: A review
De-la-Torre G.E., Dioses-Salinas D.C., Pizarro-Ortega C.I., Fernandez-Severini M.D., Forero-Lopez A.D., Dobaradaran S., Selvasembian R.
Article, Journal of Hazardous Materials Advances, 2023, DOI Link
View abstract ⏷
The COVID-19 pandemic signified an unprecedented driver of plastic pollution, mainly composed of single-use face masks (FMs). Aiming to understand their negative impact (whether aged or not)on the trophic chain, biotic (e.g., bio-incrustation) and abiotic factors (e.g., UV-light, mechanical abrasion) which affect the toxicological profile of FMs or their sub-products (mainly microplastics, MPs, and nanoplastics, PNPs) were studied. In addition to the capacity of FMs to be an immediate source of MPs/PNPs, according to reports in the scientific literature, they are also good substrates since they tend to facilitate the proliferation and transport of eukaryotic and prokaryotic organisms, pathogens such as the SARS-CoV-2 virus, contaminating water sources and facilitating the enrichment and spread of antibiotic resistance genes (ARG) in the environment. However, there is limited research on macrofouling and species dispersal. Therefore, the present review aimed to provide an updated and summarized analysis of the environmental and ecotoxicological contribution of this type of waste as well as literature regarding face mask degradation and MPs and/or PNPs release, interaction with biota, colonization in addition to recommendations for future studies.
Correction to: Cadmium removal by composite copper oxide/ceria adsorbent from synthetic wastewater (Biomass Conversion and Biorefinery, (2023), 13, 9, (7633-7642), 10.1007/s13399-021-01534-6)
Pal D.B., Selvasembian R., Singh P.
Erratum, Biomass Conversion and Biorefinery, 2023, DOI Link
View abstract ⏷
It may kindly be noted that unintentionally and last minute human error, wrong figures were incorporated during the submission of the manuscript and the same mistake could not be traced during the submission of the corrected proofs. The original article has been corrected.
Valorization of microwave-assisted H3PO4-activated plantain (Musa paradisiacal L) leaf biochar for malachite green sequestration: models and mechanism of adsorption
Jabar J.M., Adebayo M.A., Odusote Y.A., Yilmaz M., Rangabhashiyam S.
Article, Results in Engineering, 2023, DOI Link
View abstract ⏷
Utilization of synthetic dyes in different sectors has been identified as one of the major sources of environmental degradation; as a result, removal of their remnants from the industrial effluent is highly encouraged for conserving our environment. In this study, the synthesized plantain leaf biochar (PLB) was used for adsorbing synthetic malachite green (MG). The synthesized PLB was characterized through pHpzc, BET, XRD, SEM and FTIR spectrometry. The sequestration of MG onto PLB confirmed by FTIR and SEM was optimized by varying the adsorption parameters. The BET surface area (986.35 m2/g) and average pore diameter (44.13 Å) showcased PLB as an efficient mesoporous biochar capable of adsorbing MG (>99%) at optimum conditions of pH (8.0), initial MG concentration (50 mg/L), adsorbent dosage (0.2 g/L), contact time (80 min) and temperature of 301 K. Redlich-Peterson and Avrami fractional model best fitted the adsorption isotherm and kinetic model, respectively. ΔGo and ΔHo being negative confirmed the feasibility and exothermic nature of the adsorption process. The outstanding regeneration (>97%) of PLB after the fifth regeneration cycle established PLB as a potential sustainable green adsorbent for future industrial wastewater treatment.
Cadmium removal by composite copper oxide/ceria adsorbent from synthetic wastewater
Pal D.B., Selvasembian R., Singh P.
Article, Biomass Conversion and Biorefinery, 2023, DOI Link
View abstract ⏷
Composite copper–ceria-based adsorbent prepared by different sol–gel and co-precipitation methods and their performances were examined for cadmium removal from aqueous solution. Cadmium as a pollutant in drinking water is a severe problem that has negative health effects on humans. In the present study, the prepared adsorbents were characterized using a particle size analyzer, BET surface area, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) analysis. TEM analysis revealed the presence of approximately hexagonal-shaped copper oxide ceria with size ranging from 15 to 20 nm and having an average size distribution of 15.45 nm for sol–gel and 16.79 nm for co-precipitation prepared adsorbents. Synthesized adsorbents obtained using the sol–gel method showed better cadmium removal than those obtained using co-precipitation methods. Adsorption data of adsorption isotherm and kinetic models were analyzed. Cadmium’s adsorption was more rapid in the sol–gel copper oxide ceria adsorbent compared to the co-precipitation copper oxide ceria adsorbent. Equilibrium was attained quickly because of the higher surface area of CuO/CeO2 prepared by the sol–gel method. The equilibrium adsorption capability of sol–gel copper oxide ceria was more than 93%, while the co-precipitation copper oxide ceria’s equilibrium adsorption capability was approximately 89%. The prepared copper–ceria composite adsorbents showed good performance toward cadmium removal from aqueous solutions.
Pyrolysis of an invasive weed Prosopis juliflora wood biomass for the adsorptive removal of ciprofloxacin
Subramaniyasharma S., Shanmugam S.R., Bhuvaneswari V., Ponnusami V., Rangabhashiyam S.
Article, Biomass Conversion and Biorefinery, 2023, DOI Link
View abstract ⏷
In recent years, the buildup of antibiotic residues in freshwater and wastewater systems has become a significant environmental problem. The fluorinated quinolone-based drug ciprofloxacin (CIP) is a persistent organic pollutant in freshwater and wastewater streams with broad spectrum antibacterial action. Prosopis juliflora is an environmentally invasive weed that has invaded India’s thousands of hectares of land. In the present investigation, Prosopis juliflora biochar (PJB) was prepared by pyrolysis at a temperature of 550 °C under inert conditions, and the prepared biochar was activated with ZnCl2. The adsorption data of CIP onto synthesized activated biochar was then examined by fitting to adsorption isotherm and kinetic models. The effects of different adsorption parameters (pH, adsorbent dosage, temperature, and initial CIP concentration) were investigated. Prepared PJB-AC had a specific surface area of 360.5 m2/g. The isotherm model fitting results showed that the PJB-AC exhibited a comparable adsorption performance (158.2 mg/g) compared to commercially available activated carbon (147.5 mg/g) towards CIP removal. Kinetic regression results showed that the CIP adsorption was well described by a pseudo-second-order kinetic model indicating chemical adsorption of CIP. This is the first study that reported on understanding the adsorption characteristics of various forms of Prosopis julifora biomass (PJ, PJB, and PJB-AC) on CIP removal from aqueous solutions. The results from this study indicate that PJB-AC is a promising adsorbent for CIP removal. Graphical Abstract: [Figure not available: see fulltext.]
Environmental sustainability of toxic arsenic ions removal from wastewater using electrodeionization
Saravanan A., Yaashikaa P.R., Senthil Kumar P., Karishma S., Thamarai P., Deivayanai V.C., Rangasamy G., Selvasembian R., Aminabhavi T.M.
Review, Separation and Purification Technology, 2023, DOI Link
View abstract ⏷
Removal of arsenic from wastewater has been crucial in recent days because of its high persistence and bioaccumulation causing serious health and environmental issues, listed in highly toxic pollutants. The review will cover broad perspectives of the electrodeionization (EDI) technique as a sustainable approach towards the wastewater detoxification by eliminating toxic arsenic. The electrodeionization employs hybrid electrodialysis/ion exchange method to eliminate arsenic ions from water before reusing processed water. The process utilizes anion/cation exchange resins that are persistently regenerated by an electric current, which significantly reduces the ions in water. Here, we will discuss module configuration, performance optimization and an overview of the EDI process and discuss the mechanism of ion separation. The applications and recent advances with respect to the removal/recovery of toxic arsenic using EDI to produce pure water are discussed. The future perspectives and sustainability aspects of EDI process for arsenic and other hazardous pollutant removal are critically evaluated with its potential applications. According to findings of this study, electrodeionization has the highest ion removal capacity of around 99 % when performed under low voltage range.
An overview on ZnO-based sonophotocatalytic mitigation of aqueous phase pollutants
Dhull P., Sudhaik A., Raizada P., Thakur S., Nguyen V.-H., Van Le Q., Kumar N., Parwaz Khan A.A., Marwani H.M., Selvasembian R., Singh P.
Article, Chemosphere, 2023, DOI Link
View abstract ⏷
Over the past several decades, the increase in industrialization provoked the discharge of harmful pollutants into the environment, affecting human beings and ecosystems. ZnO-based photocatalysts seem to be the most promising photocatalysts for treating harmful pollutants. However, fast charge carrier recombination, photo corrosion, and long reaction time are the significant factors that reduce the photoactivity of ZnO-based photocatalysts. In order to enhance the photoactivity of such photocatalysts, a combined process i.e., sonocatalysis + photocatalysis = sonophotocatalysis was used. Sonophotocatalysis is one of several different AOP methods that have recently drawn considerable interest, as it produces high reactive oxygen species (ROS) which helps in the oxidation of pollutants by acoustic cavitation. This combined technique enhanced the overall efficiency of the individual method by overcoming its limiting factors. The current review aims to present the theoretical and fundamental aspects of sonocatalysis and photocatalysis along with a detailed discussion on the benefits that can be obtained by the combined process i.e., US + UV (sonophotocatalysis). Also, we have provided a comparison of the excellent performance of ZnO to that of the other metal oxides. The purpose of this study is to discuss the literature concerning the potential applications of ZnO-based sonophotocatalysts for the degradation of pollutants i.e., dyes, antibiotics, pesticides, phenols, etc. That are carried out for future developments. The role of the produced ROS under light and ultrasound stimulation and the degradation mechanisms that are based on published literature are also discussed. In the end, future perspectives are suggested, that are helpful in the development of the sonophotocatalysis process for the remediation of wastewater containing various pollutants.
Pharmaceuticals in wastewater and their photocatalytic degradation using nano-enabled photocatalysts
Ruziwa D.T., Oluwalana A.E., Mupa M., Meili L., Selvasembian R., Nindi M.M., Sillanpaa M., Gwenzi W., Chaukura N.
Review, Journal of Water Process Engineering, 2023, DOI Link
View abstract ⏷
Pharmaceuticals in the concentration range of hundreds of ng/L to μg/L occur in wastewater and end up in surface water, groundwater and agricultural land where they cause various health risks. These pollutants are classified as emerging and cannot be efficiently removed by conventional wastewater treatment processes. The use of nano-enabled photocatalysts in the removal of pharmaceuticals in aquatic systems has recently received research attention owing to their enhanced properties and effectiveness. The industrial scale application of photocatalytic technology is still limited. A comprehensive review on the removal of pharmaceuticals from real wastewater using the photocatalysts is therefore necessary. This paper reviews literature on the occurrence, fate, and nano-sized photocatalytic removal strategies of pharmaceuticals from wastewater. Modifications of nano-enabled photocatalysts through doping, deposition on various supports, and introducing magnetic character to enhance their photocatalytic efficiency and recyclability were discussed. The synthetic routes of photocatalysts influence the physical and chemical properties which can either enhance or inhibit their effectiveness. The benefits of photocatalytic degradation include easy recycling as they exhibit excellent stability, and can be used for several cycles. Going forward, research should focus on: (1) elucidation of photodegradation mechanisms, (2) real wastewater treatment at industrial scale to remove multiple pharmaceutical compounds, (3) regeneration, and disposal particularly towards large scale application, (4) life cycle assessment of the photocatalysts from synthesis to application, (5) lowering the cost and improving photodegradation efficiency, and (6) investigating the toxicity of intermediates to the photocatalyst and the environment.
Enhanced adsorptive removal of hexavalent chromium in aqueous media using chitosan-modified biochar: Synthesis, sorption mechanism, and reusability
Perera H.M., Rajapaksha A.U., Liyanage S., Ekanayake A., Selvasembian R., Daverey A., Vithanage M.
Article, Environmental Research, 2023, DOI Link
View abstract ⏷
Hexavalent chromium (Cr(VI)) is deemed a priority contaminant owing to its carcinogenicity, teratogenicity, and mutagenicity towards flora and fauna. A novel Chitosan-modified Mimosa pigra biochar (CMPBC) was fabricated and the efficiency of Cr(VI) oxyanion removal in aqueous systems was compared with the pristine biochar. The instrumental characterization of X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FT-IR) confirmed the amino modification of MPBC when treated with chitosan. Characteristic features of the Cr(VI) sorptive process by CMPBC and MPBC were examined by performing batch sorption studies. Experimental data suggested that sorption is heavily dependent on pH and the highest adsorption occurred at pH 3.0. The maximum adsorption capacity of CMPBC was 14.6 ± 1.07 mg g−1. It was further noted that the removal efficiency of CMPBC (92%) was considerably greater than that of MPBC (75%) when the solution pH, biochar dose, and initial concentration of Cr(VI) are 3.0, 1.0 g L−1 and 5.0 mg L−1 respectively. The kinetic data were best interpreted by the power function model (R2 = 0.97) suggesting a homogenous chemisorption process. The isotherm data for the removal of Cr(VI) by CMPBC was inferred well by Redlich Peterson (R2 = 0.96) and Temkin (R2 = 0.96) isotherms. Results of sorption-desorption regeneration cycles indicated that the Cr(VI) uptake by CMPBC is not fully reversible. The coexistence of Cr(VI) and Cr(III) on CMPBC was confirmed through the XPS analysis. The electrostatic attractions between cationic surface functionalities and Cr(VI) oxyanions, the partial reductive transformation of Cr(VI) species to Cr(III), as well as complexation of Cr(III) onto CMPBC were identified as the possible mechanisms of mitigation of Cr(VI) by CMPBC. The results and outcomes of this research suggest the possibility of utilizing the CMPBC as an easily available, environmentally sustainable, and inexpensive sorbent to decontaminate Cr(VI) from aqueous media.
Bi-rich BixOyBrz-based photocatalysts for energy conversion and environmental remediation: A review
Chawla A., Sudhaik A., Sonu, Raizada P., Ahamad T., Le Q.V., Nguyen V.-H., Thakur S., Mishra A.K., Selvasembian R., Singh P.
Review, Coordination Chemistry Reviews, 2023, DOI Link
View abstract ⏷
Recently, BiOX-based (X = F, Cl, Br, I, etc.) photocatalysts have been discovered and used in many energy and environmental applications. However, inadequate reduction activities and positive conduction band minimum (CBM) potential are the main bottlenecks of BiOX. Therefore, a potential solution to addressing such constraints is to adopt a Bi-rich strategy with BiOX photocatalyst. The comprehensive features of Bi-rich BixOyBrz led us to select them over all other BiOX. These photocatalysts exhibit perfect band gap in the visible region ≅ 2.8 eV, account top portion of visible light (43–45%), and have rich atomic composition and layered crystal structure (providing large surface area for charge transfer), making them ideal photocatalysts. With their unique properties, the modified Bi-rich BixOyBrz is more favorable to addressing environmental and energy conversion concerns. However, fast charge recombination and more positive conduction band of some of the Bi-rich BixOyBrz reduce their photocatalytic activity. As a result, the current review offers an in-depth overview of numerous strategies for modifying Bi-rich BixOyBrz photocatalysts, such as employing co-catalysts, doping, heterojunction, microstructure regulation, etc. The detailed characteristics of Bi-rich BixOyBrz and their synthesis processes are also briefly presented in the proposed review paper. Also, various applications of Bi-rich BixOyBrz photocatalysts for pollutant degradation, hydrogen generation, solar fuel conversion, CO2 reduction, and nitrogen fixation have been presented with their proposed photocatalytic mechanism. Finally, following in-depth analysis and reasoned discussion, the article concludes with key findings and future research directions that provide new advancements in other rapidly evolving disciplines that can find application in the energy and environmental areas.
An overview on cellulose-supported photocatalytic materials for the efficient removal of toxic dyes
Malhotra M., Sudhaik A., Sonu, Raizada P., Ahamad T., Nguyen V.-H., Van Le Q., Selvasembian R., Mishra A.K., Singh P.
Article, Industrial Crops and Products, 2023, DOI Link
View abstract ⏷
Recently, the concept of green chemistry has emerged as a novel and efficient way for environmental remediation. Amongst several biomaterials, cellulose is the most widely utilized natural biopolymer and significant adsorbent due to its unique and exceptional characteristics such as biodegradability, biocompatibility, reproducibility, non-toxicity, cost-effectiveness, increased specific area, greater interaction between active sites and pollutants, and high adsorption capacity. On the other hand, photocatalysis, an advanced water purification technique accelerates chemical reactions in the presence of light. But, the photocatalysts are inherited with certain limitations like low surface area for adsorption, charge carriers’ recombination rate, etc. In this regard, the combination of cellulose with other photocatalysts typically results in adsorptional photocatalysis which improved porosity, surface area, and photocatalytic efficacy of photocatalysts. Cellulose serves as a support material and acts as an electron mediator that effectively enhanced charge carrier's migration ability and decreases their recombination rate. Hence, the current review mainly focuses on the incorporation of cellulose materials with various photocatalysts to enhance their photocatalytic efficiency. Also, the review briefly discussed the structural properties and various types of cellulose biomaterials as well as various types of harmful dyes with their hazardous effects. Additionally, the photocatalytic efficacy of various metal-oxides, metal-sulfides, metal-free photocatalysts, and cellulose-supported photocatalysts was explored with mechanistic insights toward the photodegradation of toxic dyes.
Separation of Mixtures of Rutin and Quercetin: Evaluating the Productivity of Preparative Chromatography
Vu T.D., Selvasembian R., Mutavdzin I., Horosanskaia E., Lorenz H., Seidel-Morgenstern A.
Article, Chemie-Ingenieur-Technik, 2023, DOI Link
View abstract ⏷
The flavonoid rutin is present in significant amounts in the flower buds of Sophora japonica L. It offers numerous desired pharmacological effects. Under certain extraction conditions quercetin is found as a hydrolysis product which needs to be separated from rutin. This paper describes the application of liquid chromatography to solve this task. Based on the determination of adsorption equilibrium constants and column efficiencies, the productivity of the separation process is estimated, and scale-up considerations are presented. A comparison with alternatively directly crystallizing rutin from raw extracts is also reported.
Recent advances in the adsorptive removal of 2,4-dichlorophenoxyacetic acid from water
Ighalo J.O., Ojukwu V.E., Umeh C.T., Aniagor C.O., Chinyelu C.E., Ajala O.J., Dulta K., Adeola A.O., Rangabhashiyam S.
Review, Journal of Water Process Engineering, 2023, DOI Link
View abstract ⏷
Numerous investigations have been conducted to address 2,4-D removal from water via adsorption approach. The present review offers insights into the underlying mechanisms, pinpoint gaps in the knowledge of the process, and offer a perspective for forthcoming inquiries. Notably, the highest adsorption capacity for 2,4-D reaches 556 mg/g, attributed to a metal-organic framework (MOF) based on porous chromium-benzenedicarboxylate. 2,4-D interactions with most adsorbents are usually by electrostatic interactions, hydrogen bonds, van der Waals forces, and π–π interaction. Isotherm modelling for 2,4-D uptake reveals either Langmuir or Freundlich as best-fit depending on whether uptake is monolayer or multilayer. The pseudo-second order kinetic equation effectively modelled the kinetics of uptake, highlighting that the rate of adsorption is contingent upon both the quantity of active sites and the concentration of 2,4-D within the aqueous phase. The thermodynamics modelling reveals that its adsorptive uptake is always spontaneous. Over a wide range of eluents, 2,4-D can be desorbed from the adsorbents back into the aqueous phase and the adsorbents are mostly reusable for over 5 cycles. Future work could explore the economic analysis and scalability of adsorption processes for the removal of 2,4-D.
An Integrated Approach for Electronic Waste Management—Overview of Sources of Generation, Toxicological Effects, Assessment, Governance, and Mitigation Approaches
Nandan A., Suresh A.C., Saole P., Jeevanasai S.A., Chandrasekaran R., Meili L., Wan Azelee N.I., Selvasembian R.
Review, Sustainability (Switzerland), 2023, DOI Link
View abstract ⏷
Electronic waste (e-waste) management has become a significant challenge in recent years due to the increasing consumption of electronic devices and their improper disposal. Effective e-waste management requires a comprehensive approach that considers the environmental, economic, and social impacts of e-waste. This comprehensive review provides a critical assessment of e-waste management procedures, encompassing the stages of collection, transportation, treatment, and disposal. Emphasising the significance of embracing sustainable approaches like reusing, repairing, and recycling, the review underscores their pivotal role in mitigating the adverse environmental and human health effects of e-waste. This review provides an overview of e-waste management concerns specifically in India from its collection to the end cycle including toxicological, environmental, and human impacts and a graphical analysis of current and future e-waste trends. It emphasises the need to effectively enforce regulations and establish extended producer responsibility (EPR) to promote sustainable e-waste management practices. Additionally, the review delves into the complexities surrounding e-waste management, such as insufficient infrastructure, resource and funding constraints, and a dearth of awareness among stakeholders. It strongly underscores the necessity for a concerted endeavour involving governments, industries, and communities to tackle these obstacles and advance the cause of efficient e-waste management practices. This paper is valuable to the scientific community as it offers a thorough assessment of e-waste management, focusing on environmental, economic, and social impacts. It emphasises sustainable practices and regulatory measures, providing actionable insights to address e-waste challenges. Overall, this review provides a comprehensive overview of e-waste management and highlights the importance of adopting sustainable practices to address the negative impacts of e-waste on the environment, human health, and the economy.
Mechanistic insights of nitrate removal by MgFe/layered double hydroxides prepared by different synthesis pathways
da Silva A.F., Duarte J.L.D.S., Georgin J., Franco D.S.P., Selvasembian R., Fernandes D.P., Meili L.
Article, Applied Surface Science Advances, 2023, DOI Link
View abstract ⏷
In this study, a layered MgFe/double hydroxide (MgFe/LDH) adsorbent for nitrate removal from simulated systems was developed and investigated. Three different synthesis methods were used: coprecipitation at constant pH (CC), conventional hydrothermal (CH), and pre-ultrasonic followed by conventional hydrothermal (UCH). The XRD results indicated that all synthesized samples presented the characteristic structure of LDHs. The analysis of FT-IR spectra before and after nitrate adsorption allowed the analysis of NO3−MgFe/LDH interaction in different adsorbents. Adsorption kinetics showed that all adsorbents reached equilibrium around 120 min, with the adsorption capacity being 6.970, 6.690, and 5.610 mg g−1 for the UCH, CH, and CC, respectively. Pseudo-second order and Langmuir models were the best models for describing the kinetics and isotherm data. The highest maximum adsorption capacity was reached at 330 K, with a value of 21.18 mg g−1 for the UHC. Thermodynamic analysis indicated that the adsorption of nitrate was exothermic and spontaneous despite the system. The results of this study suggest that the MgFe/LDH adsorbent synthesized by the UCH method with hydrothermal treatment presents a promising and efficient way of removing nitrate from polluted water, with potential application in the purification of water for human and environmental use.
