Browsing by Author "Anwesha Borthakur"

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A critical review on the research trends and emerging technologies for arsenic decontamination from water
(Elsevier B.V., 2021) Pardeep Singh; Anwesha Borthakur; Rishikesh Singh; Rahul Bhadouria; Vipin Kumar Singh; Pooja Devi
To understand the current research output on arsenic (As) removal and research related to the As contamination, a bibliometric analysis based on Scopus database was carried out. The analysis includes the research covering the leading countries and year wise literature outputs. Bibliometric analysis revealed increasing trend in research published on As removal (more than 1200 articles) using physico-chemical methods during 1995 onwards and United States of America (USA) as leading contributor. Among different research institutions, Chinese Academy of Sciences has contributed maximally to research articles reaching up to 950 and maximum 635 research articles were published in the journal Environmental Science and Technology with respect to As removal using physico-chemical methods. With respect to As removal using biological methods, around 400 research articles were recorded during 1995 onwards and maximum article contribution (1052) was registered for China followed by USA (964). Based on Scopus data 2021, maximum 222 articles on As removal using biological methods were recorded for the journal ‘Chemosphere’. The present review emphasizes on currently available physico-chemical as well as emerging treatment processes for the removal of As, generally occurring as arsenite and arsenate, from drinking water. It has been suggested by various studies that a combination of low-cost physico-chemical treatment methodologies like ion exchange, reverse osmosis, precipitation, filtration and adsorption along with biological methods can be a safe alternative for As removal from drinking water. Overall, the study suggests that there is a strong need for further research on efficient processes involving lab to land approaches for As removal from groundwater in order to reduce the toxicity and contamination of As in drinking water. © 2021 Elsevier B.V.
Agriculture in the era of climate change: Consequences and effects
(Elsevier, 2019) Rahul Bhadouria; Rishikesh Singh; Vipin Kumar Singh; Anwesha Borthakur; Arif Ahamad; Gaurav Kumar; Pardeep Singh
The changing environmental conditions, especially global warming and climate variability, are major concerns and have an adverse impact over the future of agriculture. The changing climate has become a global issue which needs rapid policy development at national and international levels. The melting of massive Himalayan glaciers would considerably change the impact of temperature regimes which is necessary for blossoming of several crop plants. Thus, the current generation needs to find solutions to combat the negative impacts of environmental consequences on agricultural crops. Useful strategies include the conservation of the world’s huge biodiversity together with other natural resources. Modifications in currently used agricultural practices and the search for new plant species tolerant to different abiotic and biotic environmental stresses could help to mitigate the negative impact of climate change. © 2019 Elsevier Inc. All rights reserved.
Biological degradation of toluene by indigenous bacteria Acinetobacter junii CH005 isolated from petroleum contaminated sites in India
(Joint Center on Global Change and Earth System Science of the University of Maryland and Beijing Normal University, 2018) Pardeep Singh; Vipin Kumar Singh; Rishikesh Singh; Anwesha Borthakur; Ajay Kumar; Dhanesh Tiwary; P.K. Mishra
The bacterium Acinetobacter junii was isolated from petroleum-contaminated site in India and tested for its efficiency in degradation of toluene under aerobic condition. Within pH range 4–9, the optimum pH for toluene biodegradation was found to be 7.5. With increase in time, there was enhancement in degradation of toluene. Pure culture of Acinetobacter junii was able to degrade 69, 73 and 80% of 150, 100, and 50 ppm toluene, respectively, within 72 h at 37 °C. Simultaneous growth and degradation of toluene by the bacterium indicated the utilization of toluene as carbon source. After 72 h of treatment, toluene biodegradation was nearly stable. Scanning electron microscopic characterization of bacterial cells treated with toluene revealed the changes in surface morphology. Some of the cylindrical cells of bacterium got transformed into ovoid and spherical shape to escape the toluene toxicity. Degradation intermediates were identified by gas chromatography–mass spectroscopy. The major intermediate compounds identified after toluene degradation by bacteria were 1-isopropenyl-4-methyl-1,3-cyclohexadiene; 1,3-Cyclohexadiene; 2-methyl-5-(1-methylethyl); 4-methoxycarbonyl-4-butanolide; and vinyl (2E,4E)-2,4-hexadienoate, which are less-toxic in nature. The degradation of toluene into non-toxic intermediate compounds as well as the growth in the presence of toluene presents the suitability of Acinetobacter junii in biofiltration of toluene-containing petroleum waste. © 2018, Joint Center on Global Change and Earth System Science of the University of Maryland and Beijing Normal University and Springer-Verlag GmbH Germany, part of Springer Nature.