Recent progress on the remediation of dyes in wastewater using cellulose-based adsorbents
Samuel M.S., John. J A., Ravikumar M., Raizada P., Wan Azelee N.I., Selvarajan E., Selvasembian R.
Article, Industrial Crops and Products, 2023, DOI Link
View abstract ⏷
The increasing rise of hazardous dye (toxic and carcinogenic) in wastewater produced by multiple industries continues to become major threats to human health and environment, providing a big problem for conventional water treatment facilities to tackle this issue. Based on their appearance and physical characteristics, dyes are classified into different categories and are used in many industries. The presence of these dyes in water effluents imposes negative impacts on humans, ecosystem, and the aquatic organisms. To overcome these problems, numerous physical, chemical, and bio-based treatment methods have been researched and reported with different level of removal efficiencies based on the limitations of each approach and experimental conditions. Featuring high performance in removal efficiency, simplicity of usage, economical, and high recyclability of the absorbents have made adsorption as one of the most effective dye remediation methods. The creation of excellent nanomaterials has sped up the revolution in most industries. Green nanomaterials sourced from plant are the most promising technology as the raw materials exist in abundance in addition to the renewable resources. Nanocellulose from plant biomass exhibits excellent characteristics of renewability, biocompatibility with large surface area and high strength. In recent years, interest in utilizing nanocellulose and its derivatives as potential green approach for the removal of wastewater pollutants has emerged drastically. The present review focuses on the cellulose-based adsorptions for dye remediations, characterization aspects, parametric influence, modelling, and mechanisms.
Sustainable valorization approaches on crustacean wastes for the extraction of chitin, bioactive compounds and their applications – A review
Azelee N.I.W., Dahiya D., Ayothiraman S., Noor N.M., Rasid Z.I.A., Ramli A.N.M., Ravindran B., Iwuchukwu F.U., Selvasembian R.
Article, International Journal of Biological Macromolecules, 2023, DOI Link
View abstract ⏷
The unscientific disposal of the most abundant crustacean wastes, especially those derived from marine sources, affects both the economy and the environment. Strategic waste collection and management is the need of the hour. Sustainable valorization approaches have played a crucial role in solving those issues as well as generating wealth from waste. The shellfishery wastes are rich in valuable bioactive compounds such as chitin, chitosan, minerals, carotenoids, lipids, and other amino acid derivatives. These value-added components possessed pleiotropic applications in different sectors viz., food, nutraceutical, cosmeceutical, agro-industrial, healthcare, and pharmaceutical sectors. The manuscript covers the recent status, scope of shellfishery management, and different bioactive compounds obtained from crustacean wastes. In addition, both sustainable and conventional routes of valorization approaches were discussed with their merits and demerits along with their combinations. The utilization of nano and microtechnology was also included in the discussion, as they have become prominent research areas in recent years. More importantly, the future perspectives of crustacean waste management and other potential valorization approaches that can be implemented on a large scale.
Hydrometallurgical processes for heavy metals recovery from industrial sludges
Gunarathne V., Rajapaksha A.U., Vithanage M., Alessi D.S., Selvasembian R., Naushad M., You S., Oleszczuk P., Ok Y.S.
Article, Critical Reviews in Environmental Science and Technology, 2022, DOI Link
View abstract ⏷
Hydrometallurgical approaches have been successfully employed for metal separation and recovery from various types of waste materials. Therefore, hydrometallurgy is a promising technology for metal recovery and the removal of potentially toxic heavy metals found in industrial sludge. However, a comprehensive review that focuses on the heavy metal recovery from industrial sludge using hydrometallurgical approaches has not been conducted in the recent past. The present review discusses the capacity of hydrometallurgical techniques in recovering heavy metals sourced from different types of industrial sludges, highlighting recent scientific findings. Hydrometallurgical approaches primarily consist of three process stages: metal dissolution, concentration and purification, and metal recovery. The chemical characteristics of industrial sludge, including the type, concentration and speciation of heavy metals, directly impact selection of the best recovery method. Solvent extraction, ion-exchange, and adsorption are the major techniques employed in concentration and purification, whereas electrodeposition and precipitation are the main methods used in metals recovery. Future research should focus on the development of more efficient and environmentally-friendly methods for metal dissolution from industrial sludges contaminated with multiple metals, while increasing selectivity and energy use efficiency in the concentration and purification, and recovery steps.
Utilization of avocado (Persea americana) adsorbents for the elimination of pollutants from water: a review
Ighalo J.O., Yao B., Zhou Y., Iwuozor K.O., Anastopoulos I., Aniagor C.O., Rangabhashiyam S.
Book chapter, Biomass-Derived Materials for Environmental Applications, 2022, DOI Link
View abstract ⏷
Biomass utilization as an adsorbent for water treatment is an important aspect of environmental protection efforts. It gives a two-pronged advantage of waste valorization and environmental pollution control. In this chapter, the research efforts on water pollutants removal using adsorbents prepared using avocado (Persea americana) biomass was reviewed. Chemical modification by wet impregnation of acids and/or salts is the most utilized techniques for the treatment/activation of avocado-based adsorbents. The avocado adsorbents with higher specific surface area were those that underwent thermochemical processing while the biosorbents had relatively lesser specific surface area. Avocado-based adsorbents were efficient for the removal of dyes, heavy metals, and other water pollutants. Equilibrium isotherm modeling revealed the Langmuir and Sips isotherms as best-fits in most cases while the pseudo-second order model was the best-fit kinetics model in most cases. Though there were no general observations from the thermodynamics analysis, the parameters dependent on the nature of the adsorbent and adsorbate materials. For future work, the review suggested that the lifecycle analysis of adsorbent production and utilization, and cost analysis be performed. It can be surmised that avocado bears great potential for utilization as an adsorbent for water pollution remediation.
Biogenic Synthesis of Nanoparticles and Its Application in Wastewater Treatment
Dhar S., Selvasembian R., Sharma R., Singh P., Mal C., Mishra A.K., Mal J.
Book chapter, Biotechnology for Environmental Protection, 2022, DOI Link
View abstract ⏷
Nanotechnology is a boon in the field of science as well as for all life forms in our blue planet. These nanoparticles have found tremendous application in various fields such as in environmental biotechnology, in agriculture as fertilizers, in the production of glass and alloys and in solar cells, photoconductors, nanomedicine, cosmetics, food industry, drug delivery, biosensors, etc. Nanoparticles can be formed chemically, but recent research has focussed mainly in the production of nanoparticles by green/biogenic synthesis, which is found to be eco-friendly. Production of biogenic nanoparticles is very economical, utilizes less energy and produces little or no toxic end/by-products, so this method can be used as an alternative to other approaches. This book chapter highlights the various approaches and microbiological sources (such as bacteria, fungi, actinomycete, algae and yeast) for nanoparticle production and how their biosorptive and catalytic properties are used in the removal and degradation of various types of pollutants from the environment.
Occurrence and ecological health risks of microplastics
Gwenzi W., Simbanegavi T.T., Mahdi H.I., Azelee N.I.W., Muisa-Zikali N., Rangabhashiyam S.
Book chapter, Emerging Contaminants in the Terrestrial-Aquatic-Atmosphere Continuum: Occurrence, Health Risks and Mitigation, 2022, DOI Link
View abstract ⏷
An increasing body of evidence exists on the occurrence of (micro)plastics in various environmental compartments including soils, aquatic systems, and as air-borne particulates. (Micro)plastics and their associated chemical additives pose potential environmental and ecological health risks. Information on the environmental and ecological health risks of microplastics remains scattered in several articles, while the few available reviews often focus on one environmental compartment such as soils or aquatic systems. Here, we applied the eco-hierarchical or ecosystem cascade framework to examine the evidence, and present a comprehensive synthesis of the environmental and ecological health risks of microplastics. First, the eco-hierarchical or ecosystem cascade framework and its principles are presented. Second, the impacts of microplastics and their chemical additives on the soil physico-chemical properties and ecological processes, including biogeochemical cycling are discussed. This is then followed by a discussion of the ecological impacts of microplastics on aquatic ecology, including behaviour, physiology, feeding habits, and growth-related parameters. Using the eco-hierarchical or ecosystem cascade framework, under-studied aspects of the ecological impacts of microplastics were identified. These include the impacts of microplastics and their chemical additives on: (1) trophic interactions, (2) ecosystem goods, services, and benefits, and (3) interactions of microplastics with other ecological health stressors such as legacy and emerging chemical and biological contaminants such as synthetic chemicals and antibiotic resistance. Lastly, future research directions including several knowledge gaps and the application of emerging research tools are presented.
Biosorption study of amaranth dye removal using Terminalia chebula shell, Peltophorum pterocarpum leaf and Psidium guajava bark
Malleswari P.V.N., Swetha S., Jegadeesan G.B., Rangabhashiyam S.
Article, International Journal of Phytoremediation, 2022, DOI Link
View abstract ⏷
Amaranth dye (AD) is trisodium (4E)-3-oxo-4-[(4-sulfonato-1- naphthyl) hydrazono] naphthalene-2, 7-disulfonate and anionic in nature. In the present investigation, waste biomasses such as Terminalia chebula shell (TCS), Peltophorum pterocarpum leaf (PPL) and Psidium guajava bark (PGB) are explored as biosorbents for the first time toward the removal of AD from aqueous solution in a batch method. Influence of biosorption parameters such as pH, initial concentration of AD, biosorbents (TCS, PPL, PGB) dosage, temperature and contact time was studied. Biosorption equilibrium data was analyzed using two parameter isotherms. The kinetics of the biosorption process was analyzed using different models to understand the rate-determining step. The results of the biosorption experiment and modeling investigation illustrated that the pseudo-second-order rate equation fits the experimental data and further the experimental results showed Langmuir isotherm fitted well the biosorption equilibrium data. TCS showed more efficiency toward the removal of AD than PPL and PGB. The value of enthalpy for TCS is 1.527 kJ/mol suggests that the AD removal process is endothermic. The positive value of entropy is 6.429 J/mol K indicates that the particle is randomly disordered and negative values of standard Gibbs free energy (ΔG°) suggested that the biosorption process is spontaneous.Novelty statement Biomasses of Terminalia chebula shell (TCS), Peltophorum pterocarpum leaf (PPL) and Psidium guajava bark (PGB) reported as first time explored biosorbent for amaranth dye (AD) removal from aqueous solution. Optimal biosorption parameter for AD removal determined. Experimental data examined using isotherm, kinetic and thermodynamic analysis.
Lanthanum hydroxide engineered sewage sludge biochar for efficient phosphate elimination: Mechanism interpretation using physical modelling
Elkhlifi Z., Sellaoui L., Zhao M., Ifthikar J., Jawad A., Shahib I.I., Sijilmassi B., Lahori A.H., Selvasembian R., Meili L., Gendy E.A., Chen Z.
Article, Science of the Total Environment, 2022, DOI Link
View abstract ⏷
In the present study, lanthanum hydroxide (La OH)-engineered sewage sludge biochar (La-SSBC) was utilized for efficient phosphate elimination from an aqueous medium. A high adsorption capacity of 312.55 mg P/g was achieved using La-SSBC at 20 °C, which was an excellent adsorbent performance in comparison to other biochar-based adsorbents. Additionally, the performance of La-SSBC was stable even at wider range of pH level, the existence of abundant active anions, and recycling experiments. Statistical physics modeling with the fitting method based on the Levenberg–Marquardt iterating algorithm, as well as various chemical characterizations, suggested the unique double-layered mechanism of phosphate capturing: one functional group of La-SSBC adsorbent describing a prone direction of the PO4 ions on the stabilize surface in a multi-ionic process, forming the first layer adsorption. Additionally, SSBC played an important role by releasing positively charged cations in solution, overcoming the electronic repulsion to form a second layer, and achieving excellent adsorption capacity. The calculation of multiple physicochemical parameters including adsorption energy further evidenced the process. This two-layered mechanism sheds light on the complex interaction between phosphate and biochar. Moreover, the management of sewage sludge associated with the requirement of cost-effectively and environmentally acceptable mode. Therefore, the present investigation demonstrated an efficient approach of the simultaneous sewage sludge utilization and phosphate removal.
Biotechnology for Environmental Protection
Selvasembian R., van Hullebusch E.D., Mal J.
Book, Biotechnology for Environmental Protection, 2022, DOI Link
View abstract ⏷
This book covers broader application of biotechnology for the protection of environment through different bioremediation and biodegradation techniques developed for removal of environmental contaminants including the recently discovered contaminants. The book offers a comprehensive overview of environmental pollutants including their fate, behavior, environmental and associated health risks. It is useful reading material for postgraduate and graduate students of environmental biotechnology, environmental microbiology and ecology. Young researchers also find the chapters useful understanding the latest developments.
Sewage sludge-derived biochar for the adsorptive removal of wastewater pollutants: A critical review
Rangabhashiyam S., Lins P.V.D.S., Oliveira L.M.T.D.M., Sepulveda P., Ighalo J.O., Rajapaksha A.U., Meili L.
Review, Environmental Pollution, 2022, DOI Link
View abstract ⏷
The production of biochar from sewage sludge pyrolysis is a promising approach to transform the waste resultant from wastewater treatment plants (WWTPs) to a potential adsorbent. The current review provides an up-to-date review regarding important aspects of sewage sludge pyrolysis, highlighting the process that results major solid fraction (biochar), as high-value product. Further, the physio-chemical characteristics of sewage-sludge derived biochar such as the elemental composition, specific surface area, pore size and volume, the functional groups, surface morphology and heavy metal content are discussed. Recent progress on adsorption of metals, emerging pollutants, dyes, nutrients and oil are discussed and the results are examined. The sewage sludge-derived biochar is a promising material that can make significant contributions on pollutants removal from water by adsorption and additional benefit of the management of huge volume of sewage. Considering all these aspects, this field of research still needs more attention from the researchers in the direction of the technological features and sustainability aspects.
Zeolitic Imidazolate Frameworks (ZIFs) for aqueous phase adsorption – A review
Ighalo J.O., Rangabhashiyam S., Adeyanju C.A., Ogunniyi S., Adeniyi A.G., Igwegbe C.A.
Review, Journal of Industrial and Engineering Chemistry, 2022, DOI Link
View abstract ⏷
Zeolitic Imidazolate Frameworks (ZIFs) represents a subclass of the metal-organic frameworks (MOFs), composed mainly of tetrahedrally coordinated transition metals. The aim of this review was to evaluate the experimental findings on the adsorption of different aqueous pollutants using ZIFs. ZIF adsorption mechanism was electrostatic attraction, π-π interaction and complexation though others were observed based on pollutant type and nature of the solution chemistry. Thermodynamic modelling revealed that ZIF adsorption is usually spontaneous and endothermic. The adsorbent can be re-used for 3–4 cycles with >70% retention of uptake performance. NaOH, methanol and ethanol were observed to be the more suitable and effective eluents for desorption of adsorbate from ZIF. The nature of the adsorbate and the type of uptake mechanism are the two key considerations in competitive adsorption systems. When the uptake mechanism of the main adsorbate species is different from that of the competing species, then the adsorption process is unaffected. Investigations on adsorbent disposal, targeted modification, functionalisation, emerging contaminants removal, column adsorption studies and molecular modelling would be needed to fill in gaps in knowledge in ZIF related studies.
Recent progress in microbial fuel cells for industrial effluent treatment and energy generation: Fundamentals to scale-up application and challenges
Selvasembian R., Mal J., Rani R., Sinha R., Agrahari R., Joshua I., Santhiagu A., Pradhan N.
Review, Bioresource Technology, 2022, DOI Link
View abstract ⏷
Microbial fuel cells (MFCs) technology have the potential to decarbonize electricity generation and offer an eco-friendly route for treating a wide range of industrial effluents from power generation, petrochemical, tannery, brewery, dairy, textile, pulp/paper industries, and agro-industries. Despite successful laboratory-scale studies, several obstacles limit the MFC technology for real-world applications. This review article aimed to discuss the most recent state-of-the-art information on MFC architecture, design, components, electrode materials, and anodic exoelectrogens to enhance MFC performance and reduce cost. In addition, the article comprehensively reviewed the industrial effluent characteristics, integrating conventional technologies with MFCs for advanced resource recycling with a particular focus on the simultaneous bioelectricity generation and treatment of various industrial effluents. Finally, the article discussed the challenges, opportunities, and future perspectives for the large-scale applications of MFCs for sustainable industrial effluent management and energy recovery.
Treatment technologies for bakers’ yeast production wastewater
Igwegbe C.A., Obiora-Okafo I.A., Iwuozor K.O., Ghosh S., Kurniawan S.B., Rangabhashiyam S., Kanaoujiya R., Ighalo J.O.
Review, Environmental Science and Pollution Research, 2022, DOI Link
View abstract ⏷
Researchers in recent years have utilized a broad spectrum of treatment technologies in treating bakers’ yeast production wastewater. This paper aims to review the treatment technologies for the wastewater, compare the process technologies, discuss recent innovations, and propose future perspectives in the research area. The review observed that nanofiltration was the most effective membrane process for the treatment of the effluent (at >95% pollutant rejection). Other separation processes like adsorption and distillation had technical challenges of desorption, a poor fit for high pollutant load and cost limitations. Chemical treatment processes have varying levels of success but they are expensive and produce toxic sludge. Sludge production would be a hurdle when product recovery and reuse are targeted. It is difficult to make an outright choice of the best process for treating the effluent because each has its merits and demerits and an appropriate choice can be made when all factors are duly considered. The process intensification of the industrial-scale production of the bakers’ yeast process will be a very direct approach, where the process optimisation, zero effluent discharge, and enhanced recovery of value-added product from the waste streams are important approaches that need to be taken into account.
A systematic review on adsorptive removal of hexavalent chromium from aqueous solutions: Recent advances
Rajapaksha A.U., Selvasembian R., Ashiq A., Gunarathne V., Ekanayake A., Perera V.O., Wijesekera H., Mia S., Ahmad M., Vithanage M., Ok Y.S.
Review, Science of the Total Environment, 2022, DOI Link
View abstract ⏷
The contamination of natural resources by hexavalent chromium (Cr(VI)) originating from natural and anthropogenic activities is a serious environmental concern. Although many articles on chromium remediation have been published, a comprehensive understanding of the mechanisms involved in remediation with different sorbents is not yet available. In this systematic review, the performance and applicability of several adsorptive materials for Cr(VI) removal from aqueous media are discussed, along with a detailed analysis of the mechanisms involved. Statistical analysis is applied to compare the efficacies of different adsorbents, while a similar approach is used to determine the effects of sorbent properties and experimental conditions on the adsorption capacity. A detailed analysis of the factors involved in fixed-bed column studies is also presented. A suitable desorption approach to the regeneration of the spent adsorbent and its adsorption performance in reuse is also examined. Among the different sorbents, nanoparticles and mineral-doped biochar were found to be the most effective sorbents, while the adsorption was higher at low pH (~4.0) than that at intermediate pH (6–8). Contrary to our expectation, adsorption was high for sorbents with low specific surface areas, suggesting that the adsorption of Cr(VI) is largely influenced by the chemical properties of the sorbents. The optimum adsorption in fixed-bed column systems is obtained at a lower Cr(VI) ion concentration, a lower influent flow rate, and a higher bed height. Since most of the studies reviewed herein were merely experimental and utilized ideal conditions with the presence of a single contaminant, i.e. Cr(VI) in water, further studies on adsorption dynamics with the presence of other interfering ions are suggested. This review is promising for the further development of Cr(VI) removal strategies and closes the research gaps pertaining to their challenges.
Emerging new-generation covalent organic frameworks composites as green catalysts: design, synthesis and solar to fuel production
Patial S., Raizada P., Aslam Parwaz Khan A., Singh A., Van Le Q., Huy Nguyen V., Selvasembian R., Mustansar Hussain C., Singh P.
Review, Chemical Engineering Journal, 2022, DOI Link
View abstract ⏷
Due to structural versatility, permanent porosity, low mass densities, and exceptional stability, covalent-organic frameworks (COFs) have received great interest in green catalysis. The fruitful combination of COFs with carbonaceous materials, polymer, metal nanoparticles, and porous polymer networks results in sustainable COFs-based composites. The synthetic routes like functionalization with knots and linker coating and encapsulation methods are discussed due to affordability, non-flammable, and environment-friendly nature. The review offers the recent advances in variant categories of green COFs composites, synthesis routes, and their applications as sustainable catalyst. Mainly, we focused on the green reaction parameters, including chemical reactions under solvent-free or mild conditions, which endorses their wide-range applicability at both industrial and scientific stages. Lastly, an outlook on the ongoing challenges and prospects for the future advancement of COFs composites are presented.
COVID-19 drugs in aquatic systems: a review
Gwenzi W., Selvasembian R., Offiong N.-A.O., Mahmoud A.E.D., Sanganyado E., Mal J.
Review, Environmental Chemistry Letters, 2022, DOI Link
View abstract ⏷
The outbreak of the human coronavirus disease 2019 (COVID-19) has induced an unprecedented increase in the use of several old and repurposed therapeutic drugs such as veterinary medicines, e.g. ivermectin, nonsteroidal anti-inflammatory drugs, protein and peptide therapeutics, disease-modifying anti-rheumatic drugs and antimalarial drugs, antiretrovirals, analgesics, and supporting agents, e.g. azithromycin and corticosteroids. Excretion of drugs and their metabolites in stools and urine release these drugs into wastewater, and ultimately into surface waters and groundwater systems. Here, we review the sources, behaviour, environmental fate, risks, and remediation of those drugs. We discuss drug transformation in aquatic environments and in wastewater treatment systems. Degradation mechanisms and metabolite toxicity are poorly known. Potential risks include endocrine disruption, acute and chronic toxicity, disruption of ecosystem functions and trophic interactions in aquatic organisms, and the emergence of antimicrobial resistance.
Current perspective in metal oxide based photocatalysts for virus disinfection: A review
Soni V., Khosla A., Singh P., Nguyen V.-H., Le Q.V., Selvasembian R., Hussain C.M., Thakur S., Raizada P.
Review, Journal of Environmental Management, 2022, DOI Link
View abstract ⏷
Nanotechnology holds huge potential for the prevention of various viral outbreaks that have increased at a disquieting rate over the past decades. Metal oxide nanomaterials with oxidative capability are the effective materials that provide platforms as well as tools for the well understanding of the mechanism, its detection, and treatment of various viral diseases like measles, influenza, herpes, ebola, current COVID-19 etc. In this inclusive review, we survey various previous research articles on different notable photoactive transition metal oxides that possess enough potential to act as antiviral agents for the deactivation of harmful viruses. We investigated and highlighted the plausible photocatalytic oxidative mechanism of photoactive transition metal oxides in degrading viral coatings, genomic RNA using suitable free radical generation. The key finding of the present review article including the discovery of a vision on the suitable photocatalytic transition metal oxides that have been proven to be excellent against harmful viruses and consequently combatting deadly CoV-2 in the environment. This review intends to provide conclusive remarks and a realistic outlook on other advanced photocatalytic metal oxides as a potential solution in battling other similar upcoming pandemics.
Waste tire particles as efficient materials towards hexavalent chromium removal: Characterisation, adsorption behaviour, equilibrium, and kinetic modelling
Sivaraman S., Michael Anbuselvan N., Venkatachalam P., Ramiah Shanmugam S., Selvasembian R.
Article, Chemosphere, 2022, DOI Link
View abstract ⏷
The growing demand for vehicles is increasing every year, and this paves the way for the environmental problem for the generation of the waste tire (WT) and associated disposal after their end life. On the other direction, effluent from tannery and electroplating industries contented with a higher concentration of chromium, which is a toxic pollutant, induces mutation effects. In this work, the approach of reutilization of waste tires as adsorbent is reported towards the sequestrations of hexavalent chromium (Cr(VI)) from the simulated system. The waste tire sample is activated using orthophosphoric acid (H3PO4) and utilized for adsorption studies. Adsorption studies are performed with native tire sample (NTP) and activated tire sample (ATP). About 96.5% of Cr(VI) adsorption efficiency was attained using ATP and at the optimal adsorption solution pH 2.0. The adsorbent performed relatively well in wide a range of initial solution pH tested in the present research. The experimental data analysis of Cr(VI) adsorption onto NTP and ATP revealed the best fit with the kinetic model of pseudo-second-order. Further, the equilibrium data were analysed using two-parameter isotherms, relatively the Langmuir isotherm best represented in both NTP and ATP. ATP demonstrated with higher Cr(VI) removal performance with an adsorption capacity of 102.90 mg/g, according to the Langmuir model. The proposed idea of utilizing waste tire particles as adsorbents in the treatment of Cr(VI) contaminated water offers valuable guidance towards further investigations in the directions of dynamic adsorption and effluent treatment.
Magnetic biohybrid chitosan-ethylene glycol diglycidyl ether/magnesium oxide/Fe3O4 nanocomposite for textile dye removal: Box–Behnken design optimization and mechanism study
Jawad A.H., Abdulhameed A.S., Selvasembian R., ALOthman Z.A., Wilson L.D.
Article, Journal of Polymer Research, 2022, DOI Link
View abstract ⏷
In this research work, a hybrid organic–inorganic magnetic nanocomposite of magnetic chitosan-ethylene glycol diglycidyl ether/magnesium oxide (CS-EGDE/MgO/Fe3O4) was prepared as a bioadsorbent material for dye wastewater treatment (reactive blue 19, RB 19). A response surface methodology (RSM) was adopted for the design of 29 experiments to investigate the effect of four factors [A: CS-EGDE/MgO/Fe3O4 dose (0.02–0.1 g), B: pH (4–10), C: temperature (30–60 °C), and time D: (20–80 min)] related to the adsorption of RB 19. The Freundlich adsorption isotherm and the pseudo-second-order kinetics model favourably describe the adsorption of RB 19 by CS-EGDE/MgO/Fe3O4. The CS-EGDE/MgO/Fe3O4 nanocomposite showed a maximum absorption capacity of 133.8 mg/g with the RB 19 dye at 45 °C. The adsorption mechanism for CS-EGDE/MgO/Fe3O4-RB 19 dye system involves electrostatic attraction, H- bonding, n-π interaction, and Yoshida H-bonding. This study supports that the nanocomposite system is an efficient bioadsorbent, which can be deployed for effective decontamination of water that contains acidic dye species.
Recent progress in emerging BiPO4-based photocatalysts: Synthesis, properties, modification strategies, and photocatalytic applications
Kumar R., Raizada P., Khan A.A.P., Nguyen V.-H., Van Le Q., Ghotekar S., Selvasembian R., Gandhi V., Singh A., Singh P.
Review, Journal of Materials Science and Technology, 2022, DOI Link
View abstract ⏷
In this perspective, we have highlighted the current literature and explained the synthesis, structure, morphology, modification strategies, and photocatalytic applications of emerging BiPO4-based photocatalysts. Since BiPO4 is a large bandgap photocatalyst, it uses UV light for the excitation of electrons, and also, the recombination of charge carriers is an issue in BiPO4. Various novel modification strategies of BiPO4 photocatalysts viz. defect modifications, heterojunction formation, phase-junctions, surface plasmon resonance, Schottky junction have been successfully proposed and highlighted. These modifications enhance the light absorption and inhibit the recombination of charge carriers BiPO4 photocatalyst. Finally, future aspects for further research on BiPO4-based photocatalysts are also explored. It expects that BiPO4-based photocatalysts represent a promising strategy for developing practical photocatalysts for energy and environmental remediation applications.
Assessment of methane enrichment efficacy of pre-disintegrated water hyacinth biomass using sonic wave assisted biosurfactant
Sethupathy A., Sobana Piriya P., Ranjith Kumar R., Shanthi M., Rangabhashiyam S., Arun C., Vasanth Ragavan K.
Article, Fuel, 2022, DOI Link
View abstract ⏷
In this study, sonic wave coupled Iturin A with alkaline pH mediated pre-disintegration was executed to attain enhanced biocellular substance release and upsurge the amenability of water hyacinth biomass (WHBI) towards bio-methanation. During pre-disintegration of WHBI sample, sonic wave coupled Iturin A with alkaline pH 11 necessitated less specific energy of 12110 kJ/kg TS for attaining 30 % of biomass lysis rate when compared to sonic wave coupled Iturin A method (specific energy: 21192 kJ/kg TS, biomass lysis rate: 22.7 %) and sole sonic wave method (specific energy: 35321 kJ/kg TS, biomass lysis rate:15.7 %). Then, pre-disintegrated WHBI samples were subjected to bio-methanation in which sonic wave coupled Iturin A with alkaline pH method attained higher biomethane production value (69 L/kg COD) than sonic wave coupled Iturin A method (52 L/kg COD), sonic wave method (41 L/kg COD), Iturin A method (35 L/kg COD) and control (11 L/kg COD). Further, the cost evaluation of pre-disintegration methods was proceeded in which sonic wave coupled Iturin A with alkaline pH method achieved net profit of 13.4 $ per ton of WHBI sample.
Current status of hematite (α-Fe2O3) based Z-scheme photocatalytic systems for environmental and energy applications
Kumar Y., Kumar R., Raizada P., Khan A.A.P., Singh A., Le Q.V., Nguyen V.-H., Selvasembian R., Thakur S., Singh P.
Article, Journal of Environmental Chemical Engineering, 2022, DOI Link
View abstract ⏷
Can Fe2O3 be useful for photocatalytic and subsequently for environmentally beneficial reactions? This question perturbed the researchers for many years. Keeping in view the weak electronic transitions in the visible region, it was considered that α-Fe2O3 is not fit for photocatalytic applications. However, crystalline iron oxide in the form of hematite, because of its abundance, cost, and features such as suitable band gap for visible light absorption, stability, biocompatibility, attracted researchers to tune it for photochemical applications. This review has discussed the correlation of structure, electronic and optical properties that directly affect its ability to act as a photocatalyst. Various challenges affect the performance for practical use in photocatalytic applications. In the next section, the application of α-Fe2O3 as a single photocatalyst and its limitation, which discourage its use, has been highlighted. Various strategies have been adopted to tune its properties, but recent thrust to use as a component in fabricating Z-scheme and dual Z-scheme, which enhance the redox ability of α-Fe2O3, has been reviewed. Finally, we presented the conclusion with a summary and some stimulating future perspectives.
Potential of graphene based photocatalyst for antiviral activity with emphasis on COVID-19: A review
Patial S., Kumar A., Raizada P., Le Q.V., Nguyen V.-H., Selvasembian R., Singh P., Thakur S., Hussain C.M.
Article, Journal of Environmental Chemical Engineering, 2022, DOI Link
View abstract ⏷
Coronavirus disease-2019 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been one of the most challenging worldwide epidemics of recent times. Semiconducting materials (photocatalysts) could prove effectual solar-light-driven technology on account of variant reactive oxidative species (ROS), including superoxide (•O2-) and hydroxyl (•OH) radicals either by degradation of proteins, DNA, RNA, or preventing cell development by terminating cellular membrane. Graphene-based materials have been exquisitely explored for antiviral applications due to their extraordinary physicochemical features including large specific surface area, robust mechanical strength, tunable structural features, and high electrical conductivity. Considering that, the present study highlights a perspective on the potentials of graphene based materials for photocatalytic antiviral activity. The interaction of virus with the surface of graphene based nanomaterials and the consequent physical, as well as ROS induced inactivation process, has been highlighted and discussed. It is highly anticipated that the present review article emphasizing mechanistic antiviral insights could accelerate further research in this field.
Recent Advances on the Aqueous Phase Adsorption of Carbamazepine
Adeyanju C.A., Ogunniyi S., Selvasembian R., Oniye M.M., Ajala O.J., Adeniyi A.G., Igwegbe C.A., Ighalo J.O.
Review, ChemBioEng Reviews, 2022, DOI Link
View abstract ⏷
Carbamazepine (CBZ) is a pharmaceutical compound used in medical practice. Due to the ecotoxicological risk of its presence in the aqueous environment, researchers have been investigating its removal by adsorption technique. The aim of this study is to review the works done on the removal of CBZ from water by adsorption. Carbon-based materials were the best types of adsorbent for CBZ uptake (> 200 mg g−1). Molecularly imprinted polymer (MIP) and carbon nanotubes (CNTs) showed especially good adsorption capacities. The key mechanisms of CBZ adsorption were π-π interaction, electrostatic interactions, hydrogen-bonding and hydrophobic interactions. Classical equilibrium isotherm models like Langmuir and Freundlich were always best-fits and kinetics modelling was best-fit to the pseudo-second order model. The thermodynamics modelling of CBZ adsorption showed it was spontaneous and endothermic for most adsorbents. Methanol and acetone were especially effective for the desorption of CBZ from adsorbents and can achieve > 90 % removal even after 4–5 cycles. CBZ competes favorably in adsorption systems with other pharmaceutical species due to the advantages of the hydrophobic effect and molecular size.
Process Optimization and Adsorptive Mechanism for Reactive Blue 19 Dye by Magnetic Crosslinked Chitosan/MgO/Fe3O4 Biocomposite
Jawad A.H., Rangabhashiyam S., Abdulhameed A.S., Syed-Hassan S.S.A., ALOthman Z.A., Wilson L.D.
Article, Journal of Polymers and the Environment, 2022, DOI Link
View abstract ⏷
A new biocomposite cross-linked glutaraldehyde-chitosan/MgO/Fe3O4 (CTS-GL/MgO/Fe3O4) adsorbent with magneto-responsiveness was prepared and applied for the removal of reactive blue 19 (RB-19), a synthetic textile dye. The prepared CTS-GL/MgO/Fe3O4 was structurally characterized using spectroscopic (XRD, FTIR, SEM–EDX), and its physicochemical properties were evaluated using potentiometry and pHpzc analyses. The influence of various adsorption parameters (A: CTS-GL/MgO/Fe3O4 dosage; B: initial solution pH; C: process temperature; and D: contact time) on the removal efficiency of RB-19 was statistically optimized using Box-Behnken design (BBD). The analysis of variance (ANOVA) indicates the presence of five significant statistical interactions between the adsorption parameters, as follows: AB, AC, AD, BC, and BD. The equilibrium dye uptake by the Freundlich isotherm model indicates heterogeneous adsorption, while the kinetics of adsorption was well-described by the pseudo-second-order model. The maximum adsorption capacity of CTS-GL/MgO/Fe3O4 towards RB-19 was 193.2 mg/g at 45 °C. This work highlights the development of a recoverable magnetic biocomposite adsorbent with favourable adsorption capacity towards a model textile dye with good separation ability by using an external magnetic field. Moreover, separation of the magnetic adsorbents from the treated solution is easy and convenient apply to continuous flow systems, which is highly preferred for industrial applications.
Highly sustainable cascade pretreatment of low-pressure steam heating and organic acid on pineapple waste biomass for efficient delignification
Nordin N., Md Illias R., Manas N.H.A., Ramli A.N.M., Selvasembian R., Azelee N.I.W., Rajagopal R., Thirupathi A., Chang S.W., Ravindran B.
Article, Fuel, 2022, DOI Link
View abstract ⏷
Cascade pretreatment of low-pressure steam heating (LPSH) and maleic acid (MA) on pineapple waste (PW) biomass aims to improve delignification, increase enzyme accessibility to carbohydrate in the feedstock while reducing inhibitor by-products. The best conditions for LPSH pretreatment were determined using one-factor-at-a-time (OFAT) while the conditions of MA pretreatment (temperature, acid concentration and time) were optimized by Box-Behnken design. A total of 68% (w/w) delignification with 79.5% (w/w) hemicellulose removal were achieved while 77.6% (w/w) cellulose was retained in the solid residue after the cascade pretreatment. No 5-hydroxylmethyl furfural (5-HMF) and acceptable furfural (1.8 g/L) were detected in the hydrolysate by high performance liquid chromatography analysis, with negligible amount of phenolic compounds (0.01 g/L). Compared to the pretreatment with combined LPSH and conventional sulphuric acid pretreatment (H2SO4), the pretreated PW produced 3.6 g/L of furfural and 0.4 g/L of HMF at similar optimized conditions. The pretreated PW were further characterized by scanning electron microscopy and Fourier transform infrared spectroscopy to analyze structural morphology and functional group changes. The pooled solid and liquid hydrolysate fractions generated from the LPSH and MA cascade pretreatment and subsequent enzyme hydrolysis has successfully generated 356.32 mg/g glucose and 156.91 mg/g xylose. The optimized cascade pretreatments provide up to 54.79% of glucose yield and 69.23% of xylose yield. Furthermore, 67.87% reduction of lignin content from the cascade pretreatment can substantially enhance the glucose yield up to 95.76% and xylose yield up to 99.07% during enzymatic hydrolysis using the mixture of cellulase and hemicellulase.
Recent advances in hydrochar application for the adsorptive removal of wastewater pollutants
Ighalo J.O., Rangabhashiyam S., Dulta K., Umeh C.T., Iwuozor K.O., Aniagor C.O., Eshiemogie S.O., Iwuchukwu F.U., Igwegbe C.A.
Article, Chemical Engineering Research and Design, 2022, DOI Link
View abstract ⏷
Water pollution is one of the major environmental challenges in contemporary times. Biochar from hydrothermal processes (known as hydrochars) has been explored as adsorbents for the removal of pollutants from wastewater. Hydrochars are a special class of biochar that is obtained from hydrothermal processes such as hydrothermal carbonisation (HTC) and hydrothermal liquefaction (HTL). Because of its good pore volume, surface area, high efficiency, and regeneration ability, hydrochar is an appealing choice for the remediation of a wide range of contaminants. This review aimed to focus the uniqueness of hydrochar properties and evaluate their performance on the adsorption of different pollutants from wastewater. It was observed that hydrochars can be effectively applied to a wide variety of pollutants including heavy metals, dyes, Pharmaceutically Active Compounds (PhACs), Endocrine Disruption Chemicals (EDCs), nitrates, phosphates and sulphate. The utilisation of hydrochar in water treatment solves constraints such as lack of regeneration, environmental friendliness, commercial feasibility, and disposal, handling or management concerns.
Biochemical and Physical Characterization of Immobilized Candida rugosa Lipase on Metal Oxide Hybrid Support
Ramlee N.N., Md Illias R., A. Rahman R., Toemen S., Selvasembian R., Ahmad R.A., Abdul Manas N.H., Wan Azelee N.I.
Article, Catalysts, 2022, DOI Link
View abstract ⏷
Enzyme immobilization on inorganic materials is gaining more attention with the potential characteristics of high-surface-area-to-volume ratios, increasing the efficiency of enzyme loading on the support. Metal oxide hybrid support was prepared by a wetness impregnation of five metal precursors, including CaO, CuO, MgO, NiO, and ZnO, on Al2O3 and used as a support for the immobilization of Candida rugosa lipase (CRL) by adsorption. Maximum activity recovery (70.6%) and immobilization efficiency (63.2%) were obtained after optimization of five parameters using response surface methodology (RSM) by Box–Behnken design (BBD). The biochemical properties of immobilized CRL showed high thermostability up to 70 °C and a wide range in pH stability (pH 4–10). TGA-DTA and FTIR analysis were conducted, verifying thermo-decomposition of lipase and the presence of an amide bond. FESEM-EDX showed the homogeneous distribution and high dispersion of magnesium and CRL on MgO-Al2O3, while a nitrogen adsorption–desorption study confirmed MgO-Al2O3 as a mesoporous material. CRL/MgO-Al2O3 can be reused for up to 12 cycles and it demonstrated high tolerance in solvents (ethanol, isopropanol, methanol, and tert-butanol) compared to free CRL.
Regeneration of dye-saturated activated carbon through advanced oxidative processes: A review
Santos D.H.D.S., Xiao Y., Chaukura N., Hill J.M., Selvasembian R., Zanta C.L.P.S., Meili L.
Review, Heliyon, 2022, DOI Link
View abstract ⏷
Activated carbon (AC) is a porous carbon-rich material that is widely used to remove pollutants, such as synthetic dyes, from contaminated water. Although quite efficient, the use of this technology is limited to the ability of the AC to be regenerated and/or reused. Conventional regeneration procedures are inefficient, requiring the development and/or implementation of new approaches. Advanced Oxidative Processes (AOP) have unique properties that result in high efficiency in wastewater treatment. The use of these technologies in the regeneration of AC has gained considerable prominence due to the ability to remove organic pollutants concentrated in the AC. During this process, the oxidizing species produced interact with the substrates adsorbed on the AC, in a non-selective way, mineralizing them and/or reducing their recalcitrance. Although widely used in wastewater treatment, few reviews focus on the use of AOP as AC regeneration technology, causing an insufficient exchange of information and ideas for strategic development in this area. Therefore, in this review, the authors present an overview of the use of some AOP (Photolysis, Peroxidation, Fenton reaction and Advanced electrochemical oxidative processes) when applied in regeneration of dye-saturated AC, including the mechanisms involved in the different processes, the general aspects that affect individual processes and the different methods established to quantify the effectiveness of regeneration.
Layered Double Hydroxides as Rising-Star Adsorbents for Water Purification: A Brief Discussion
Gama B.M.V.D., Selvasembian R., Giannakoudakis D.A., Triantafyllidis K.S., McKay G., Meili L.
Article, Molecules, 2022, DOI Link
View abstract ⏷
Within the frame of this article, briefly but comprehensively, we present the existing knowledge, perspectives, and challenges for the utilization of Layered Double Hydroxides (LDHs) as adsorbents against a plethora of pollutants in aquatic matrixes. The use of LDHs as adsorbents was established by considering their significant physicochemical features, including their textural, structural, morphological, and chemical composition, as well as their method of synthesis, followed by their advantages and disadvantages as remediation media. The utilization of LDHs towards the adsorptive removal of dyes, metals, oxyanions, and emerging pollutants is critically reviewed, while all the reported kinds of interactions that gather the removal are collectively presented. Finally, future perspectives on the topic are discussed. It is expected that this discussion will encourage researchers in the area to seek new ideas for the design, development, and applications of novel LDHs-based nanomaterials as selective adsorbents, and hence to further explore the potential of their utilization also for analytic approaches to detect and monitor various pollutants.
Amino-functionalized biochars for the detoxification and removal of hexavalent chromium in aqueous media
Ekanayake A., Rajapaksha A.U., Selvasembian R., Vithanage M.
Article, Environmental Research, 2022, DOI Link
View abstract ⏷
The objectives of the study were to evaluate and compare the efficacy of hexavalent chromium (Cr(VI)) removal by amino-modified (HDA-MPBC) and pristine biochar (MPBC) derived from an invasive plant Mimosa pigra. Prepared biochars were characterized and batch experiments were conducted to check the performance and the mechanisms of Cr(VI) removal. FTIR spectra revealed that the surface of HDA-MPBC is abundant with amino functional groups which was further confirmed by XPS analysis. The highest Cr(VI) removal for both HDA-MPBC (76%) and MPBC (62%) was observed at pH 3.0. The batch sorption data were well fitted to the Freundlich isotherm model and pseudo-second-order kinetic model, suggesting the involvement of both physisorption and chemisorption mechanisms for Cr(VI) removal. X-ray photoelectron spectroscopy studies showed that both Cr(VI) and Cr(III) were presented at the modified biochar surface after adsorption. These results indicated that the electrostatic attraction of Cr(VI) coupled with reduction of Cr(VI) to Cr(III) and complexation of Cr(III) ions with functional groups on HDA-MPBC as the most plausible mechanism for removal of Cr(VI) by modified biochar. Regeneration experiment concluded that adsorbed Cr(VI) onto the surface of HDA-MPBC had the least tendency of being desorbed in basic conditions. HDA-MPBC showed a high performance in adsorptive removal of Cr(VI) compared to pristine biochar signifying the amino modification to enhance adsorption performance of biochar in Cr(VI) removal from wastewater.
Strategies and options for the sustainable recovery of rare earth elements from electrical and electronic waste
Ramprasad C., Gwenzi W., Chaukura N., Izyan Wan Azelee N., Upamali Rajapaksha A., Naushad M., Rangabhashiyam S.
Review, Chemical Engineering Journal, 2022, DOI Link
View abstract ⏷
Rare earth elements (REEs) are among the important elements in various high-technological appliances globally. Recently, the recovery of REEs from the waste electrical and electronic equipment (WEEE) has gained significant interest for the sustainability of global electrical and electronic industrial markets. The fast-evolving and rapid changing of technology has made many of these hi-tech equipment become obsolete with high disposal rates. Rising concerns over the depletion of REE sources have led to the need to extract and recover the REEs from WEEE. However, many studies still need to be carried out to optimize the recovery processes of the REEs in terms of the extraction methods employed and to minimize the environmental impact and hazard towards the flora and fauna. This review outlines the various REEs available in a wide range of electrical and electronic equipment, the various types of REE recovery methods, as well as their environmental impacts. The future perspectives and research directions in terms of the circular economy, policy and regulatory framework and research roadmap for REE recovery from WEEE are also discussed.
Polypyrrole-based nanomaterials: A novel strategy for reducing toxic chemicals and others related to environmental sustainability applications
Kumar R., Raizada P., Ahamad T., Alshehri S.M., Le Q.V., Alomar T.S., Nguyen V.-H., Selvasembian R., Thakur S., Nguyen D.C., Singh P.