Bioremediation: A sustainable approach for management of environmental contaminants
(Elsevier, 2019) Pardeep Singh; Vipin Kumar Singh; Rishikesh Singh; Anwesha Borthakur; Sughosh Madhav; Arif Ahamad; Ajay Kumar; Dan Bahadur Pal; Dhanesh Tiwary; P.K. Mishra
The release of various inorganic and organic chemicals from various industries such as petrochemicals, textiles, pharmaceuticals, agro-based industries, and tanneries is highly toxic to the environment and human health. Several processes and technologies such as physical, chemical, and advanced oxidation processes are available for treatment of these pollutants. However, these processes and technologies have their own limitations and the end products are also of toxic nature. Therefore, there is a need for identifying and exploring sustainable and eco-friendly methods which require a lesser amount of chemicals, are economically feasible, and produce nontoxic end products. The bioremediation approaches to clean up environmental pollutants are considered as emerging and sustainable methods recently. Bioremediation process is based on an integrated approach employing microbial communities such as actinomycetes, bacteria, fungi, and earthworms. It is considered as a sustainable process for management of organic pollutants-rich solid wastes and wastewater. Many microorganisms metabolize toxic chemicals to produce CO2 or CH4, water, and biomass. These pollutants may be enzymatically altered to metabolites that are less noxious or innocuous. Moreover, the solid residue generated in this process has been found to have a potential influence on soil macro- and micronutrients, indicating its application as organic manure. However, bioremediation technique required more research for its establishment at a larger scale with an emphasis on the environmental consequences of the end products. In this chapter, we have performed a literature survey based on biological methods for the management of organic pollutants. Microbes responsible for degradation processes have also been presented in the later part of the chapter. In this chapter, a thorough understanding of the bioremediation processes and methods applied for abatement and remediation of organic pollutants has been described in detail. © 2020 Elsevier Inc. All rights reserved.
Current and emerging trends in bioremediation of petrochemical waste: A review
(Taylor and Francis Inc., 2017) Pardeep Singh; Rajat Jain; Neha Srivastava; Anwesha Borthakur; D.B. Pal; Rishikesh Singh; Sughosh Madhav; Pratap Srivastava; Dhanesh Tiwary; Pradeep Kumar Mishra
Various industries release harmful petrochemical contaminants into the environment. To treat these petrochemical contaminants at source, different physical, chemical, and biological methods have been proposed and applied worldwide. However, physical and chemical methods have their own advantages and limitations; in this review, we majorly focused on the biodegradation of petrochemical wastes. First, a background study on the literature available in this field is presented. Second is a review of the toxic effects of petrochemical waste and various physical and chemical processes, followed by elaborate biological processes available for petrochemical waste degradation. Further, different aspects of bioremediation, such as modes, factors, limitations, and future perspectives are critically reviewed and presented. It was found that most of the studies performed on bioremediation of petrochemical waste employed bacteria for the degradation purpose. Some studies also made use of algae, fungi, yeast, genetically modified organisms, biosurfactants, or a consortium of these microbes. Moreover, use of bioremediation is still limited at field scale due to certain limitations, which have been elaborated in this article. Overall, we strongly believe that with bioremediation capturing the attention of environmentalists worldwide, there is still a prevailing need to scale up from lab to land level applications and adaptations. © 2017 Taylor & Francis Group, LLC.
Effect of nanoscale TiO 2 -activated carbon composite on Solanum lycopersicum (L.) and Vigna radiata (L.) seeds germination
(Joint Center on Global Change and Earth System Science of the University of Maryland and Beijing Normal University, 2016) Pardeep Singh; Rishikesh Singh; Anwesha Borthakur; Pratap Srivastava; Neha Srivastava; Dhanesh Tiwary; Pradeep Kumar Mishra
The extensive use of nanoparticles under different industrial processes and their release into the environment are of major concerns in the present global scenario. In the present study, the effects of activated carbon-based TiO 2 (AC-TiO 2 ) nano-composite on the seed germination of Solanum lycopersicum (tomato) and Vigna radiata (mungbean) were investigated. The size of nanoparticles used in the study ranged from 30 to 50 nm, and their concentrations were from 0 to 500 mg L −1 . The composites were synthesized by sol–gel method and further characterized by scanning electron microscopy, Energy-dispersive X-rays spectroscopy (EDX), Raman spectroscopy, Fourier transform infrared spectroscopy and X-ray diffraction to investigate all the surface structural and chemical properties of AC-TiO 2 nano-composite. The results showed that increase in nano-composite concentration improves the germination rate and reduces germination time up to a certain concentration. Therefore, employing AC-TiO 2 nano-composites in suitable concentration may promote the seed germination and also reduce the germination time in Solanum lycopersicum and Vigna radiata. Further, it may help to understand the interface of TiO 2 nanoparticles with the environment and agriculture before its application to the field. © 2016, Joint Center on Global Change and Earth System Science of the University of Maryland and Beijing Normal University and Springer-Verlag Berlin Heidelberg.