Article, Chemosphere, 2022, DOI Link
View abstract ⏷
Aqueous contaminants such as pharmaceuticals, dyes, personal care products, etc., are the common water contaminants that show adverse health effects. Photocatalysis is one of the well-known techniques to treat these water contaminants. Currently, most inorganic photocatalysts show a poor balance between adsorption and photocatalytic activity. In addition, heavy metal pollution and low biosafety are significant concerns in photocatalysis. Thus, environmentally friendly photocatalysts are required to avoid the secondary pollution caused by some inorganic semiconductor-photocatalysts. Organic polymer-based photocatalysts are low-cost, stable, non-toxic, and can utilize visible and NIR light for photocatalysis. In this review, we have discussed polypyrrole as a photocatalyst. Polypyrrole is a conducting organic polymer photocatalyst that is highly stable with high charge mobility and strong binding sites for photocatalytic reactions. Besides these advantages, polypyrrole has limitations, such as high charge recombination due to a small bandgap and poor dispersity. So we have explored the modifications to polypyrrole photocatalysts, such as doping and heterojunctions. Further, we have explained the applications of polypyrrole in photocatalysis as an adsorbent, sensitizer, degradation of pollutants, and energy production. Finally, the future aspects of polypyrrole photocatalysis are also explored to improve the path of future research.
Adsorption of persistent organic pollutants (POPs) from the aqueous environment by nano-adsorbents: A review
Ighalo J.O., Yap P.-S., Iwuozor K.O., Aniagor C.O., Liu T., Dulta K., Iwuchukwu F.U., Rangabhashiyam S.
Article, Environmental Research, 2022, DOI Link
View abstract ⏷
The intensification of urbanisation and industrial activities significantly exacerbates the distribution of toxic contaminations into the aqueous environment. Persistent organic pollutants (POPs) have received considerable attention in the past few decades because of their persistence, long-distance migration, potential bioaccumulation, latent toxicity for humans and wildlife. There is no doubt that POPs cause serious effects on the global ecosystem. Therefore, it is necessary to develop a simple, safe and sustainable approach to remove POPs from water bodies. Among other conventional techniques, the adsorption process has proven to be a more effective method for eliminating POPs and to a larger extent meet discharge regulations. Nanomaterials can effectively adsorb POPs from aqueous solutions. For most POPs, a >70% adsorptive removal efficiency was achieved. The major mechanisms for POPS uptake by nano-adsorbents includes electrostatic interaction, hydrophobic (van der Waals, π-π and electron donor-acceptor) interaction and hydrogen bonding. Nano-adsorbent can sustain a >90% POPs adsorptive removal for about 3 cycles and reuseable for up to 10 cycles. Challenges around adsorbent ecotoxicity and safe disposal were also discussed. The present review evaluated recent research outcomes on nanomaterials that are employed to remove POPs in water systems.
Recent progress on elemental sulfur based photocatalysts for energy and environmental applications
Kumar Y., Kumar R., Raizada P., Parwaz Khan A.A., Nguyen V.-H., Kim S.Y., Le Q.V., Selvasembian R., Singh A., Gautam S., Nguyen C.C., Singh P.
Article, Chemosphere, 2022, DOI Link
View abstract ⏷
The growing needs of the rising population and blatant misuse of resources have contributed enormously to environmental problems. Among the various methods, photocatalysis has emerged as one of the effective remediation methods. The continuous search for effective photocatalysts that can be made from abundant, cheap, non-toxic materials is going on. Although sulfur is a known insulator, recent sulfur use as a visible light photocatalyst has ushered a new era in this direction. Sulfur is a non-toxic, cheap, and abundant photocatalyst, exhibiting significant photocatalytic properties. But, hydrophobicity, poor light-harvesting and high recombination rate of charge carriers in elemental sulfur photocatalyst are some of the major drawbacks of the elemental sulfur photocatalyst. The photocatalytic activity of sulfur as a single element was low, but various methods such as nanoscaling, heterojunction formation, doping and surface modifications have been used to enhance it. The review highlights sulfur's crystal structure, electronic and optical properties, and morphological changes, making it an excellent visible light photocatalyst. The article points to the limitations of sulfur as a single photocatalyst and various strategies to improve the shortcomings. More recently, there has been an emphasis on the synthesis of metal-free photocatalysts. This review provides its readers with a comprehensive detail of sulfur being used as a dopant in improving the photocatalytic properties of metal-free photocatalysts and their environmental remediation use. Finally, the conclusion and future perspectives for sulfur-based nanostructures are presented.
Copper sulfides based photocatalysts for degradation of environmental pollution hazards: A review on the recent catalyst design concepts and future perspectives
Sudhaik A., Raizada P., Rangabhashiyam S., Singh A., Nguyen V.-H., Van Le Q., Khan A.A.P., Hu C., Huang C.-W., Ahamad T., Singh P.
Article, Surfaces and Interfaces, 2022, DOI Link
View abstract ⏷
Amongst various metal chalcogenides, CuS (copper sulfides) have been widely explored in past years due to its semiconducting behavior and non-toxic nature. CuS owns remarkable plasmonic effect and apt bandgap energy values (1.2-1.5 eV) with exceptional electronic and optical properties making it an excellent photocatalytic material. Different morphological forms of CuS have been reported with diverse bandgap energy values such as 1.88, 2.06, 2.08, and 2.16 eV for CuS nanoparticles, nanotubes, microspheres, and nanoflakes, respectively. The different forms of CuS photocatalyst mostly exhibit optical absorption in the visible near-infrared (NIR) region. The present review delivers a detailed discussion of structural, optoelectronic features of CuS nanostructures and different synthetic routes with their application in wastewater treatment. The study summarized previously reported literature by explaining innovative methodologies for developing bare CuS nanomaterials with appropriate modulations such as doped CuS photocatalysts and different CuS-based heterostructures by coupling with metal oxides, metal sulfides, and metal-free semiconductors nanomaterials (carbonaceous materials) to enhance the photocatalytic activity of CuS. The heterojunctions of CuS with other photocatalysts have been extensively studied to validate the enhancement in photocatalytic activity of bare CuS photocatalysts towards different pollutants. Concluding perspectives on the challenges and opportunities for CuS-based photocatalysts to degrade environmental pollution hazards are also highlighted.
A Review on Carbon Quantum Dots Modified g-C3N4-Based Photocatalysts and Potential Application in Wastewater Treatment
Patial S., Sonu, Sudhaik A., Chandel N., Ahamad T., Raizada P., Singh P., Chaukura N., Selvasembian R.
Review, Applied Sciences (Switzerland), 2022, DOI Link
View abstract ⏷
Carbon quantum dots (CDs) are a fascinating class of carbon nanomaterials (less than 10 nm in size) with unique optical, electrical, and physicochemical properties. In addition to these properties, CQDs exhibit the desired advantages of aqueous stability, low toxicity, high surface area, economic feasibility, chemical inertness, and highly tunable photoluminescence behaviour. Recently, graphitic carbon nitride (g-C3N4) has appeared as one of the required stable carbon-based polymers due to its varied applications in several fields. In this regard, modification strategies have been made in the g-C3N4 semiconductor using CQDs to enhance the adsorptive and photocatalytic activity. In comparison to other semiconductor quantum dots, g-C3N4 shows strong fluorescent properties, such as wide excitation spectra, photostability, and tunable photo-luminescent emission spectra. The interaction inside this multicomponent photocatalyst further promotes the photocatalytic activity by improving charge transference, which plays a vital role in electrochemistry. Therefore, CQDs are auspicious nanomaterials in the field of photocatalysis, wastewater treatment and water adsorption treatment. This particular article featured the recent progression in the field of CDs/g-C3N4-based photocatalysts focusing on their luminescent mechanism and potential applications in wastewater treatment.
Bioremediation of metal(loid) cocktail, struvite biosynthesis and plant growth promotion by a versatile bacterial strain Serratia sp. KUJM3: Exploiting environmental co-benefits
Mondal M., Kumar V., Bhatnagar A., Vithanage M., Selvasembian R., Ambade B., Meers E., Chaudhuri P., Biswas J.K.
Article, Environmental Research, 2022, DOI Link
View abstract ⏷
In this study the multiple metal(loid) (As, Cd, Cu and Ni) resistant bacterium Serratia sp. KUJM3 was able to grow in both single and multiple metal(loid) contaminated wastewater and removed them by 34.93–48.80% and 22.93–32%, respectively. It reduced As(v) to As(III) by 68.44–85.06% in a concentration dependent manner. The strain's IAA production potential increased significantly under both metal(loid)s regime. The lentil (Lens culinaris) seed germination and seed production were enhanced with the exogenous bacterial inoculation by 20.39 and 16.43%, respectively. Under both multi-metal(loid) regimes the bacterial inoculation promoted shoot length (22.65–51.34%), shoot dry weight (33.89–66.11%) and seed production (13.46–35%). Under bacterial manipulation the metal(loid)s immobilization increased with concomitant curtailment of translocation in lentil plant by 61.89–75.14% and 59.19–71.14% in shoot and seed, respectively. The strain biomineralized struvite (MgNH4 PO4 ·6H2O) from human urine @ 403 ± 6.24 mg L−1. The fertilizer potential of struvite was confirmed with the promotion of cowpea (Vigna unguiculata) growth traits e.g. leaf number (37.04%), pod number (234%), plant wet weight (65.47%) and seed number (134.52%). Thus Serratia sp. KUJM3 offers multiple benefits of metal(loid)s bioremediation, As(V) reduction, plant growth promotion, and struvite biomineralization garnering a suite of appealing environmental applications.
Omics reflection on thebacterial escape from the toxic trap of metal(loid)s: Cracking the code of contaminants stress, resistance repertoire, and remediation
Biswas J.K., Mondal M., Kumar V., Vithanage M., Selvasembian R., Ambade B., Kumar M.
Book chapter, Omics for Environmental Engineering and Microbiology Systems, 2022, DOI Link
Global Climate Change
Singh S., Singh P., Rangabhashiyam S., Srivastava K.K.
Book, Global Climate Change, 2021, DOI Link
View abstract ⏷
Global Climate Change presents both practical and theoretical aspects of global climate change from across geological periods. It addresses holistic issues related to climate change and its contribution in triggering the temperature increase with a multitude of impacts on natural processes. As a result, it helps to identify the gaps between policies that have been put in place and the continuously increasing emissions. The challenges presented include habitability, biodiversity, natural resources, and human health. It is organized into information on the past, present, and future of climate change to lead to a more complete understanding and therefore effective solutions. Placing an emphasis on recent climate change research, Global Climate Change helps to bring researchers and graduate students in climate science, environmental science, and sustainability up to date on the science of climate change so far and presents a baseline for how to move into the future effectively.
Preface
Selvasembian R., Singh P.
Editorial, Biosorption for Wastewater Contaminants, 2021,
Recent advances on water disinfection using bismuth based modified photocatalysts: Strategies and challenges
Kumar R., Raizada P., Verma N., Hosseini-Bandegharaei A., Thakur V.K., Le Q.V., Nguyen V.-H., Selvasembian R., Singh P.
Review, Journal of Cleaner Production, 2021, DOI Link
View abstract ⏷
Among the various problems associated with environment, water pollution is a critical concern. Harmful microorganisms present in polluted water cause various dangerous diseases and ultimately lead to millions of deaths, worldwide. Various techniques like chlorination, ozonation, UV radiations etc. are used for water disinfection but most of them are either less efficient or give rise to secondary toxic products. Nowadays, photocatalysis is considered as one of the most efficient cleaner production technique for water disinfection. In the present review, we have discussed water disinfection via bismuth based photocatalysts. Most of bismuth based photocatalysts are stable, visible light active, reusable, cost-effective and non-toxic. By reviewing the current literature, we have explored the basic mechanism of bacterial inactivation via photocatalysis. Further, various bismuth based photocatalysts (bismuth oxides, bismuth sulfides, Bi2MoO6, Bi2WO6, BiVO4 and bismuth oxyhalides) for bacterial inactivation are discussed. Furthermore, due to some drawbacks of pristine photocatalysts such as charge carrier recombination, slow migration of charge carriers, low visible light absorption, etc., we have discussed the modified bismuth based photocatalysts for water disinfection. Modifications viz. heterojunction, Z-scheme, doping etc. are investigated for some important bismuth based photocatalysts. Finally, challenges against bismuth based photocatalysts and future aspects for further research are also explored.
Biosorption for Wastewater Contaminants
Selvasembian R., Singh P.
Book, Biosorption for Wastewater Contaminants, 2021, DOI Link
View abstract ⏷
Pollution due to various anthropogenic activities continues to increase. In terms of water pollutants, organic and inorganic pollutants are the most problematic. Although several measures have been proposed and implemented to prevent or reduce contamination, their increased concentration in water bodies has created serious concerns. Over the years, the problem has been aggravated by industrialization, urbanization and the exploitation of natural resources. The direct discharge of wastewater contaminants and their geographical mobilization have caused an increase in concentration in ground, surface, fluvial and residual waters. Extensive information about detection and disposal methods is needed in order to develop technological solutions for a variety of environments, both urban and rural. This book provides up-to-date information on wastewater contaminants, aimed at researchers, engineers and technologists working in this field. Conventional physicochemical techniques used to remove contaminants from wastewater include ion exchange, precipitation, degradation, coagulation, coating, membrane processes and adsorption. However, these applications have technological and economic limitations, and involve the release of large amounts of chemical reagents and by-products that are themselves difficult to remove. Biosorption - the use of organically generated material as an adsorbent – is attracting new research and scholarship. Thermally-treated calcined biomaterials may be treated to remove heavy metals from wastewater. To ensure the elimination of these contaminants, existing solutions must be integrated with intelligent biosorption functions. Biosorption for Wastewater Contaminants will find an appreciative audience among academics and postgraduates working in the fields of environmental biotechnology, environmental engineering, wastewater treatment technology and environmental chemistry.
Environmental and health impacts of contaminants of emerging concerns: Recent treatment challenges and approaches
Yadav D., Rangabhashiyam S., Verma P., Singh P., Devi P., Kumar P., Hussain C.M., Gaurav G.K., Kumar K.S.
Article, Chemosphere, 2021, DOI Link
View abstract ⏷
In the past few decades, new contaminants of emerging concern (CECs) in the air, water, and soil have gained significant attention due to their adverse impact on human health and the environment. The sources of CECs have been identified in different forms from domestic and industrial activities such as personal care products and pharmaceuticals. It has been established that aqueous medium plays a major role in the dissemination of various contaminants, like drinking water, reservoirs, lakes, rivers and waste with water medium. There remains inadequate technology for the treatment of CECs in the wastewater systems. Though different techniques have advanced for the treatment of CECs, they still pose a severe threat to human health and disturb the ecological balance. In this review, the characteristics, recent technologies, risk assessment and management of CECs have been discussed. The primary aim is to highlight the new innovative and cost-effective technologies for the remediations of CECs in all forms. Biochar is readily and economically available in abundance and an economical adsorbent with 100% adsorptive removal for H2PO4−. The bibliometric analysis also performed to understand the emerging research trends on the treatment techniques, which can help in developing a guiding pathway to modern research in academia and industry.
Progress on the photocatalytic reduction of hexavalent Cr (VI) using engineered graphitic carbon nitride
Hasija V., Raizada P., Singh P., Verma N., Khan A.A.P., Singh A., Selvasembian R., Kim S.Y., Hussain C.M., Nguyen V.-H., Le Q.V.
Review, Process Safety and Environmental Protection, 2021, DOI Link
View abstract ⏷
The existence of chromium in hexavalent oxidation state is highly toxic to aquatic environment. Photocatalytic reduction of hexavalent Cr (VI) into Cr (III) has emerged as a desirable technology due to their prospect in solar energy utilization, high efficiency and low cost. Graphitic carbon nitride (g-C3N4)-based photocatalysts are ideal for Cr (VI) reduction due to their inherent features including; visible-light responsive narrow bandgap, suitable conduction band potential, high physicochemical stability, unique optical and electronic properties. Herein, various surface-interface strategies to modify g-C3N4 including heterojunction formation, doping, structural regulation, co-catalyst loading and construction of nitrogen vacancies are elaborated for improving the Cr(VI) photoreduction efficiency. The review also highlights the effect of operational reaction conditions such solution pH, g-C3N4 dosage, Cr (VI) concentration, temperature, light source, organic acid additives and co-existing ions influencing Cr (VI) reduction efficiency. Finally, we attempt to propose the existing issues based on the current research and future aspects of engineered g-C3N4 for Cr (VI) photoreduction.
An environmental approach for the photodegradation of toxic pollutants from wastewater using silver nanoparticles decorated titania-reduced graphene oxide
Ojha A., Singh P., Oraon R., Tiwary D., Mishra A.K., Ghfar A.A., Naushad M., Ahamad T., Thokchom B., Vijayaraghavan K., Rangabhashiyam S.
Article, Journal of Environmental Chemical Engineering, 2021, DOI Link
View abstract ⏷
Light-induced demineralization of organic pollutants is a recent development in the field of waste treatment. The present study focuses on TiO2-rGO-Ag hybrid nanocomposite through a two-step simultaneous synthesis pathway. The methods primarily involving facile solvothermal treatment (TiO2-rGO nanocomposite) in a water-ethanol mixture, followed by microwave irradiation method for deposition of silver (Ag) nanoparticles over the Binary nanocomposite synthesized. The resulting hybrid photocatalyst was well, and in-detail characterized using analytical techniques such as High-Resolution X-ray Diffractometer (HR-XRD), Transmission Electron Microscopy and High-Resolution Transmission Electron Microscopy (TEM/HR-TEM), High-Resolution Scanning Electron Microscopy (HR-SEM), Fourier-Transform Infra-Red Spectroscopy (FT-IR), Energy Dispersive X-Ray Spectroscopy (EDX), Raman Spectroscopy, Solid-State UV–Vis Spectroscopy and X-Ray Photoelectron spectroscopy (XPS). The nanomaterial was examined to determine photocatalytic property by conducting a photodegradation experiment of an aqueous solution of Methylene Blue (MB) dye and monitoring the changes. The photocatalytic efficiency of the nano-hybrid synthesized was also analyzed in detail for the degradation of compounds that active components of petrochemical pollutants such as Benzene, Toluene, and Phenol the Visible region of radiation in a photochemical reactor under ambient reaction conditions. The set of experiments suggested that the photocatalytic efficiency of ternary nanocomposite synthesized was quite noticeable. The variation in the catalyst's photoactivity with the change in the functional group was monitored, and the rate of reaction has been correlated with attached substituents.
An overview on cellulose-supported semiconductor photocatalysts for water purification
Rana A., Sudhaik A., Raizada P., Khan A.A.P., Van Le Q., Singh A., Selvasembian R., Nadda A., Singh P.
Review, Nanotechnology for Environmental Engineering, 2021, DOI Link
View abstract ⏷
Metal oxides have been widely used in wastewater treatment, but due to their limitations there is a need of some modifications to make them an efficient photocatalyst. Many support materials are used to enhance the photocatalytic efficacy of many photocatalysts. Recently, cellulose nanomaterials have been utilized as green prototype for the preparation of metal or metal oxide nanomaterials and to improve their photocatalytic efficacy as it acts as a good adsorbent and support material. Cellulose fibers (macro and nano) have gathered the interest of scientific community due to its easy fabrication and some unique possessions. Through immobilization, photocatalysts can be used for the removal of pollutants by fixing the raw catalyst powder onto a support material. Physical adsorption and covalent binding on carrier substance are various strategies for immobilization. In composites, cellulose fibers (macro and nano) have been utilized as a driving force owing to its structural properties (presence of functional groups, i.e., carboxylic, hydroxyl, methoxy and phenolic groups) and hydrophilic nature which helps in increasing surface roughness in composites. The present review offers an outlook on metal oxides, their limitations, immobilization and support materials where cellulose performed as support (to enhance surface area), adsorbent, immobilized and functionalized material to minimize the limitation of metal oxides. The main focus of this review is on different role of cellulose materials which describes the fundamental properties of cellulose and its amendments by coupling with other metal oxides such as TiO2, ZnO, Ag and phosphates.
Statistical modeling and mechanistic pathway for methylene blue dye removal by high surface area and mesoporous grass-based activated carbon using K2CO3activator
Abdulhameed A.S., Firdaus Hum N.N.M., Rangabhashiyam S., Jawad A.H., Wilson L.D., Yaseen Z.M., Al-Kahtani A.A., Alothman Z.A.
Article, Journal of Environmental Chemical Engineering, 2021, DOI Link
View abstract ⏷
In this study, biomass of grass waste (GW) was utilized as sustainable precursor to produce highly porous activated carbon (GWAC) with mesoporosity using a K2CO3-assisted pyrolysis approach and tested for its methylene blue (MB) dye adsorption properties. The prepared GWAC was characterized using the various techniques of specific surface area (SSA), Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX), X-ray diffractometer (XRD), thermogravimetric analysis (TGA), and Fourier Transform Infrared (FT-IR) spectrophotometer. The characterization results indicate the successful conversion of GW into mesoporous GWAC with high and desirable surface area of 1245.6 m2/g. The adsorptive performance of GWAC towards MB uptake was evaluated. To attain higher performance of the activated carbon for MB adsorption, the adsorption key parameters such as GWAC dosage (A: 0.04-0.06 g/L), pH (B: 4-10), temperature (C: 30-60 °C), and time (D: 5-15 min) were optimized using the Box-Behnken design (BBD) method. The adsorption equilibrium data were accurately described by the Langmuir model, where the adsorption capacity (qm; 364.2 mg/g) was recorded at the optimized process temperature of 45 °C. The present research also examined the mechanisms associated with the removal of MB using GWAC and observed the contribution of various MB-GWAC surface interactions (e.g., electrostatic, π-π, and H-bonding interactions). The present investigation shows the utility and effectiveness of GW biomass based activated carbon due to its favorable mesoporosity and cationic dye uptake in aqueous media.
Sustainable approach of batch and continuous biosorptive systems for praseodymium and thulium ions removal in mono and binary aqueous solutions
Rangabhashiyam S., Vijayaraghavan K., Jawad A.H., Singh P.
Article, Environmental Technology and Innovation, 2021, DOI Link
View abstract ⏷
With advancement of technologies in most of the sectors, the market requirement for the rare earth elements (REEs) increasing at a rapid rate. Hence, it is vital to recover REEs from wastewater. Thus, in the present study, biosorptive uptake of praseodymium (Pr(III)) and thulium (Tm(III)) ions from mono and binary solutions using polysulfone-immobilized Turbinaria conoides (PITC) were examined for the first time The sorption of Pr(III) and Tm(III) ions were performed in batch and column biosorption systems. The biosorptional uptakes of PITC for Pr(III) and Tm(III) in mono solution were found as 1.14 and 1.23 mmol/g, respectively. The equilibrium biosorption data of the mono system were examined through the Langmuir and Freundlich isotherms, whereas data of binary biosorption experiments were checked with Sheindorf–Rebhun–Sheintuch and extended Langmuir isotherm model. The desorption efficiency of PITC in batch system showed recovery of Pr(III) and Tm(III) more than 95.5% up to 5 cycles. Continuous biosorption models like the Thomas, Yoon–Nelson and modified dose–response were employed to understand continuous biosorption behavior, and model constants were determined. The column desorption efficiency were observed as 98.9% (Pm(III)) and 99.5% (Tm(III)). Good biosorption capacity, desorption and reuse potential of PITC illustrated the environmental friendliness and scalable features.
Sustainable and Green Engineering Insights on Deep Eutectic Solvents toward the Extraction of Nutraceuticals
Balaraman H., Selvasembian R., Rangarajan V., Rathnasamy S.
Review, ACS Sustainable Chemistry and Engineering, 2021, DOI Link
View abstract ⏷
Deep eutectic solvents (DES) hold promising potential in the selective purification of bioactive molecules from various complex sources. Although they are increasingly considered as a biocompatible extraction medium, adding the task-specific functionality, which makes DES distinctive for the selective extraction of compounds, requires appropriate tailoring of their physical properties. This critical review investigates the influential physical properties of deep eutectic solvents and their effect on various sustainable extraction methods - including both solid-liquid and liquid-liquid - for the separation of nutraceuticals. Various methods by which DES are employed as solvents, cosolvents, or as adjuvants in different extraction systems are compared in terms of their efficiency and selectivity. Furthermore, the correspondence between the type of DES and the nature of target nutraceuticals to be extracted is also discussed. The Review highlights the key achievements and future prospects of employing DES along with the lacunae in the current investigations and proposed various approaches for sustainable applications.
Recent advances in the polyurethane-based adsorbents for the decontamination of hazardous wastewater pollutants
Selvasembian R., Gwenzi W., Chaukura N., Mthembu S.
Review, Journal of Hazardous Materials, 2021, DOI Link
View abstract ⏷
The pollution of aquatic systems with noxious organic and inorganic contaminants is a challenging problem faced by most countries. Water bodies are contaminated with diverse inorganic and organic pollutants originating from various diffuse and point sources, including industrial sectors, agricultural practices, and domestic wastes. Such hazardous water pollutants tend to accumulate in the environmental media including living organisms, thereby posing significant environmental health risks. Therefore, the remediation of wastewater pollutants is a priority. Adsorption is considered as the most efficient technique for the removal of pollutants in aqueous systems, and the deployment of suitable adsorbents plays a vital role for the sustainable application of the technique. The present review gives an overview of polyurethane foam (PUF) as an adsorbent, the synthesis approaches of polyurethane, and characterization aspects. Further emphasis is on the preparation of the various forms of polyurethane adsorbents, and their potential application in the removal of various challenging water pollutants. The removal mechanisms, including adsorption kinetics, isotherms, thermodynamics, and electrostatic and hydrophobic interactions between polyurethane adsorbents and pollutants are discussed. In addition, regeneration, recycling and disposal of spent polyurethane adsorbents are reported. Finally, key knowledge gaps on synthesis, characterization, industrial applications, life cycle analysis, and potential health risks of polyurethane adsorbents are discussed.
ZnS-based quantum dots as photocatalysts for water purification
Sharma K., Raizada P., Hasija V., Singh P., Bajpai A., Nguyen V.-H., Rangabhashiyam S., Kumar P., Nadda A.K., Kim S.Y., Varma R.S., Le T.T.N., Le Q.V.
Review, Journal of Water Process Engineering, 2021, DOI Link
View abstract ⏷
Solar-light-driven photocatalysis is an emerging, renewable and sustainable approach in environmental remediation to mitigate organic pollutants from waste water. Zinc sulfide quantum dots (ZnS QDs) have been utilized because of their larger surface area, low cost, abundant active sites, non-toxic nature, aqueous insolubility, and good thermal stability. Ascribing to the quantum confinement effect, the accumulation of the electrons inside the QDs leads to an increase in the light absorption range. Herein, the effect of various parameters, like pH and temperature variation are summarized that determines the size and varied morphologies of ZnS QDs including their synthesis via solvothermal, hydrothermal, coprecipitation, microwave-assisted method, and other emerging greener approaches. In view of inherent deficiencies in ZnS QDs namely bandgap alignment and high recombination rate, some modification strategies like doping and heterojunction formation have been explored. Doping is preferred for tuning the band gaps for light absorption upto near-infrared region (NIR) that results in enhanced photocatalytic proficiency. The formation of heterojunction strategies has been put forth owing to the effective charge separation and migration ability. Finally, an outlook regarding unresolved challenges about ZnS QDs photocatalyst is projected for future perspectives in this arena.
RSM-CCD optimization approach for the adsorptive removal of Eriochrome Black T from aqueous system using steel slag-based adsorbent: Characterization, Isotherm, Kinetic modeling and thermodynamic analysis
Manzar M.S., Khan G., dos Santos Lins P.V., Zubair M., Khan S.U., Selvasembian R., Meili L., Blaisi N.I., Nawaz M., Abdul Aziz H., Kayed T.S.
Article, Journal of Molecular Liquids, 2021, DOI Link
View abstract ⏷
The waste from the steel industries is disposed of in landfills or used in construction and improvement of the soil. Since these wastes are reported as adsorbents for water pollutants, two steel dust/slag wastes, Alrhaji (AL) and Arab (AR) materials, were applied for Eriochrome Black T dye (EBT) removal from the aqueous system. The materials were characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), N2 adsorption/desorption analysis, transmission electron microscopy (TEM), Fourier transform-IR (FTIR), and X-ray diffraction (XRD). The performances of adsorbents (i.e., q = 34.82 mg/g for AL and q = 38.88 mg/g for AR at 45 °C) result in promising values compared to other adsorbents reported for EBT removal. The equilibrium data provided good fit for Sips model (AL) and Langmuir model (AR) showed the highest values of R2 and lower values of average relative error (ARE). The kinetic data was best represented by the pseudo-second order model for both adsorbents. The thermodynamic studies indicate a physisorption adsorbent/adsorbate interaction with slight structural modifications in AR surface and the randomness reductions at the adsorption surfaces for AL adsorbent. Considering the results of the present investigations, the Alrhaji and Arab steel slags are promising adsorbents for EBT removal from the aqueous system.
Efficient adsorption of dyes by γ-alumina synthesized from aluminum wastes: Kinetics, isotherms, thermodynamics and toxicity assessment
Fernandes E.P., Silva T.S., Carvalho C.M., Selvasembian R., Chaukura N., Oliveira L.M.T.M., Meneghetti S.M.P., Meili L.
Article, Journal of Environmental Chemical Engineering, 2021, DOI Link
View abstract ⏷
This study aimed at synthesizing γ-alumina from aluminum residue obtained from a frame fabrication factory, through precipitation followed by calcination, and apply it as an adsorbent to remove dyes from aqueous solution. The produced adsorbent was designated as non-rigid of aggregates of irregularly shaped particles, with a plate format, a mesoporous structure and with high surface area (304.31 m2·g−1). The kinetic studies indicated the adsorption of methylene blue (MB) follows the pseudo-first order model, while the pseudo-second order best fitted in case of the adsorption of crystal violet (CV) and basic fuchsin (BF). The equilibrium studies indicated the adsorption process is exothermic and the Langmuir model best fitted the equilibrium data with qmax equal to 57.81, 32.92 and 31.92 mg·g−1 for MB, BF and CV, respectively. The adsorption capacity of synthesized alumina from waste was compared with commercial ones and proved to be superior in surface area and adsorption capacity, where this was 40–60% higher for the analyzed dyes. The thermal regeneration was effectively reported towards the attainment of 3 complete cycles of dyes adsorption/desorption. The toxicity assays using Artemia salina and Lactuca sativa as biomarkers reinforce adsorption results demonstrating the treatment of dye solutions by γ-alumina can decrease the mortality of the microcrustaces and the phytotoxicity of solutions. The obtained results indicated some minimum feasibility of the proposed material to be applied in real contamination scenarios.
Sustainable and green trends in using plant extracts for the synthesis of biogenic metal nanoparticles toward environmental and pharmaceutical advances: A review
Soni V., Raizada P., Singh P., Cuong H.N., S R., Saini A., Saini R.V., Le Q.V., Nadda A.K., Le T.-T., Nguyen V.-H.
Article, Environmental Research, 2021, DOI Link
View abstract ⏷
Conventionally utilized physical and chemical routes for constructing nanoparticles are not eco-friendly. They are associated with many shortcomings like the requirement of specially designed equipment, templates, extremely high temperature, and pressure. Biosynthesis seems to be drawn unequivocal attention owing to its upsurge of applications in different fields like; energy, nutrition, pharmaceutical, and medicinal sciences. To harness the biological sources, the present review describes an environment-friendly route to generate biogenic nanoparticles from the natural plant extracts and the followed mechanisms for their synthesis, growth, and stabilization. The present review summarizes the recent trends involved in the photosynthesis of metallic nanoparticles and their effective use in controlling malaria, hepatitis, cancer, like various endemic diseases. Also, various characterization approaches, such as UV–visible spectrophotometry, Fourier transform infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy, are discussed here examine the properties of as-fabricated nanoparticles. Various plant parts like leaves, stems, barks, fruit, and flowers are rich in flavonoids, phenols, steroids, terpenoids, enzymes, and alkaloids, thereby playing an essential role in reducing metal ions that generate metallic nanoparticles. Herein, the uniqueness of phytofabricated nanoparticles along with their distinctive antibacterial, antioxidant, cytotoxic, and drug delivery properties are featured. Lastly, this work highlights the various challenges and future perspectives to further synthesize biogenic metal nanoparticles toward environmental and pharmaceutical advances in the coming years.
Toward practical solar-driven photocatalytic water splitting on two-dimensional MoS2 based solid-state Z-scheme and S-scheme heterostructure
Raizada P., Nguyen T.H.C., Patial S., Singh P., Bajpai A., Nguyen V.-H., Nguyen D.L.T., Cuong Nguyen X., Aslam Parwaz Khan A., Rangabhashiyam S., Young Kim S., Le Q.V.
Article, Fuel, 2021, DOI Link
View abstract ⏷
Solar-driven splitting of water to hydrogen production is one of the utmost auspicious and cost-effective technologies providing sustainable fuel as it necessitates only sunlight and water. This substantial technology can be achieved in a two step-photoexcitation system using an artificial Z-scheme process. The key to comprehend this reaction is to discover an effective and robust photocatalyst which preferably makes sufficient use of solar energy. Benefiting from the ultrahigh surface area, appropriate band potentials and unique physiochemical properties of 2D layered structure, MoS2 has attained intensive research attention for hydrogen evolution reaction. The comprehensive review summarizes the recent progression in solid mediator Z-scheme based MoS2 particularly in the field of water splitting. The review initiates with the important bases of Z-scheme water splitting mechanism in addition to structural and optoelectronic properties of MoS2. In addition, detailed discussion on the solid-mediator Z-schemes to further improve the photocatalytic efficacy and limit the back (water-forming) reactions. The review mainly focuses on the solid-mediator based Z-schematic systems involving new tandem structures with an efficient synergistic effect to achieve both wide-range light absorptivity and charge pairs transference. In addition, a new S-scheme heterostructing is briefly introduced to understand the charge-transport route clearly and vividly. The aim of wide-spreading water splitting devices from lab-scale to wide-range potential applications has been considered as ‘artificial photosynthetic leaf-to-tree challenge’. Finally, a summary and outlook on the challenges and future research topics on MoS2 based Z-scheme heterostructure photocatalysts are presented.
Controllable functionalization of g-C3N4 mediated all-solid-state (ASS) Z-scheme photocatalysts towards sustainable energy and environmental applications
Sharma S., Dutta V., Raizada P., Khan A.A.P., Le Q.V., Thakur V.K., Biswas J.K., Selvasembian R., Singh P.
Article, Environmental Technology and Innovation, 2021, DOI Link
View abstract ⏷
As an interesting conjugated polymer, g-C3N4 has drawn huge interdisciplinary consideration as the latest research “hotspot” in energy conversion and wastewater mitigation. Nonetheless, due to less surface area and charge carrier transfer photocatalytic efficacy of g-C3N4 is restricted. Lately, new advancements has been attained concerning avant-garde all-solid-state (ASS) Z-scheme systems to boost photocatalytic efficiency. Therefore, coupling g-C3N4 photocatalyst with appropriate photocatalyst to construct ASS Z-scheme structure proposes a significant way to enhance charge separation, expand the specific surface area and boost catalytic performance. This review extensively aims at g-C3N4 based ASS Z-scheme photocatalysts grounded on their structure, DFT calculations, photocatalytic properties, interface charge transfer, and drawbacks. We have predominantly introduced various techniques to enhance catalytic performances of g-C3N4 grounded ASS Z-scheme semiconductor photocatalysts. Apart from this, photocatalytic applications towards CO2 reduction, water splitting, bacterial disinfection, pollutant degradation are systematically discussed. Lastly, challenges and invigorating perspectives that g-C3N4 grounded ASS Z-scheme semiconductor photocatalysts face are recapitulated and explored. In current paper, we have extensively focused on g-C3N4 based ASS Z-scheme systems and expect that the present review on rapid-improving pace of research field is apt for engineering g-C3N4 grounded ASS Z-scheme photocatalysts for sustainable advanced applications.
Photocatalytic inactivation of viruses using graphitic carbon nitride-based photocatalysts: Virucidal performance and mechanism
Hasija V., Patial S., Singh P., Nguyen V.-H., Van Le Q., Thakur V.K., Hussain C.M., Selvasembian R., Huang C.-W., Thakur S., Raizada P.
Review, Catalysts, 2021, DOI Link
View abstract ⏷
The prevalence of lethal viral infections necessitates the innovation of novel disinfection techniques for contaminated surfaces, air, and wastewater as significant transmission media of disease. The instigated research has led to the development of photocatalysis as an effective renewable solar-driven technology relying on the reactive oxidative species, mainly hydroxyl (OH●) and superoxide (O2●−) radicals, for rupturing the capsid shell of the virus and loss of pathogenicity. Metal-free graphitic carbon nitride (g-C3N4), which possesses a visible light active bandgap structure, low toxicity, and high thermal stability, has recently attracted attention for viral inactivation. In addition, g-C3N4-based photocatalysts have also experienced a renaissance in many domains, including environment, energy conversion, and biomedical applications. Herein, we discuss the three aspects of the antiviral mechanism, intending to highlight the advantages of photocatalysis over traditional viral disinfection techniques. The sole agenda of the review is to summarize the significant research on g-C3N4-based photocatalysts for viral inactivation by reactive oxidative species generation. An evaluation of the photocatalysis operational parameters affecting viral inactivation kinetics is presented. An overview of the prevailing challenges and sustainable solutions is presented to fill in the existing knowledge gaps. Given the merits of graphitic carbon nitride and the heterogeneous photocatalytic viral inactivation mechanism, we hope that further research will contribute to preventing the ongoing Coronavirus pandemic and future calamities.
COVID-19 pandemic in Uttarakhand, India: Environmental recovery or degradation?
Nandan A., Siddiqui N.A., Singh C., Aeri A., Gwenzi W., Ighalo J.O., de Carvalho Nagliate P., Meili L., Singh P., Chaukura N., Rangabhashiyam S.
Article, Journal of Environmental Chemical Engineering, 2021, DOI Link
View abstract ⏷
The human coronavirus disease-2019 (COVID-19) caused by SARS-CoV-2 is now a global pandemic. Personal hygiene such as hand-washing, the use of personal protective equipment, and social distancing via local and national lockdowns are used to reduce the risk of transmission of SARS-CoV-2. COVID-19 and the associated lockdowns may have significant impacts on environmental quality and ergonomics. However, limited studies exists on the impacts of COVID-19 and the associated lockdowns on environmental quality and ergonomics in low-income settings. Therefore, the present study investigated the impacts of the COVID-19 outbreak on socioeconomics, ergonomics and environment (water quality, air quality and noise) in Uttarakhand, India. Approximately 55% of respondents experienced headaches, and the other common health-related issue was back pain, with 45% of respondents having problems with their backs. Water and air quality significantly improved during the lockdown relative to the pre-lockdown period, but was observed to return to their previous characteristics afterwards. Lockdowns significant increased the concentration of indoor air pollutants while noise pollution levels significantly declined. In summary, lockdowns have adverse impacts on ergonomics, resulting in work-related human health risks. The impacts of lockdowns on environmental quality are mixed: temporary improvements on water and air quality, and noise reduction were observed, but indoor air quality deteriorated. Therefore, during lockdowns there is a need to minimize the adverse environmental and ergonomic impacts of lockdowns while simultaneously enhancing the beneficial impacts.
Magnetic Chitosan-Glutaraldehyde/Zinc Oxide/Fe3O4 Nanocomposite: Optimization and Adsorptive Mechanism of Remazol Brilliant Blue R Dye Removal
Reghioua A., Barkat D., Jawad A.H., Abdulhameed A.S., Rangabhashiyam S., Khan M.R., ALOthman Z.A.
Article, Journal of Polymers and the Environment, 2021, DOI Link
View abstract ⏷
A magnetic Schiff’s base chitosan-glutaraldehyde/Fe3O4 composite (CHT-GLA/ZnO/Fe3O4) was developed by incorporating zinc oxide (ZnO) nanoparticles into its structure to prepare an efficient adsorbent for the removal of remazol brilliant blue R (RBBR) dye. The CHT-GLA/ZnO/Fe3O4 was characterized by the following methods: CHN, BET, FTIR, XRD, SEM–EDX, pHpzc, and potentiometric titrations. Box-Behnken design based on response surface methodology was used to optimize the effects of the A: ZnO nanoparticles loading (0–50%), B: dose (0.02–0.1 g), C: pH (4–10), D: temperature (30–60 °C), and time E: (10–60 min) on the synthesis of the magnetic adsorbent and the RBBR dye adsorption. The experimental data of kinetics followed the pseudo-second order model, while isotherms showed better fit to Freundlich and Temkin models. The maximum adsorption capacity of the target nanocomposite (CHT-GLA/Fe3O4 containing 25% ZnO or CHT-GLA/ZnO/Fe3O4-25) was reached of 176.6 mg/g at 60 °C. The adsorption mechanism of RBBR onto CHT-GLA/ZnO/Fe3O4 nanocomposite can be attributed to multi-interactions including electrostatic attractions, hydrogen bonding, Yoshida H-bonding, and n-π interactions. This study offers a promising hybrid nanobiomaterial adsorbent in environmental nanotechnology to separate and remove the contaminants such as organic dyes from wastewater.
Understanding the microstructure, mineralogical and adsorption characteristics of guar gum blended soil as a liner material
Subramani A.K., Ramani S.E., Selvasembian R.
Article, Environmental Monitoring and Assessment, 2021, DOI Link
View abstract ⏷
Guar gum blended soil (GGBS) offers potentially advantageous engineering characteristics of hydraulic conductivity and strength for a soil to be used as a liner material. Characterization techniques such as X-ray diffraction, X-ray fluorescence, Fourier transform infrared spectroscopy and scanning electron microscope were used to examine the mineral composition, functional groups and morphological changes in the unblended soil (UBS) and GGBS. These characterization approaches are used to understand adsorption-associated mechanisms of Pb(II) removal. Batch adsorption tests were performed to evaluate the adsorption capacity of UBS and the GGBS with various proportions (0.5%, 1.0%, 1.5% and 2.0%) of guar gum (GG) towards the removal of Pb(II) ions. Batch adsorption experiments were conducted by varying the pH, dosage of adsorbent, concentration of metal ions and contact time. The experimental results showed that the optimum removal of Pb(II) ions was high at a pH of 3.0 for all blends, and adsorption tests beyond 3.0 pH demonstrated a decline in adsorption performance. The maximum Pb(II) removal efficiency of 95% was obtained using the 2.0% GGBS. The isotherm model assessment for adsorption experimental data of Pb(II) showed the best fit for the Langmuir model on using GG. The present research demonstrated that the guar gum–treated blends exhibited potential Pb(II) ion adsorption properties and therefore can be used as sustainable liner material in sanitary landfills.
Phenolic compounds degradation: Insight into the role and evidence of oxygen vacancy defects engineering on nanomaterials
Kumar A., Raizada P., Khan A.A.P., Nguyen V.-H., Van Le Q., Singh A., Saini V., Selvasembian R., Huynh T.-T., Singh P.
Review, Science of the Total Environment, 2021, DOI Link
View abstract ⏷
Oxygen vacancy as a typical point defect has incited substantial interest in photocatalysis due to its profound impact on optical absorption response and facile isolation of photocarriers. The presence of oxygen vacancy can introduce the midgap defect states, which promote extended absorption in the visible region. The redistribution of electron density at the surface can stimulate the adsorption and activation kinetics of adsorbates, manifesting optimal photocatalytic performance. Despite such alluring outcomes, the ambiguity in understanding the precise location, appropriate concentration, and oxygen vacancy role is still a long-standing task. The present review article comprehensively outlines the identification of oxygen vacancy defects at bulk or on the surface and its ultimate effect on the photocatalytic degradation of phenolic compounds. Particular emphasis has been drawn to summarize the critical influence of oxygen vacancy on different factors such as crystal structure, bandgap energy, electronic structure, and charge carrier mobility by integrating experimental results and theoretical calculations. We have also explored the reaction pathways and the intermediate chemistry of phenol photodegradation by analyzing the molecular activation (O2, H2O, and sulphate activation) through oxygen vacancy defects. Finally, the review concludes with the various challenges and future perspectives, aiming to provide a firm base for further progressions towards photocatalysis.
Disinfection by-products in drinking water: detection and treatment methods
Hariganesh S., Vadivel S., Maruthamani D., Rangabhashiyam S.
Book chapter, Disinfection By-products in Drinking Water: Detection and Treatment, 2020, DOI Link
View abstract ⏷
The disinfection of drinking water is an integral component of water treatment in large volume, provides hygienically safe drinking water, and very essential worldwide. The interaction between the disinfectant agents and different dissolved components in water resultant in the formation of chemical substances categorized as disinfection by-products. The exposure to disinfection by-products and their potential toxic effects causes the occurrence of hazardous effects on human health. The levels of disinfection by-products in the drinking water strictly regulated due to their toxicity effects. This chapter is devoted to review, in brief, the recent reports on the various disinfection by-products and their associated toxicity effects. Furthermore, the approach of identification followed with controlling the disinfection by-products through different methods covering the broad aspects of conventional and recent ones will be covered.
Fenalan Yellow G adsorption using surface-functionalized green nanoceria: An insight into mechanism and statistical modelling
Rajarathinam N., Arunachalam T., Raja S., Selvasembian R.