Emerging trends in photodegradation of petrochemical wastes: a review
(Springer Verlag, 2016) Pardeep Singh; Ankita Ojha; Anwesha Borthakur; Rishikesh Singh; D. Lahiry; Dhanesh Tiwary; Pradeep Kumar Mishra
Various human activities like mining and extraction of mineral oils have been used for the modernization of society and well-beings. However, the by-products such as petrochemical wastes generated from such industries are carcinogenic and toxic, which had increased environmental pollution and risks to human health several folds. Various methods such as physical, chemical and biological methods have been used to degrade these pollutants from wastewater. Advance oxidation processes (AOPs) are evolving techniques for efficient sequestration of chemically stable and less biodegradable organic pollutants. In the present review, photocatalytic degradation of petrochemical wastes containing monoaromatic and poly-aromatic hydrocarbons has been studied using various heterogeneous photocatalysts (such as TiO2, ZnO and CdS. The present article seeks to offer a scientific and technical overview of the current trend in the use of the photocatalyst for remediation and degradation of petrochemical waste depending upon the recent advances in photodegradation of petrochemical research using bibliometric analysis. We further outlined the effect of various heterogeneous catalysts and their ecotoxicity, various degradation pathways of petrochemical wastes, the key regulatory parameters and the reactors used. A critical analysis of the available literature revealed that TiO2 is widely reported in the degradation processes along with other semiconductors/nanomaterials in visible and UV light irradiation. Further, various degradation studies have been carried out at laboratory scale in the presence of UV light. However, further elaborative research is needed for successful application of the laboratory scale techniques to pilot-scale operation and to develop environmental friendly catalysts which support the sustainable treatment technology with the “zero concept” of industrial wastewater. Nevertheless, there is a need to develop more effective methods which consume less energy and are more efficient in pilot scale for the demineralization of pollutant. © 2016, Springer-Verlag Berlin Heidelberg.
Exploring temple floral refuse for biochar production as a closed loop perspective for environmental management
(Elsevier Ltd, 2018) Pardeep Singh; Rishikesh Singh; Anwesha Borthakur; Sughosh Madhav; Vipin Kumar Singh; Dhanesh Tiwary; Vimal Chandra Srivastava; P.K. Mishra
Religious faith and ritual activities lead to significant floral offerings production and its disposal as waste to the nearby open lands and water bodies. These activities result into various social and environmental nuisances because of their high organic content. Alternatively, it can be used as valuable resources for various biochemical and thermo-chemical processes. Floral refuse has been utilized in natural dye extraction, however, the residual solid refuse is of significant environmental concern due to its nutrient rich nature. This study explores the potential utilization of solid residue of temple floral refuse after natural dye extraction by thermo-chemical decomposition of it. The slow pyrolysis of solid residue was performed at 350 °C and 500 °C, and the biochar yield of 42 and 36% was obtained, respectively. TGA-DTG analysis was performed to observe the thermo-chemical behaviour of floral refuse. The biochar products were further characterized by FTIR, SEM, EDX, BET, XRD, and RAMAN spectroscopy to observe the impact of pyrolysis temperature (PT) on the resulting material, i.e. biochar and its possible application measures. EDX results revealed the presence of various macro-nutrients such as C, N, P, K Ca and Mg in different proportions which showed its soil amelioration potential. Moreover, based on the SEM and BET results, biochar prepared at 500 °C was further explored for adsorption of methylene blue dye at various dose and pH conditions. Based on Langmuir (R2 = 0.98) and Freundlich (R2 = 0.97) isotherms, it is found as a potential adsorbent material for removal of methylene blue dye. The results revealed that biochar conversion of colour extracted floral refuse can be a vital option for quick and efficient management of it in a closed loop approach. © 2018 Elsevier Ltd
Photocatalytic degradation of Acid Red dye stuff in the presence of activated carbon-TiO2 composite and its kinetic enumeration
(Elsevier Ltd, 2016) Pardeep Singh; M.C. Vishnu; Karan Kumar Sharma; Anwesha Borthakur; Pratap Srivastava; D.B. Pal; Dhanesh Tiwary; Pradeep Kumar Mishra
The present paper deals with photocatalytic degradation of effluents from dye industries which have known toxic impacts on flora and fauna. Nano composite of titanium dioxide having activated carbon (TiO2/AC) base was synthesized using sol-gel method. The synthesized catalyst was then characterized by Fourier Transform-Infrared (FT-IR) spectroscopy, Scanning Electron Microscopy (SEM), X-ray Diffractometry (XRD) and Brunauer Emmet Teller (BET) surface area analyzer. A synthetic solution of AR-131 dye was subjected to photocatalytic degradation using TiO2/AC nano composite as catalyst. The degradation mechanisms of dye (AR-131) via photo-catalysis were found to follow a first order kinetics mechanism (vis. Langmuir- Hinshelwood Model). Toxicity of spent catalysts was further investigated in seed germination of Vigna radiata. Enhanced seed germination along with elongation of root and shoot was noticed up to the concentration of 500 ppm confirming its non toxicity. © 2016 Elsevier Ltd.