Article, Environmental Research, 2020, DOI Link
View abstract ⏷
In the present study, green nanoceria (gNC) was synthesized and surface-functionalized (sf-gNC) with amine moieties through chemical means and used as an adsorbent for the removal of Fenalan Yellow G (FYG) from the aqueous solution. Prior to the adsorption process, the optical, structural and textural characteristics of the nanomaterial ensured the presence of highly crystalline and monodisperse nanoceria with the functionalized amine group on their surfaces. The effects of the independent variables of the FYG removal process including initial solution pH, adsorbent dose, initial adsorbate concentration and time were examined for the percent removal. The maximum removal of 93.62% was observed at the pH of 2.0 with the adsorbent dose of 0.1 g for 10 mg/L of FYG dye concentration in 210 min. The equilibrium studies revealed that the maximum adsorption capacity was 25.58 mg/g by monolayer Langmuir model at 303 K and the chemical kinetics results followed pseudo-second-order and chemisorptive Elovich model. The magnitude of the energy variables from the thermodynamic analysis exposed the feasibility and spontaneity of endothermic adsorption. Furthermore, the interactive effects of the screened process variables investigated and optimized through response surface methodology (RSM). Besides, the FYG adsorption behavior was well predicted using artificial neural network (ANN) model with good accuracy (Mean Squared Error < 0.5; Coefficient of determination > 0.99) using 3 input layers, 3 hidden layers and 1 output layer. The study proposed the intrinsic mechanism of adsorbent-adsorbate interactions as either of electrostatic interaction or through surface complexation. Moreover, the prepared amine-modified nanoceria was found to have a minimum of 75% regenerative potential for five adsorption-desorption cycles.
The role of sustainable decentralized technologies in wastewater treatment and reuse in subtropical Indian conditions
Ramprasad C., Rangabhashiyam S.
Book chapter, Water Conservation and Wastewater Treatment in BRICS Nations: Technologies, Challenges, Strategies and Policies, 2020, DOI Link
View abstract ⏷
Over the past two decades water demand has increased dramatically all over the world and scientists are focusing on finding alternative sources for water. Centralized treatment systems are uneconomical and inefficient in treating wastewater to reusable levels. Some studies hold that large centralized treatment systems are not a sustainable option for developing countries such as India, China, and South Africa. In India, systems that require more electricity fail to perform satisfactorily, as the power supply is intermittent and finds for operation and maintenance are not secure. Therefore, treating wastewater near its generation point and reusing it is a better solution. Policy makers are focusing on building decentralized treatment facilities in rural and peri-urban areas, with very few being built in urban area. Decentralized approaches aim not only at treating wastewater but also at providing benefits such as reusable water, energy efficiency, and nutrient recovery and reuse. However, the selection of technologies/management strategies depends upon the economic well-being of the community, the efficiency of the technology, social acceptance, and other factors. A matrix for decision-making in choosing the best technological option is essential and is included in this chapter. The two better-performing decentralized wastewater treatment systems for rural and urban India is also discussed in this chapter, along with the option chosen for reusing wastewater in an Indian textile manufacturing area.
A review of chromite mining in Sukinda Valley of India: impact and potential remediation measures
Nayak S., S R., P B., Kale P.
Review, International Journal of Phytoremediation, 2020, DOI Link
View abstract ⏷
Sukinda Valley, one of the highly polluted areas of the world is generating tons of mining waste and causing serious health and environmental issues in its surroundings. Several reports are available reporting the severity of hexavalent chromium, yet little efforts have been made to address the pollution and its remediation due to a lack of proper remedial measures. The review highlights the pros and cons of various physical, chemical and biological techniques used worldwide for the treatment of chromium waste and also suggests better and reliable bioremediation measures. Microbes such as Acidophilium and Acidithiobacillus caldus (Bioleaching), Pseudomonas, Micrococcus and Bacillus (Bioreduction), Aereobacterium and Saccharomyces (Biosorption), are widely used for bioremediation of hexavalent chromium owing to their unique metabolic activities, ionic movement through an extracellular membrane, and other cellular adsorptions and reduction properties. The use of native and hybrid combinations of microbes supported by organic supplements is projected as a fast and efficient technique that not only reduces chromium quantity but also maintains the integrity of the microbial sources. Innovation and emphasis on nano-based products like nanocomposite, nano adsorbent, nanoscale zerovalent iron (nZVI) particles and multifunctional plant-growth-promoting bacteria (PGPB) will serve as the next generation environmental remediation technologies in the near future.
Prediction of pyrolytic product composition and yield for various grass biomass feedstocks
Abhijeet P., Swagathnath G., Rangabhashiyam S., Asok Rajkumar M., Balasubramanian P.
Article, Biomass Conversion and Biorefinery, 2020, DOI Link
View abstract ⏷
Pyrolysis is the fundamental thermochemical reaction for both combustion and gasification processes aimed at the conversion of a wide array of biomass wastes into many desirable products. The main products of biomass pyrolysis are biochar, bio-oil, and flue gases (which includes methane, carbon monoxide, hydrogen, and carbon dioxide). The present article is an attempt to observe the effect of temperature on the pyrolysis process by using elementary composition of biomass to estimate the product yield along with its composition. This study considered the grasses such as bamboo, kenaf, miscanthus, reed canary, and switch grasses as the biomass feedstock. The dependence of pyrolytic product (solid, liquid, gas) formation on variation of temperature and heating rate has been discussed. The results revealed that the amount of pyrolytic product formation is dependent on the elementary and biochemical composition of grass biomasses. Based upon the biomass composition, possibility of co-pyrolysis has been discussed in this paper. Validation of model results revealed that almost 99% similarity is observed in the case of miscanthus biochar yield; however, 10% dissimilarity in gas and water yield for miscanthus is observed between predicted and experimental yield. This modeling approach would not only help in optimizing the pyrolysis process, but also encouraged the utilization of the biomass feedstock efficiently for the production of desired products in a sustainable manner.
The potential of lignocellulosic biomass precursors for biochar production: Performance, mechanism and wastewater application—A review
S R., P B.
Review, Industrial Crops and Products, 2019, DOI Link
View abstract ⏷
The organic and inorganic pollutants in water stream are due to the various industrial activities, consequent to the higher level environmental contamination. Considering the high toxicity and persistent property of wastewater pollutants, sequestration before discharge into water bodies becomes an important obligation. The conventional treatment methods are mostly associated with the drawbacks of energy intensive conditions and require high investment. Biochar produced through thermal decomposition of lignocellulosic biomass in the limited oxygen conditions offer as the sustainable potential adsorbent towards wastewater pollutants removal. The current review discusses on the utilization of various lignocellulosic biomass precursor for the production of biochar. The significant parameter influence and mechanistic aspects of the biochar production using pyrolysis were critically analyzed. The recent research on biochar modifications through different physical and chemical methods to enhance biochar adsorption property was reported. The new trend of the potential application of biochar in the adsorption of heavy metals, dyes and the underlying mechanisms are comprehensively reviewed. Further explorations are required in the directions of sustainable biochar development, continuous adsorption process, industry scale applications and spent biochar management.
Characteristics, performances, equilibrium and kinetic modeling aspects of heavy metal removal using algae
Rangabhashiyam S., Balasubramanian P.
Review, Bioresource Technology Reports, 2019, DOI Link
View abstract ⏷
Heavy metals from industrial effluent are major threat to environment because of their major toxicity effect. The treatment of metal contaminated wastewater is of special concern. This comprehensive review emphasis on the use of algae as the potential source of biosorbent, in this context variety of algae used by various researchers for the heavy metal biosorption is reviewed. The procedures for the biosorbent preparation, modification and their application towards the heavy metals were discussed. The effect of significant parameters in the metal biosorption process was presented. This review reports the biosorption isotherm and kinetic models, thermodynamic aspects of the metal biosorption by algae. The complex mechanisms of metal biosorption by algal presented along with the various instrumental techniques. It was evident from the literature survey that the algae demonstrated with excellent biosorption capabilities towards the removal of various toxic heavy metals.
Influence of biochar application on growth of Oryza sativa and its associated soil microbial ecology
Swagathnath G., Rangabhashiyam S., Murugan S., Balasubramanian P.
Article, Biomass Conversion and Biorefinery, 2019, DOI Link
View abstract ⏷
In this study, biochar was produced from three biomass feedstocks such as fruits of Cassia fistula and Caesalpinia sp. and barks of Eucalyptus globulus. The samples of the obtained biochar were characterized for pH, physiochemical properties, surface morphology, and surface functional groups. The obtained biochar samples were further studied with/without the combination of urea for their plant growth enhancement properties including the germination studies and effect on shoot and root growth of rice plants. Biochar produced from C. fistula fruits at 1.5% concentration increased the plant shoot height 18% higher than the control plants. Eucalyptus sp. barks’ biochar application at 0.5% concentration also increased the plant shoot height 12% longer than the control. However, the biochar produced from Caesalpinia sp. did not increase the shoot length. Yet, a generalized increase in root length was observed with the application of biochar. The combined application of nitrogen fertilizer (urea) and biochar together reverted the effect of biochar on the shoot length increase. Phospholipid-derived fatty acid (PLFA) characterization of soil revealed that soil biota shifts when soil was supplemented with the biochar. The bacterial community increased and a loss of fungal community was observed with the application of biochar.
Qualitative analysis of biodiesel produced by alkali catalyzed transesterification of waste cooking oil using different alcohols
Bunushree B., Ravichandra B., Rangabhashiyam S., Jayabalan R., Balasubramanian P.
Article, Indian Journal of Chemical Technology, 2019,
View abstract ⏷
The present study evaluates the nature of fatty acid methyl esters (FAMEs) formed through alkali-catalyzed transesterification of waste cooking oil (WCO) using methanol, ethanol as well as in combination, where the sequential addition of ethanol followed by methanol is done keeping the molar ratio of alcohol to oil constant (5:1), with sodium hydroxide as catalyst. A substantial reduction in reaction time from 8 h to 20 min is seen in the latter case. Further, the gas chromatography/mass spectrometry (GC-MS) analysis of the transesterified oil show a significant presence of FAMEs. Transesterified oil obtained from a combination of both the solvents show substantial quantities of unsaturated FAMEs [linoleic acids (41.89%), palmitelaidic acid (7.97%)], saturated FAMEs [stearic acids (4.62%), arachidic acids (2.54%)]and minor fraction of other acids. Hence, the utilization of WCO with the use of combined solvent system for transesterification, appear to have a great potential for replacing the conventional substrates that are being used for biodiesel production without much compromising on engine modifications.
Lanthanum‑iron binary oxide nanoparticles: As cost-effective fluoride adsorbent and oxygen gas sensor
Adithya G.T., Rangabhashiyam S., Sivasankari C.
Article, Microchemical Journal, 2019, DOI Link
View abstract ⏷
In the present work, novel lanthanum‑iron binary oxide nanoparticles are used as adsorbents for fluoride removal from aqueous solution and oxygen gas sensor. The lanthanum‑iron binary oxide nanoparticles were synthesized using co-precipitation method and sintered at a temperature of 100 °C, 450 °C, and 900 °C for 2 h. The material, optical and electrical properties of the nanoparticles were investigated by the instrumental characterization of high-resolution scanning electron microscope and high-resolution transition electron microscope to determine the structure, vibrating sample magnetometer which confirmed the superparamagnetic behavior, BET surface area analysis to affirm the mesoporous nature, X-ray photoelectron spectroscopy to confirm the oxidation states, X-ray diffraction, Fourier transform infrared spectroscopy, and I-V analysis, respectively. The adsorption of fluoride carried out in batch system, the experimental data were analyzed using isotherm and regeneration studies. The results demonstrated that the LIBONs sintered at 100 °C showed exceptional fluoride removal with maximum adsorption of 14.49 mg g −1 at pH 6.5 ± 0.5. The regeneration percentage of 80% was obtained after fifth cycle. The nanoparticles sintered at 900 °C rendered good sensitivity and response/recovery characteristics towards 50% of oxygen at operating temperature of 350 °C.
Assessment of hexavalent chromium biosorption using biodiesel extracted seeds of Jatropha sp., Ricinus sp. and Pongamia sp.
Rangabhashiyam S., Sayantani S., Balasubramanian P.
Article, International Journal of Environmental Science and Technology, 2019, DOI Link
View abstract ⏷
Abstract: Biosorbents from the biomass of Jatropha sp. (JES), Ricinus sp. (RES) and Pongamia sp. (PES) biodiesel extracted seeds were used in natural form for the elimination of hexavalent chromium. The study performed by varying the parameters of biosorbents size, solution pH, biosorbents dosage, metal concentration, contact time and temperature. The equilibrium data were correlated with two parameter isotherm models. Biosorption isotherm modeling showed that the biosorption data better explained by the Langmuir isotherm model with maximum monolayer biosorption capacities of 28.57, 19.60 and 27.77 mg/g for JES, RES and PES, respectively. The applicability of pseudo-second-order kinetics was observed in all the three biosorbents. The results of thermodynamic analysis showed that the biosorption of Cr(VI) ions onto JES, RES and PES was spontaneous in nature. Cr(VI)-loaded biosorbents were evaluated for a recycle studies with 0.1 M NaOH solution. Experiments conducted using Cr(VI) solution along with the coexisting ions demonstrated that the presence of co-ions slightly reduced the biosorption capacities of the JES and RES. Results of current research demonstrated that the JES, RES and PES could be used for the elimination of hexavalent chromium from aqueous system. Graphical Abstract: [Figure not available: see fulltext.].
Biosorption of Rhodamine B onto novel biosorbents from Kappaphycus alvarezii, Gracilaria salicornia and Gracilaria edulis
Selvakumar A., Rangabhashiyam S.
Article, Environmental Pollution, 2019, DOI Link
View abstract ⏷
First time reported biosorbents of Kappaphycus alvarezii, Gracilaria salicornia and Gracilaria edulis in native (KA, GS, GE) and ethanol modified (EKA, EGS, EGE) for Rhodamine B elimination from simulated system. In the present investigation seaweeds of macroalgae like Kappaphycus alvarezii, Gracilaria salicornia and Gracilaria edulis used as novel biosorbent in native (KA, GS, GE) and ethanol modified (EKA, EGS, EGE) for Rhodamine B (RB) removal from aqueous solution in batch process. Effect of various biosorption parameters such as pH, initial concentration of RB, biosorbent dosage and contact time were studied. The maximum biosorption capacity determined as 9.84 (KA), 11.03 (GS), 8.96 (GE), 112.35 (EKA), 105.26 (EGS) and 97.08 mg/g (EGE), respectively towards the removal of RB from aqueous solutions. Better removal of RB was observed using EKA, EGS, and EGE biosorbents at 2.0 pH. The characterizations of the biosorbents were performed using Scanning Electron microscope and Fourier Transform Infrared Spectroscopy. Biosorption equilibrium data evaluated using Langmuir, Freundlich, Temkin, Dubinin-Radushkevich and Jovanovic isotherm model. The Langmuir isotherm model best suited the equilibrium data for all the biosorbents studied. The rate of RB removal subjected to kinetic analysis using pseudo-first-order, pseudo-second-order, intra-particle diffusion and Elovich models. Pseudo-second-order kinetic model better described the experimental data of the RB biosorption. Desorption studies performed using 0.1 M sodium hydroxide as eluting agents for regeneration and recycle analysis. The recyclability of the six biosorbents showed consistent biosorption capacity towards RB removal up to the entire three cycles. The studied biosorbents sourced from large volume and easily available, further biosorption performance indicated that the KA, GS, GE, EKA, EGS and EGE could be used as efficient, alternative and eco-friendly biosorbents for the removal of harmful dyes in the environment.
Editorial: Emerging technologies for wastewater treatment and reuse
Krishnamoorthy S., Selvasembian R., Rajendran G., Raja S., Wintgens T.
Editorial, Water Science and Technology, 2019, DOI Link
Biosorption of Tm(III) by free and polysulfone-immobilized Turbinaria conoides biomass
Rangabhashiyam S., Vijayaraghavan K.
Article, Journal of Industrial and Engineering Chemistry, 2019, DOI Link
View abstract ⏷
The current investigation focus on the use of brown alga Turbinaria conoides (TC) and polysulfone immobilized Turbinaria conoides (PITC) for the biosorption of rare earth element Thulium (Tm(III)) from aqueous systems. To attain the highest removal of Tm(III), the process parameters including the equilibrium pH, Tm(III) concentration and biosorption time were optimized. The characterization techniques were used to analyse the morphological features and elemental analysis of the biosorbents. The isotherm models of selective two and three parameters were subjected to inspect the equilibrium data. The biosorption data fitted to the different biosorption kinetic models. Results illustrated that both TC and PITC displayed higher biosorption capacity of 200.5 and 157.9 mg/g, respectively. Through kinetic trials, we identified delay in equilibrium attainment for PITC and the data were described with intraparticle diffusion model. TC and PITC presented comparable results with biosorption equilibrium attained in 200 min, optimum equilibrium solution pH 5.0 and exhibited maximum biosorption capacity for the initial Tm(III) concentrations of 500 mg/L. Recovery studies represented that the maximum desorption efficiency attained using 0.01 M HCl and PITC presented potential uptake capacity of Tm(III) during the entire 10 biosorption–desorption cycles.
Adsorption behaviors of hazardous methylene blue and hexavalent chromium on novel materials derived from Pterospermum acerifolium shells
Rangabhashiyam S., Balasubramanian P.
Article, Journal of Molecular Liquids, 2018, DOI Link
View abstract ⏷
Heavy metal and dye are diffused pollutants in the wastewater, which impose a serious threat to the environment. Adsorption is the unconventional technique used for the sequestration of wastewater contaminants. Adsorbents prepared from Pterospermum acerifolium shells were successfully used for the first time for removing methylene blue and hexavalent chromium from aqueous solutions in a batch system. The effect of sulfuric acid, phosphoric acid treatments on Pterospermum acerifolium shells (SPAS, PPAS) and its native form (PAS) was investigated on the adsorption process. The influences of the solution pH (2.0–10.0), adsorbent dosage (0.01–0.1 g), initial MB, Cr(VI) concentrations (50–250 mg/L), and temperature (303−323 K) were examined for the removal process. Thermodynamic parameters were estimated for the thermodynamical modeling of the adsorption processes. Langmuir isotherm model better described the MB and Cr(VI) removal process. The maximum adsorption capacity achieved was 125 mg/g (PAS), 166.66 mg/g (SPAS), and 250 mg/g (PPAS) for MB removal and for Cr(VI) was 76.92 mg/g (PAS), 142.85 mg/g (SPAS), and 111.11 mg/g (PPAS), respectively. The experimental data as a function of contact time was modeled using the adsorption kinetic equations of pseudo-first order, pseudo-second order, Elovich and intra-particle diffusion models. The experimental adsorption data best correlated to pseudo-second order model. The shells of Pterospermum acerifolium are an efficient precursor for the preparation of adsorbents (PAS, SPAS, PPAS), successfully applied for the removal of methylene blue and hexavalent chromium from aqueous solutions.
Biosorption characteristics of methylene blue and malachite green from simulated wastewater onto Carica papaya wood biosorbent
Rangabhashiyam S., Lata S., Balasubramanian P.
Article, Surfaces and Interfaces, 2018, DOI Link
View abstract ⏷
The present study reports the sequestration of the cationic dyes, methylene blue (MB) and malachite green (MG) from aqueous solutions using natural Carica papaya wood (CPW) in a batch biosorption process. Characterizations of CPW were achieved by Field Emission Scanning Electron Microscopy, X-ray Diffractometer and Fourier transform infrared spectroscopy. The influence of various parameters such as solution pH, biosorbent dose, contact time, initial dye concentration and temperature were examined and optimal experimental conditions were determined. The biosorption isotherm models and kinetics characteristic of dye biosorption onto CPW were investigated. The equilibrium data followed the Langmuir isotherm model, predicted the maximum biosorption capacities of 32.25 and 52.63 mg dye per gram of CPW for MB and MG, respectively. The biosorption kinetics of MB and MG removal using CPW was better described by the pseudo-second-order kinetic equation. The experimental data obtained at different temperature of 303, 313 and 323 K for the biosorption of each dyestuff using CPW were analyzed through the thermodynamic parameters of ΔG° ΔH° and ΔS° respectively. Experiments on the regeneration studies indicated that the biosorption capacity of CPW was consistent towards MB and MG removal upto 5 recycles by subjecting 0.1 M HCl as the desorbing agent. The current investigation revealed that the simulated wastewater showed better removal of MB and MG under the studied experimental conditions. Hence, the biomass from Carica papaya wood could be employed as an efficient, eco-friendly and economical biosorbent for the removal of MB and MG from industrial wastewater.
Biosorption of hexavalent chromium and malachite green from aqueous effluents, using Cladophora sp
Rangabhashiyam S., Balasubramanian P.
Article, Chemistry and Ecology, 2018, DOI Link
View abstract ⏷
Biosorption potential of green macroalgae Cladophora sp., (GAC) for the removal of hexavalent chromium (Cr(VI)) and malachite green (MG) from aqueous medium was investigated. Optimal conditions for biosorption experiments were determined as a function of initial pH, GAC dosage, temperature and initial concentration of Cr(VI) and MG. The biosorption equilibrium data were fitted with the isotherm models of Langmuir, Freundlich, Kiselev, Frumkin and Jovanovic, while the experimental data were analysed using the kinetic models such as pseudo-first-order, pseudo-second-order, Ritchie's and intraparticle diffusion. The Langmuir maximum biosorption capacity was calculated as 100.00 mg/g (Cr(VI)) and 142.85 mg/g (MG). The biosorption kinetic data showed better agreement with the pseudo-second-order kinetic model. The thermodynamic parameters indicated spontaneous and endothermic nature of the biosorption process for Cr(VI) removal, whereas exothermic in the case of MG removal. Furthermore, the biosorption efficiencies of the GAC reusability were found significant up to five cycles and tested using 0.1, 0.5 and 1.0 M HCl, respectively. The results of the present study indicated that GAC is a suitable biosorbent for the sequestration of Cr(VI) and MG from aqueous solutions.
Utilization of unconventional lignocellulosic waste biomass for the biosorption of toxic triphenylmethane dye malachite green from aqueous solution
Selvasembian R., Balasubramanian P.
Article, International Journal of Phytoremediation, 2018, DOI Link
View abstract ⏷
Biosorption potential of novel lignocellulosic biosorbents Musa sp. peel (MSP) and Aegle marmelos shell (AMS) was investigated for the removal of toxic triphenylmethane dye malachite green (MG), from aqueous solution. Batch experiments were performed to study the biosorption characteristics of malachite green onto lignocellulosic biosorbents as a function of initial solution pH, initial malachite green concentration, biosorbents dosage, and temperature. Biosorption equilibrium data were fitted to two and three parameters isotherm models. Three-parameter isotherm models better described the equilibrium data. The maximum monolayer biosorption capacities obtained using the Langmuir model for MG removal using MSP and AMS was 47.61 and 18.86 mg/g, respectively. The biosorption kinetic data were analyzed using pseudo-first-order, pseudo-second-order, Elovich and intraparticle diffusion models. The pseudo-second-order kinetic model best fitted the experimental data, indicated the MG biosorption using MSP and AMS as chemisorption process. The removal of MG using AMS was found as highly dependent on the process temperature. The removal efficiency of MG showed declined effect at the higher concentrations of NaCl and CaCl2. The regeneration test of the biosorbents toward MG removal was successful up to three cycles.
Continuous biosorption assessment for the removal of hexavalent chromium from aqueous solutions using Strychnos nux vomica fruit shell
Nakkeeran E., Patra C., Shahnaz T., Rangabhashiyam S., Selvaraju N.
Article, Bioresource Technology Reports, 2018, DOI Link
View abstract ⏷
Column biosorption studies were performed to check the potential of Strychnos nux vomica tree fruit shell (STFS) towards Cr(VI) elimination from simulated aqueous solution. Effect of various parameters like height of bed (3, 5, 7 cm), flow rate inside the column (5, 10, 15 mL/min) and initial concentration of Cr(VI) in aqueous solution (50, 100, 150 mg/L) for removal of Cr(VI) were studied. The results revealed that Cr(VI) adsorption capacity (mg/g) marked up with the rise in bed height; decreased with elevation in flow rate and initial concentrations of Cr(VI). Biosorption column models viz. Adams-Bohart Thomas, Yoon-Nelson and Bed Depth Service Time (BDST) were evaluated with the equilibrium data. Comparatively, Thomas and BDST model presented better agreement with the equilibrium data. The current investigation verified STFS, a novel lignocellulosic biosorbent (STFS) which resulted in quite reasonable biosorption capacities could be used significantly for Cr(VI) removal from wastewater.
Novel adsorbent prepared from bio-hydrometallurgical leachate from waste printed circuit board used for the removal of methylene blue from aqueous solution
Nithya R., Sivasankari C., Thirunavukkarasu A., Selvasembian R.
Article, Microchemical Journal, 2018, DOI Link
View abstract ⏷
In the present study, the copper oxide nanoparticles (gCON) were synthesized from the extract of Prosopis juliflora (Sw.) leaves using copper nitrate, a leachate product of the waste printed circuit boards mediated through the bio-hydrometallurgical process. The synthesized gCON was characterized through the UV–Vis, Raman, FT-IR, zeta potential, XRD, BET model and SEM. Methylene blue (MB) adsorption onto gCON tested in batch trials by varying the pH, initial adsorbate concentration and contact time. The chemical kinetics of MB adsorption followed the pseudo-second-order and chemisorptive Elovich models with a high degree of linearity (r2 > 0.99) and marginal error values. Further, the isotherm data suggested the monolayer coverage of MB as the experimental data aligns well with the Langmuir model (r2 > 0.99) and the maximum dye adsorption capacity (qm) of gCON was computed as 163.93 mg/g. The magnitude of thermodynamic functions identified the chemisorptive removal of MB as spontaneous and endothermic. The mass transfer analysis verified that both intra-particle and liquid film diffusion limits the adsorption process. Desorption results showed that gCON can be regenerated for a maximum of three cycles. The present study demonstrated that gCON can be used as an unconventional adsorbent for the removal of MB from aqueous solutions.
Performance of novel biosorbents prepared using native and NaOH treated Peltophorum pterocarpum fruit shells for the removal of malachite green
Rangabhashiyam S., Balasubramanian P.
Article, Bioresource Technology Reports, 2018, DOI Link
View abstract ⏷
The Peltophorum pterocarpum fruit shells were treated with sodium hydroxide, employed for the malachite green biosorption. Biosorbents characterization conducted using the Environmental Scanning Electron Microscopy and X-ray Diffractometer. The MG removal performance was evaluated in a batch biosorption system by varying the process parameters. The biosorption data modeled using the Langmuir, Freundlich, Tempkin, Halsey and Jovanovic isotherm models. The Langmuir model superior explained the equilibrium data among the isotherms considered in the current investigation. The maximum uptake capacity of 62.50 mg/g was observed for sodium hydroxide treated biomass, whereas native biosorbent showed 40.00 mg/g. The kinetic modeling of the experimental data revealed that the better fit of the pseudo-second-order kinetic model and suggested the mechanism of chemisorption. MG biosorption using sodium hydroxide treated biomass of enthalpy with positive values indicates endothermic and Gibbs free energy of negative values represented spontaneous nature.
Assessment of samarium biosorption from aqueous solution by brown macroalga Turbinaria conoides
Vijayaraghavan K., Rangabhashiyam S., Ashokkumar T., Arockiaraj J.
Article, Journal of the Taiwan Institute of Chemical Engineers, 2017, DOI Link
View abstract ⏷
In the present research, a brown marine macroalga (Turbinaria conoides) was employed as a novel biosorbent for the sequestration of samarium ions from aqueous solutions. The influence of solution pH, initial Sm(III) concentration and contact time on Sm(III) removal were investigated. The biosorbent was characterized through Fourier transform infrared spectroscopy, potentiometric titration, scanning electron microscopy and energy-dispersive X-ray spectroscopy analysis. Equilibrium experimental results were fitted to isotherm models such as the Langmuir, Freundlich and Redlich–Peterson to obtain the characteristic parameters of each model. The pseudo-first-order and pseudo-second-order kinetic models were used to analyze the experimental kinetic data. The Langmuir and Redlich–Peterson isotherms were found to best fit the equilibrium data and the biosorption kinetics followed the pseudo-second-order model. From the Langmuir isotherm model, the maximum biosorption capacity was found to be 151.6 mg/g at the solution pH 4.0. Desorption experiments revealed that 0.1 M HCl was efficient with good recovery of Sm(III) ions with desorption efficiency of 99.2%.
Equilibrium and kinetics studies of hexavalent chromium biosorption on a novel green macroalgae Enteromorpha sp.
Rangabhashiyam S., Suganya E., Lity A.V., Selvaraju N.
Article, Research on Chemical Intermediates, 2016, DOI Link
View abstract ⏷
This study focuses on the use of novel Enteromorpha sp. macroalgal biomass (EMAB), for the biosorption of hexavalent chromium from aqueous solutions. The biosorbent was characterized by Fourier transformer infrared spectroscopy, energy dispersive spectroscopy, and scanning electron microscopy techniques. The effect of experimental parameters such as pH, initial concentration of Cr(VI) ions, biosorbent dosage, and temperature were evaluated. The maximum biosorption capacity for Cr(VI) was observed at pH 2.0. The modeling of the experimental data at equilibrium was performed using two parameter isotherm models. Both Langmuir and Freundlich isotherm equations better fitted the equilibrium data. A contact time of different initial Cr(VI) concentrations was about 160 min to attain biosorption equilibrium. The kinetic data were fitted by models including pseudo-first-order, pseudo-second-order, and intraparticle diffusion. The pseudo-second-order and intraparticle diffusion kinetic models adequately described the kinetic data. Moreover, the thermodynamic parameters indicated that the biosorption process was spontaneous, endothermic, and increased randomness in nature. The results showed that EMAB could be used as an effective biosorbent for the removal of Cr(VI) from aqueous solution.
Packed bed column investigation on hexavalent chromium adsorption using activated carbon prepared from Swietenia Mahogani fruit shells
Rangabhashiyam S., Suganya E., Selvaraju N.
Article, Desalination and Water Treatment, 2016, DOI Link
View abstract ⏷
The removal of Cr(VI) from aqueous solution by a novel Swietenia Mahogani fruit shell physically activated carbon (SMFS-PAC) was examined in a packed bed column study. The effects of significant parameters such as feed flow rate, bed depth, and initial Cr(VI) concentration were studied. Column data obtained at different conditions were described using the Thomas, Bed depth service time (BDST), Adams–Bohart, and Yoon–Nelson model in order to predict the breakthrough curves and to evaluate the model parameters of the packed bed column studies data. Among the models used, Thomas, BDST, and Yoon–Nelson model, respectively, fitted to the experimental data very well. The SMFS-PAC column study states the value of the good adsorption capacity for the removal of Cr(VI) from aqueous solution.
Adsorption of hexavalent chromium from synthetic and electroplating effluent on chemically modified Swietenia mahagoni shell in a packed bed column
Rangabhashiyam S., Nandagopal M.S.G., Nakkeeran E., Selvaraju N.
Article, Environmental Monitoring and Assessment, 2016, DOI Link
View abstract ⏷
Packed bed column studies were carried out to evaluate the performance of chemically modified adsorbents for the sequestration of hexavalent chromium from synthetic and electroplating industrial effluent. The effects of parameters such as bed height (3–9 cm), inlet flow rate (5–15 mL/min), and influent Cr(VI) concentration (50–200 mg/L) on the percentage removal of Cr(VI) and the adsorption capacity of the adsorbents in a packed bed column were investigated. The breakthrough time increased with increasing bed height and decreased with the increase of inlet flow rate and influent Cr(VI) concentration. The adsorption column models such as Thomas, Adams–Bohart, Yoon–Nelson, and bed depth service time (BDST) were successfully correlated with the experimental data. The Yoon–Nelson and BDST model showed good agreement with the experimental data for all the studied parameter conditions. Results of the present study indicated that the chemically modified Swietenia mahagoni shell can be used as an adsorbent for the removal of Cr(VI) from industrial wastewater in a packed bed column.
Hydrous Cerium Oxide Nanoparticles Impregnated Enteromorpha sp. for the Removal of Hexavalent Chromium from Aqueous Solutions
Rangabhashiyam S., Selvaraju N., Raj Mohan B., Muhammed Anzil P.K., Amith K.D., Ushakumary E.R.
Article, Journal of Environmental Engineering (United States), 2016, DOI Link
View abstract ⏷
A novel nanobiocomposite, hydrous cerium oxide nanoparticles impregnated Enteromorpha sp. (HCONIE) was used effectively for the adsorption of Cr(VI) from aqueous solutions. The chemical and structural characteristics of the nanobiocomposite were investigated using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) analysis. Adsorption studies were determined as a function of pH, contact time, initial concentration of Cr(VI), HCONIE dose, and temperature. The equilibrium adsorption data were modeled using two parameter isotherms, including Langmuir, Freundlich, Dubinin-Radushkevich (D-R), Temkin, Jovanovic, Halsey, and Harkin-Jura. Adsorption data were well described by the Freundlich and Halsey isotherm. The kinetics data were analyzed using adsorption kinetic models like the pseudo-first-order, pseudo-second-order and intraparticle diffusion equation. Kinetic data showed good agreement with the pseudo-second-order kinetic model. The obtained thermodynamic parameters showed that the adsorption of Cr(VI) onto the HCONIE was exothermic in nature. The presence of foreign ions showed a decreased effect on the adsorption capacity of HCONIE towards Cr(VI) removal. The desorption study was carried out with 0.1 and 0.5 M of three different desorbing agents. The study suggests that HCONIE nanobiocomposite could be used for the removal of Cr(VI) from aqueous solution.
Removal of hexavalent chromium from aqueous solution by a novel biosorbent Caryota urens seeds: equilibrium and kinetic studies
Suganya E., Rangabhashiyam S., Lity A.V., Selvaraju N.
Article, Desalination and Water Treatment, 2016, DOI Link
View abstract ⏷
A novel biosorbent Caryota urens seeds (CUS) was investigated for the technical feasibility for the biosorption of hexavalent chromium from aqueous solution. The biosorbent was characterized by SEM, FT-IR spectral, and EDS analysis. Effects of biosorbent size, biosorbent dosage, Cr(VI) concentration, pH, and contact time on the biosorption of hexavalent chromium were investigated. Both the Langmuir and Freundlich isotherms were suitable for describing the biosorption of Cr(VI) onto CUS. Application of the Langmuir isotherm model to the biosorption system yielded a maximum biosorption capacity of 52.63 mg/g at an equilibrium pH value of 2 and 303 K. Kinetic data were best fitted with the pseudo-second-order kinetic model. The results indicate that the CUS can be effective biosorbent for the removal of Cr(VI) from aqueous solution.
Use of Box–Behnken design of experiments for the adsorption of chromium using immobilized macroalgae
Rangabhashiyam S., Giri Nandagopal M.S., Nakkeeran E., Keerthi R., Selvaraju N.
Article, Desalination and Water Treatment, 2016, DOI Link
View abstract ⏷
Optimization experiments were carried using three-level Box–Behnken design for the adsorption of chromium onto immobilized macroalgae. The influence of independent parameters such as pH (2−8), temperature (303−333 K), and initial chromium concentration (20−100 mg/L) towards chromium ions removal has been performed. Second-order polynomial models were developed for the responses. The significance of the independent parameters and their interactions were investigated using the analysis of variance. The three-dimensional (3-D) response surface plots were used to study the interactive effects of the independent parameters on the chromium removal efficiency. The maximum Cr(VI) removal efficiency of 90.52, 90.86 was observed for Enteromorpha sp. immobilized in sodium alginate (ESA), Enteromorpha sp. immobilized in polysulfone (EPS), and maximum observed total chromium removal efficiency of 81.14, 79.90 was obtained for ESA, EPS, respectively. The observed value was in good agreement with the predicted values. These results indicated that immobilized macroalgae could be used for the removal of chromium from aqueous solution.
Removal of Cr(VI) from aqueous solution using Strychnos nux-vomica shell as an adsorbent
Nakkeeran E., Rangabhashiyam S., Giri Nandagopal M.S., Selvaraju N.
Article, Desalination and Water Treatment, 2016, DOI Link
View abstract ⏷
In the present study, the removal of Cr(VI) from aqueous solution by a Strychnos nux-vomica shell was examined in a batch study. The main process parameters such as adsorbent dose, pH, initial concentration, temperature, agitation speed and contact time were studied. The result shows that the maximum removal of Cr(VI) was observed at pH 2. The progressive changes on surface texture and the confirmation of chromium binding on adsorbent surface at different stages were obtained by the scanning electron microscopy, energy-dispersive X-ray spectroscopy and Fourier transform infrared spectrometer analysis. The equilibrium data from the biosorption study was evaluated by the use of two parameter isotherm models. Langmuir isotherm model seems to fit better with the equilibrium data. Kinetic studies were performed using pseudo-first-order, pseudo-second-order and intraparticle diffusion models. The biosorption data were found to best fitted for pseudo-second-order kinetic model. The calculated thermodynamic parameters such as ΔG°, ΔH° and ΔS° showed that the adsorption of Cr(VI) ions onto adsorbents was spontaneous, endothermic and increased randomness in nature. The results indicate that STFS can be an effective adsorbent for the removal of Cr(VI) from aqueous solutions.
Mono- and multi-component biosorption of lead(II), cadmium(II), copper(II) and nickel(II) ions onto coco-peat biomass
Vijayaraghavan K., Rangabhashiyam S., Ashokkumar T., Arockiaraj J.
Article, Separation Science and Technology (Philadelphia), 2016, DOI Link
View abstract ⏷
The potential of using coco-peat biomass (CPB) has been assessed for the removal of Pb(II), Cd(II), Cu(II) and Ni(II) ions from single and quaternary solutions. According to Langmuir isotherm, the maximum biosorption capacity of CPB was 0.484, 0.151, 0.383 and 0.181 mmol/g for Pb(II), Cd(II), Cu(II) and Ni(II) ions, respectively. Scanning electron microscopy along with energy-dispersive X-ray spectroscopy and Fourier-transform IR spectroscopy confirmed changes in the biosorbent functionality after metal sorption. Through quaternary isotherm experiments, 16.1%, 48.2%, 32.3% and 46.5% decrease in experimental uptakes were observed for Pb(II), Cd(II), Cu(II) and Ni(II), respectively, in the presence of other metal ions.
Optimization of gac supported TiO2 photocatalytic process for competent carbofuran removal from an aqueous system
Vishnuganth M.A., Rangabhashiyam S., Remya N., Kumar M., Selvaraju N.
Article, Journal of Scientific and Industrial Research, 2015,
View abstract ⏷
The present study employed central composite design (CCD) and response surface methodology (RSM) to evaluate the carbofuran removal by photo catalytic process. The carbofuran removal process was carried out in a batch reactor with granular activated carbon (GAC) supported TiO2 (GAC-TiO2) as the photo catalyst. The influence of operating parameters such as initial carbofuran concentration, TiO2 concentration and pH was modelled using CCD and RSM with 11 experimental runs. In the experimental runs, the carbofuran concentration was carried from 1 to 250 mg L-1, TiO2 concentration was ranged from 5 to 75 mg L-1 and pH was varied from 3-11. The experimental outcomes from CCD revealed an increased carbofuran removal with increase in pH. Complete removal of carbofuran was observed within 240 min in all the runs except in those with higher carbofuran concentration (i.e., 250 mg L-1) and lower pH (i.e., 3). Furthermore, Polynomial equations were developed to predict the carbofuran removal under different operating conditions. The result indicated that the carbofuran concentraration and pH as well as the interaction term of TiO2 concentration and pH had significant effect on the removal process. Good correlation between observed and predicted values indicated that the developed model can be used to predict the carbofuran removal under different operating conditions within the range that is analysed in this particular study. The optimum conditions for carbofuran removal were observed for a carbofuran concentration of 50 mg L-1, TiO2 concentration of 5 mg L-1 and pH 7.9. These observations revealed that the carbofuran removal was probably due to the adsorption of carbofuran on the GAC surface and subsequent accelerated degradation of carbofuran on the GAC/GAC-TiO2 surface. Therefore, the adsorbent medium and the adsorbent supported catalyst could be effectively used for efficient treatment of carbofuran contaminated water in a batch-mode photocatalysis system.
Evaluation of optimization methods for solving the receptor model for chemical mass balance
Anu N., Rangabhashiyam S., Rahul A., Selvaraju N.
Article, Journal of the Serbian Chemical Society, 2015, DOI Link
View abstract ⏷
The chemical mass balance (CMB 8.2) model has been extensively used in order to determine source contribution for particulate matters (size diameters less than 10 and 2.5 μm) in air quality analysis. A comparison of the source contribution estimated from three CMB models was realized through optimization techniques, such as 'fmincon' (CMB-fmincon) and genetic algorithm (CMB-GA) using MATLAB. The proposed approach was validated using a San Joaquin Valley Air Quality Study (SJVAQS) California Fresno and Bakersfield PM10 and PM2.5 followed with Oregon PM10 data. The source contribution estimated from CMB-GA was better in source interpretation in comparison with CMB 8.2 and CMB-fmincon. The performance accuracies of three CMB approaches were validated using R2, reduced X2 and percentage mass tests. The R2 (0.90, 0.67 and 0.81, 0.83), X2 (0.36, 0.66 and 0.65, 0.43) and percentage mass (67.36, 55.03 and 94.24 %, 74.85 %) of CMB-GA showed high correlation for PM10, PM2.5, Fresno and Bakersfield data, respectively. To make a complete decision, the proposed methodology was bench marked with Portland, Oregon PM10 data with the best fit with R2 (0.99), X2 (1.6) and percentage mass (94.4 %) from CMB-GA. Therefore, the study revealed that CMB with genetic algorithm optimization method exhibiting better stability in determining the source contributions.
Screening of functional groups, dna quantification and determination of antimicrobial potency of corallocarpus epigaeus tubers
Saranya N., Rangabhashiyam S., Rubini D., Sivaranjani C.R.
Article, International Journal of Pharmaceutical and Clinical Research, 2015,
View abstract ⏷
This is most probably the first work in isolating genomic DNA from the dried tubers of Corallocarpus epigaeus (Ce), which is a medicinal plant, belongs to the family Cucurbitaceae using Cetyl Trimethyl Ammonium Bromide extraction method. Ultraviolet spectroscopy is done for the quantitative determination of DNA isolated. Antimicrobial activity of Corallocarpus epigaeus is checked for microbes Salomonella typhi, Streptococcus luteus, Klebsiella, Aspergillus niger using the extract prepared from dried tuber with ethanol and benzene and the zone of inhibition was measured. Minimum inhibitory concentration for specific microbes has been determined. Preliminary Phytochemical screening was done to determine the constituents present in the tuber. Fourier transform infrared spectroscopy technique is performed to determine the functional groups present in the tuber. The results revealed the presence of important antimicrobials and also support the continued sustainable use of these plants in traditional systems of medicine.
Adsorptive remediation of hexavalent chromium from synthetic wastewater by a natural and ZnCl2 activated Sterculia guttata shell
Rangabhashiyam S., Selvaraju N.
Article, Journal of Molecular Liquids, 2015, DOI Link
View abstract ⏷
The present study deals with the removal of Cr(VI) ions from aqueous solutions by raw Sterculia guttata shell waste (RSGS) and ZnCl2 activated S. guttata shell waste (ASGS). Effect of various process parameters like solution pH, adsorbent dose, initial Cr(VI) concentration and temperature has been studied in batch system. The experimental data were fitted to the isotherm models. Langmuir isotherm model best fitted the adsorption equilibrium data and the adsorption capacity of RSGS and ASGS was found as 45.45 and 90.90 mg/g respectively at 2.0 pH. The data were analyzed on the basis of pseudo-first-order, pseudo-second-order, intra-particle diffusion and Boyd models. Higher degree of coefficient of determination was obtained for the pseudo-second-order kinetic model. The calculated thermodynamic parameters such as ΔG°, ΔH°and ΔS°showed that the adsorption of Cr(VI) ions onto adsorbents was spontaneous, endothermic and increased randomness in nature. Desorption study was carried out with different concentrations of NaOH solutions. The results of the present study suggested that RSGS and ASGS can be used beneficially in treating industrial effluents containing hexavalent chromium.
Evaluation of the biosorption potential of a novel Caryota urens inflorescence waste biomass for the removal of hexavalent chromium from aqueous solutions
Rangabhashiyam S., Selvaraju N.
Article, Journal of the Taiwan Institute of Chemical Engineers, 2015, DOI Link
View abstract ⏷
The present study was undertaken in order to evaluate the feasibility of a novel biosorbent Caryota urens inflorescence waste biomass (CUIWB) for the removal of hexavalent chromium from aqueous solutions. The biosorbent was characterized by SEM, FT-IR spectral and EDS analysis. Biosorption studies were carried out as a function of pH, initial Cr(VI) concentration, biosorbent size, biosorbent dosage, agitation speed and temperature. It was found that the biosorption capacity of CUIWB depends on solution pH, maximum biosorption capacity for Cr(VI) was observed at pH 2. The isotherm models like Langmuir, Freundlich, Dubinin-Radushkevich, Elovich, Redlich-Peterson, Sips, Koble-Corrigan were used to analyze the equilibrium data. Langmuir and Redlich-Peterson model better fitted the equilibrium data. The biosorption capacity obtained using Langmuir isotherms for Cr(VI) biosorption was 100. mg/g. Kinetic study was performed using pseudo-first-order, pseudo-second-order and intraparticle diffusion models, but higher degree of coefficient of determination was obtained for the pseudo-second-order kinetic model. Different thermodynamic parameters, viz., δ. G°, δ. H° and δ. S° have also been evaluated and it has been found that the biosorption was spontaneous at low Cr(VI) concentration (100 and 200. mg/L), endothermic and increased randomness in nature, respectively. Desorption study was carried out with 0.1. M NaOH solutions. Investigations carried out proved that CUIWB is a good potential biosorbent for the treatment of hexavalent chromium in aqueous media.
Dynamic adsorption modeling study using a modified Redilch-Peterson isotherm model
Suganya E., Rangabhashiyam S., Varghese L.A., Selvaraju N.
Article, Journal of Scientific and Industrial Research, 2015,
View abstract ⏷
The untreated grey water generated by domestic activities is the major sanitation problem. From the industrial point of view, the modeling approach of three parameter isotherm model Redilch-Peterson based on the column system has been considered. A theoretical one dimension dynamic model was proposed to understand the behaviour in fixed bed, assuming Straight run mode to study the phenomenon of adsorption. Using MATLAB linear programming and least square method the parameters involved have been optimized. Thus predicted results are correlated with the theory and experimental observation available in the literature using Mathematical derivation and MATLAB. Thus a modified Redilch-Peterson isotherm model in packed bed for waste water treatment has been proposed.
Optimization of wind speed on dispersion of pollutants using coupled receptor and dispersion model
Anu N., Rangabhashiyam S., Antony R., Selvaraju N.
Article, Sadhana - Academy Proceedings in Engineering Sciences, 2015, DOI Link
View abstract ⏷
Air pollutants emission from various source categories can be quantified through mass balance (receptor model) techniques, multivariate data analysis and dispersion model. The composition of particulate matter from various emission points (emission inventory) and the massive analysis of the composition in the collected samples from various locations (receptor) are used to estimate quantitative source contribution through receptor models. In dispersion model, on the other hand the emission rates (μg/m3) from various sources together with particle size, stack height, topography, meteorological conditions (temperature, humidity, wind speed and directions, etc.) will affect the pollutant concentration at a point or in a region. The parameters used in dispersion model are not considering in receptor models but have been affecting indirectly as difference concentration at various receptor locations. These differences are attributed and possible erroneous results can be viewed through coupled receptor-dispersion model analysis. The current research work proposed a coupled receptor-dispersion model to reduce the difference between predicted concentrations through optimized wind velocity used in dispersion model. The converged wind velocities for various error percentages (10%, 40%, 60% and 80%) in receptor concentration have been obtained with corresponding increase in the error. The proposed combined approaches help to reconcile the differences arise when the two models used in an individual mode.
Efficacy of unmodified and chemically modified Swietenia mahagoni shells for the removal of hexavalent chromium from simulated wastewater
Rangabhashiyam S., Selvaraju N.
Article, Journal of Molecular Liquids, 2015, DOI Link
View abstract ⏷
The shell of Swietenia mahagoni was modified using sulfuric acid and ortho-phosphoric acid to improve the adsorption capacity for the removal of hexavalent chromium from aqueous solutions. The adsorbent characterization was done by using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and thermogravimetric analysis (TGA). The adsorption of Cr(VI) using RSMS, SSMS and PSMS was investigated as a function of solution pH, adsorbent dosage, contact time, initial metal concentration and temperature in batch studies. The adsorption equilibrium data were well studied for adsorption isotherm models, kinetic models and thermodynamics. The adsorption data better followed the Langmuir model rather than the other models studied. An appreciable increase in the adsorption capacities of SSMS (47.61 mg/g) and PSMS (58.82 mg/g), was observed compared to RSMS (37.03 mg/g). The adsorption kinetic data were best described by a pseudo-second-order kinetic model. Thermodynamic parameters revealed the spontaneous, endothermic and increased randomness nature of the Cr(VI) adsorption process. Desorption analysis was performed with 0.1, 0.5 and 1 M concentrations of NaOH solutions. The results of the present study illustrated that RSMS, SSMS and PSMS can be used as effective adsorbents for the removal of hexavalent chromium from an aqueous system.
Biosorption potential of a novel powder, prepared from Ficus auriculata leaves, for sequestration of hexavalent chromium from aqueous solutions
Rangabhashiyam S., Nakkeeran E., Anu N., Selvaraju N.
Article, Research on Chemical Intermediates, 2015, DOI Link
View abstract ⏷
A novel biosorbent, powdered Ficus auriculata leaves (FALP), has been used to remove hexavalent chromium from aqueous solutions by use of a batch technique. The biosorbent was characterized by surface area analysis, Fourier-transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. The effects on adsorption of pH, initial Cr(VI) ion concentration, amount of FALP, agitation speed, and temperature were investigated. Equilibrium data from the biosorption study were evaluated by use of two and three-variable isotherm models. The equilibrium data were better fitted by use of a three-variable isotherm model. The kinetics of biosorption were examined by use of pseudo-first-order and pseudo-second-order kinetic models and an intraparticle diffusion model. The biosorption data were best fit by the pseudo-second-order kinetic model. Thermodynamic investigation revealed that biosorption of hexavalent chromium ions by FALP is spontaneous in nature, endothermic, and results in increased randomness. The study suggests that FALP could be used as a potential biosorbent for removal of hexavalent chromium from wastewaters.
Invitro antimicrobial activity, DNA sequencing and phytochemical screening of A medicinal plant- Ruellia patula Jacq
Saranya N., Sumathra P., Rangabhashiyam S., Elangomadhavan R., Suman P.
Article, International Journal of Pharmacognosy and Phytochemical Research, 2014,
View abstract ⏷
RuelliapatulaJacq (syn: Dipteracanthus patulus) belongs to the family Acanthaceae, has numerous medicinal properties but is not exploited much in modern medicine. Invitro antimicrobial activity of the Ruelliapatulajacq leaves extracted with Ethanol, Methanol and Acetone was checked for Bacillus subtilis, Escherichia coli and Aspergillus niger by disc diffusion method. Ethanol was found to be the better solvent that its extract showed more activity against Aspergillus niger, Escherichia coli and Bacillus subtilis respectively. Preliminary phytochemical screening of ethanolic and methanolic extracts showed positive results for alkaloids, steroids, phenols, flavonoids, tannins and terpenoids. Genomic DNA was extracted from RuelliapatulaJacq leaves using the standard Cetyl Trimethyl Ammonium Bromide extraction method. The DNA extracted responded well during PCR amplification and RAPD analysis with three gene specific primers and five random Medicinal aromatic plant primers respectively. Chromatographic fingerprinting of the ethanolic extract of the plant leaves was analyzed for compounds present in the sample using analytical type HPLC using a C-13 Column and a UV- detector of the RuelliapatulaJacq for the detection of the chemical constituents in the plant. Analytical type chromatogram revealed the presence of 8 compounds in the extract under scanning at 205 nm. The preparative type HPLC chromatogram revealed the presence of 2 major compounds in the extract. The collected fractions were subjected to FT-IR spectroscopy and UV-Visible spectrum analysis. FT-IR Spectrum studies on RuelliapatulaJacq ethanolic extract showed the possibility of harbouring secondary metabolites with higher pharmaceutical value.
Overview of microneedle system: A third generation transdermal drug delivery approach
Giri Nandagopal M.S., Antony R., Rangabhashiyam S., Sreekumar N., Selvaraju N.
Review, Microsystem Technologies, 2014, DOI Link
View abstract ⏷
Transdermal drug delivery has given cardinal contribution to medical practices. First-generation transdermal delivery of small, lipophilic, low-dose drugs and second-generation delivery systems using chemical enhancers, non-cavitational ultrasound and iontophoresis have also resulted in various clinical products provides added functionality. Third-generation delivery systems using microneedles, thermal ablation, microdermabrasion, electroporation and cavitational ultrasound targeting skin's barrier layer of stratum corneum. Microneedles acquire pronounced intrigue in recent days. Currently, microneedles are advancing through clinical trials for delivery of macromolecules and vaccines, such as insulin, parathyroid hormone and influenza vaccine. The review explains about the concept of transdermal drug microneedle system comprising of microreservoir, micropumps, flow sensors, types of microneedles. Various researches carried out on these components of microneedle system is elaborately discussed in this review. © 2014 Springer-Verlag Berlin Heidelberg.
Evaluation of optimization methods for solving chemical mass balance receptor model
Anu N., Rangabhashiyam S., Rahul A., Selvaraju N.
Article, Journal of the Serbian Chemical Society, 2014, DOI Link
View abstract ⏷
Balance (CMB) model has been extensively used in order to determine source contribution for particulate matters (size diameters less than 10 μ m and 2.5 μ m) in the air quality analysis. A comparison of the source contribution estimated from the three CMB models (CMB 8.2, CMB-fmincon and CMB-GA) have been carried out through optimization techniques such as 'fmincon' (CMB-fmincon) and genetic algorithm (CMB-GA) using MATLAB. The proposed approach has been validated using San Joaquin Valley Air Quality Study (SJVAQS) California Fresno and Bakersfield PM10 and PM25 followed with Oregon PM10 data. The source contribution estimated from CMB-GA was better in source interpretation in comparison with CMB8.2 and CMB-fmincon. The performance accuracy of three CMB approaches were validated using R-square, reduced chi-square and percentage mass tests. The R-square (0.90, 0.67 and 0.81, 0.83), Chi-square (0.36, 0.66 and 0.65, 0.43) and percentage mass (67.36 %, 55.03 % and 94.24 %, 74.85 %) of CMB-GA showed high correlation for PM10, PM25 Fresno and Bakersfield data respectively. To make a complete decision, the proposed methodology has been bench marked with Portland, Oregon PM10 data with best fit with R2 (0.99), Chi-square (1.6) and percentage mass (94.4 %) from CMB-GA. Therefore, the study revealed that CMB with genetic algorithm optimization method holds better stability in determining the source contributions.
A Novel approach of the modified BET isotherm towards continuous column study
Rangabhashiyam S., Anu N., Giri Nangagopal M.S., Selvaraju N.
Article, Journal of Scientific and Industrial Research, 2014,
View abstract ⏷
Adsorption can be used to treat wastewater containing pollutants even at the low concentration in a very effective manner. The significance of the Langmuir, Brunauer Emmet Teller Isotherm was investigated for the perfect correlation with the experimental data. A theoretical one dimension dynamic model was proposed to understand the behavior of fixed bed with the assumption of straight through run mode of operation. The limitations associated with the application of classical Brunauer Emmet Teller to the liquid phase modeling were represented. The results were correlated using the theory and experimental observation available in the recently published literature through Mathematical derivation and MATLAB. The present study reveals that the modified Brunauer Emmet Teller isotherm posses the potential towards the applicability as Monolayer Langmuir adsorption isotherm under the condition of number of layer is equal to one.
Relevance of isotherm models in biosorption of pollutants by agricultural byproducts
Rangabhashiyam S., Anu N., Giri Nandagopal M.S., Selvaraju N.
Review, Journal of Environmental Chemical Engineering, 2014, DOI Link
View abstract ⏷
Industries generating wastewater with elevated concentrations of pollutants (e.g. metals, dyes, phenolic compounds, anions, etc.) need specialized atreatment systems. Adsorption is one of the most extensively applied techniques for the removal of pollutants from the industrial effluents. The prominent and emerging trend of subjecting biosorbent in the adsorption technology is mainly because of their natural existence, abundance, renewable, biodegradable and economic features. The adsorption isotherm equations used to describe the experimental data and the thermodynamic assumptions of the models often provide some insight into the sorption mechanism, the surface properties and affinity of the biosorbent. This paper presents a state of the art on the review of adsorption isotherm models in an exhaustive manner on the basis of two, three, four and five parameters respectively. Focuses on the various sources of agricultural byproducts as biosorbents and describes on the potential applications of different adsorption isotherm models for the evaluation of the wastewater pollutants biosorption. It is evident from the literature survey that various adsorption isotherm models have been considered under study by the researchers but mostly two and three parameter isotherm model were best fitted the equilibrium data. This paper reviews the adsorption isotherm models on the basis of parameters that can be applied for exploring a novel biosorbents. © 2014 Elsevier Ltd. All rights reserved.
Probabilistic Neural Network prediction of liquid- liquid two phase flows in a circular microchannel
Antony R., Nandagopal M.S.G., Rangabhashiyam S., Selvaraju N.
Article, Journal of Scientific and Industrial Research, 2014,
View abstract ⏷
The present work proposes towards flow pattern prediction in a liquid- liquid microchannel flow through a circular channel. Mass transfer in a microchannel mainly depends on the flow regime inside the channel. The liquid-liquid two phase flow regime in a microchannel depends on the flow velocity and the junction characteristics. Hence, the prediction of patterns has a superior role for the characterisation of mass transfer rates. This paper experimentally investigates the flow pattern in an 800 micro meter diameter microchannel with T junction. The slug length variation corresponding to varying inlet flow rate for the aqueous (water) - organic (kerosene) liquids is visualised and measured. A model for the prediction of liquid- liquid flow patterns in a circular T-shaped microchannel is designed using Probabilistic Neural Network (PNN). The designed PNN algorithm is explicitly validated by comparing the predicted patterns with the experimentally observed data.
Significance of exploiting non-living biomaterials for the biosorption of wastewater pollutants
Rangabhashiyam S., Suganya E., Selvaraju N., Varghese L.A.
Review, World Journal of Microbiology and Biotechnology, 2014, DOI Link
View abstract ⏷
Industrial effluents from various sectors have become a matter of major environmental concern. The treatment of wastewater in recent year plays a significant role in order to remove the pollutants and to safeguard the water resource. The conventional wastewater treatment is considered costlier and associated with problem of sludge generation. Biosorption methods are considered as the potential solution due to their economical efficiency, good adsorption capacity and eco-friendliness. In this review, an extensive list of biosorbents from algae, bacteria, fungi and agricultural byproducts have been compiled. The suitability of biosorbents towards the eradication of heavy metals, textile dyes and phenolic compounds were highlighted. It is evident from the literature survey of recently published research articles that the biosorbents have demonstrated outstanding removal potential towards the wastewater pollutants. Therefore, biosorbents from the source of dead microbial and agricultural byproduct can be viable alternatives to activated carbon for the wastewater treatment. © 2014 Springer Science+Business Media Dordrecht.
Equilibrium and kinetic modeling of chromium (VI) removal from aqueous solution by a novel biosorbent
Rangabhashiyam S., Anu N., Selvaraju N.
Article, Research Journal of Chemistry and Environment, 2014,
View abstract ⏷
The potential of a novel biosorbent Swietenia mahagoni fruit shell (SMFS) has been investigated for the confiscation of Cr(VI) from aqueous solution. The significant biosorption process parameters like pH, Cr(VI) concentrations and contact time were analyzed. Langmuir, Freundlich and Elovich isotherm models were used to model the adsorption equilibrium data. The Langmuir isotherm model better fitted the equilibrium data and the maximum adsorption capacity has been found as 2.309 mg g-1 .The kinetics studies demonstrated the pseudo first order rate lagergren model and pseudo second order. The biosorption process obeyed the pseudo second-order mode more than the pseudo first-order rate lagergren model. The biosorbent has been characterized through FTIR, SEM and EDAX respectively. The present studies revealed that SMFS could be subjected as an efficient biosorbent for the removal of Cr(VI) from aqueous solution.
Liquid-liquid slug flow in a microchannel reactor and its mass transfer properties – A review
Antony R., Giri Nandagopal M.S., Sreekumar N., Rangabhashiyam S., Selvaraju N.
Review, Bulletin of Chemical Reaction Engineering and Catalysis, 2014, DOI Link
View abstract ⏷
Mass transfer is a basic phenomenon behind many processes like reaction, absorption, extraction etc. Mass transfer plays a significant role in microfluidic systems where the chemical / biological process systems are shrinkened down to a micro scale. Micro reactor system, with its high compatibility and performance, gains a wide interest among the researchers in the recent years. Micro structured reactors holds advantages over the conventional types in chemical processes. The significance of micro reactor not limited to its scalability but to energy efficiency, on-site / on-demand production, reliability, safety, highly controlled outputs, etc. Liquid-liquid two phase reaction in a microreactor system is highly demandable when both reactants are liquids or when air medium cannot be suitable. This article overviews various liquid-liquid flow regimes in a microchannel. Discussions on the hydrodynamics of flow in micro scale are made. Considering the importance of mass transfer in liquid-liquid systems and the advantage of slug regime over other regimes, the article focuses especially on the mass transfer between two liquid phases in slug flow and the details of experimental studies carried out in this area. The advantages of slug flow over other flow regimes in micro structured reactor applications are showcased.
In situ separation of ethanol with aqueous two-phase system and assessment of KLa for yeast growth in batch cultivation
Hemavathy R.V., Sankaran K., Vadanasundari V., Rangabhashiyam S.
Article, Preparative Biochemistry and Biotechnology, 2014, DOI Link
View abstract ⏷
In the fermentation process, the separation of product and its purification is the most difficult and exigent task in the ground of biochemical engineering. Another major problem that is encountered in the fermentation is product inhibition, which leads to low conversion and low productivities. Extractive fermentation is a technique that helps in the in situ removal of product and better performance of the fermentation. An aqueous two-phase system was employed for in situ ethanol separation since the technique was biofriendly to the Saccharomyces cerevisiae and the ethanol produced. The two-phase system was obtained with polyethylene glycol 4000 (PEG 4000) and ammonium sulfate in water above critical concentrations, with the desire that the ethanol moves to the top phase while cells rest at the bottom. The overall mass transfer coefficient (KLa) was also estimated for the yeast growth at different rpm. The concentration and yield of ethanol were determined for conventional fermentation to be around 81.3% and for extractive fermentation around 87.5% at the end of the fermentation. Based on observation of both processes, extractive fermentation was found to be the best. © 2014 Copyright Taylor and Francis Group, LLC.
Advance approach on environmental assessment and monitoring
Giri Nandagopal M.S., Antony R., Rangabhashiyam S., Selvaraju N.
Review, Research Journal of Chemistry and Environment, 2014,
View abstract ⏷
Globalisation and industrialisation have led to tremendous expulsion of wide range of pollutants. These pollutants result in causing high level of health issues like chronic, acute and sometimes lethal. Monitoring and assessment of these pollutants is pertinent for the proper sequestration. The present equipments for environmental monitoring have the problems associated with sample handling, complex morphology and system portability. This has lead to an advanced level of research like microfluidics, integrates various assay reaction procedures and monitoring techniques in a palm. Microfluidics offers numerous advantages like high mass transfer coefficient, better reaction rate, low reactant utility, less wastage of chemicals, portability etc. With these significant properties, microfluidic devices are best suited for environmental analyses.
The significance of fungal laccase in textile dye degradation -a review
Rangabhashiyam S., Anu N., Selvaraju N.
Review, Research Journal of Chemistry and Environment, 2013,
View abstract ⏷
The effluent generated from the textile industry is the major threatening factor to the environment since it affects the biotic as well as the abiotic systems. The physical, chemical and biological methods are available for the textile dye effluent treatment .But the present study focuses on the importance of laccase, an effective enzyme for dye degradation through the various fungal source, the different classifications of the textile dye and the textile dye degradation.
Biosorption of heavy metals using low cost agricultural by products
Rangabhashiyam S., Anu N., Selvaraju N.
Review, Research Journal of Chemistry and Environment, 2013,
View abstract ⏷
Heavy metal pollution has risen from various sectors of industries like electroplating, fertilizer, leather. paint, pesticide, pharmaceuticals, pulp and paper, mining, oil refinery etc. The removal of heavy metals is of special concern due to their recalcitrance and persistence of existence in the environment. Utilizing agricultural by products as low-cost biosorbents is more attractive because of their biodegradablility in nature, highly economical, reduction of cost in agricultural waste management and having major contribution in the protection of the environment. In general the chemical modifications of agricultural by products bring out enhanced adsorption capacities than in the unmodified forms.
A holistic approach combining factor analysis, Positive Matrix Factorization and UNMIX applied to receptor modeling
Anu N., Rangabhashiyam S., Selvaraju N., Pushpavanam S.
Article, Journal of Scientific and Industrial Research, 2013,
View abstract ⏷
The contribution of various sources over the air pollution enables to establish effective control policies. The present work focuses on the holistic approach of combining factor analysis (FA), positive matrix factorization (PMF) and UNMIX in order to identify the sources and their contributions through analysis of ions and elements in particulate matter (PM10), organic carbon (OC) and elemental carbon (EC). Insight from the emission inventory, various models has been used to remove subjectivity in source identification. In the first method the proposed approach verified using a synthetic data and then the method has been again repeated with field (R.K Nagar, Chennai, India) study data. Factor analysis identified four factors with 99.7% of the variation in the measured data. PMF and UNMIX identified marine aerosol, fuel oil combustion, coal combustion and soil dust based on source profile and contribution results of synthetic dataset. The R.K Nagar data provided four sources such as marine aerosol, soil dust, coal combustion and secondary aerosols through the PMF and UNMIX. The obtained source contributions of these sources from PMF and UNMIX are 30.13% and 56.44%, 9.43% and 3.83%, 39.99% and 19.08%, 20.45% and 20.65% respectively.
Sequestration of dye from textile industry wastewater using agricultural waste products as adsorbents
Rangabhashiyam S., Anu N., Selvaraju N.
Review, Journal of Environmental Chemical Engineering, 2013, DOI Link
View abstract ⏷
Agricultural wastes products are quite commonly distributed as the result of agricultural practices. They are inexpensive and subject to biodegradable. Agricultural waste is a good source for the adsorption of the dyes generated during the textile processing. For the process of adsorption, agricultural waste products are used as natural or in the modified form through activation process. This review article focuses on the various sources of the agricultural waste products and its adsorption capacity of the different dyes. Signifying the potential of the use of agricultural wastes products for removing off the toxic dye substances from the effluent discharging into the water bodies. © 2013 Elsevier Ltd. All rights reserved.
Consequence of copper ions on thermal stability of glucoamylase from Aspergillus niger
Rangabhashiyam S., Vadana Sundari V., Hemavathy R.V., Sankaran K.
Article, International Journal of Pharma and Bio Sciences, 2011,
View abstract ⏷
The production of glucoamylase is carried out in the basal medium containing ammonium sulphate, magnesium sulphate, hydrated calcium chloride, and hydrated potassium dihydrogen phosphate by using medium optimization-Plackett Burman Design. Aspergillus niger is inoculated for the release of Glucoamylase into the surrounding medium. Then the supernatants collected by centrifugation is subjected for ammonium sulphate precipitation.Followed with this the sample is purified by using the ion exchange chromatography .The purified fractions of the sample is analyzed in SDSPAGE. The kinetic parameters measurements for the purified sample are carried out by using starch as substrate. The purified fractions are analyzed for the effect of copper ions and it is found to have maximum activity at 5mM concentration .Then the activation energy for the native glucoamylase is 94.46 KJ/mol and the copper modified glucoamylase is 119.98 KJ/mol. The copper modified glucoamylase is found to be stable at high temperature compared to that of native enzyme.
