Browsing by Author "Chauhan, Amit Kumar"
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Item Advanced membrane technology for the removal of pesticides from water and wastewater(Elsevier, 2022-05-21T00:00:00) Yadav, Sangita; Chauhan, Amit Kumar; Kumar, Sandeep; Kataria, NavishAgricultural runoff is one of the main factors that introduces pesticide residue into water. Common pesticides such as DEET(N,N-diethyl-meta-toluamide), DDT(dichloro diphenyl trichloroethane), metolachlor, malathion, etc., have continuously contaminated water systems. These pesticides are toxic and can cause detrimental effects on living organisms, even at trace amounts. Most pesticides are grouped into chemical families and persist the environment for long periods. Therefore, specific water treatment is required to clean the waterbodies contaminated with pesticides. Several conventional treatment methods have been introduced in the past to decontaminate the waterbodies. However, there are many advantages and disadvantages associated with these processes. Nowadays, membrane technology is one of the best and preferred method available to treat contaminated water because of its high efficiency, cost effectiveness, easy applicability, stability, and low footprint. Membrane filtration includes reverse osmosis, nanofiltration, ultrafiltration, nanofiber filtration, and biomembrane filtration processes for pollution separation. Membrane materials and filtration processes can be modified depending on the chemical structure and properties of the pesticides. Recent advances in nanotechnology offer energy-efficient, low cost, and eco-friendly approaches in water treatment technologies. Membrane materials can be modified to obtain better results and increase its effectiveness for treatment process. Recently, researchers have started working to introduce new nanomaterials including carbon nanotubes, nanopolymers, metal-organic nanomembrane, graphene, quantum and nanoshells development of membrane filters for water purification. Recently, membrane materials progress has allowed filtration to become more effective over other conventional treatment methods and popularized globally. � 2022 Elsevier Inc. All rights reserved.Item Biogenic fabrication of ZnO@EC and MgO@EC using Eucalyptus leaf extract for the removal of hexavalent chromium Cr(VI) ions from water(Springer Science and Business Media Deutschland GmbH, 2023-01-04T00:00:00) Chauhan, Amit Kumar; Kataria, Navish; Gupta, Renuka; Garg, Vinod KumarZinc and magnesium oxide nanoparticles were fabricated using green synthesis method for the sequestration of hexavalent chromium Cr(VI) from the aqueous medium. The biogenically prepared ZnO@EC and MgO@EC nanoparticles were successfully loaded on the Eucalyptus. The prepared nanomaterials were characterized using various techniques such as FESEM, TGA, XRD, EDX, FTIR, BET, and elemental mapping. FE-SEM analysis has revealed the surface morphology of ZnO nanoparticles, which were rod-like and spherical in shape, whereas MgO nanoparticles were of irregular shape. Batch mode was selected to remove the hexavalent chromium from aqueous solution using the prepared nanomaterials. The Cr(VI) adsorption was carried out under optimized conditions, viz., pH (3.0), adsorbent dose (0.05�g), contact time (150�min), temperature (25 � 2��C), and initial concentration (50�mg/L). The experimental results were compared using the different isotherm models; The observations have indicated that experimental data fit better with Freundlich (R2 = 0.99) and Langmuir (R2 = 0.99)�isotherms, respectively. The maximum adsorption capacity of ZnO@EC and MgO@EC for Cr(VI) was found to be 49.3 and 17.4�mg/g, respectively. The regeneration study of the adsorbents was conducted using different desorbing agents viz., ethanol, NaOH, and NaCl. The desorbing agent NaOH performed better and showed removal percentage of 34.24% and 20.18% for ZnO@EC and MgO@EC, respectively, after the three reusability cycles. The kinetics of reaction was assessed using the pseudo-first-order and pseudo-second-order kinetic models. The experimental data of both the nanomaterials ZnO@EC and MgO@EC obeyed pseudo-second-order model with correlation coefficient values 0.999 and 0.983, respectively. The thermodynamic study confirmed that adsorption was feasible, spontaneous, and endothermic. The adsorbents were tested for spiked real water which confirms their applicability and potential in real water systems also. The results indicated fair removal of chromium suggesting applicability of both adsorbents. � 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.Item COVID-19 pandemic: An outlook on its impact on air quality and its association with environmental variables in major cities of Punjab and Chandigarh, India(Bellwether Publishing, Ltd., 2020-10-31T00:00:00) Sahoo, Prafulla Kumar; Chauhan, Amit Kumar; Mangla, Sherry; Pathak, Ashok Kumar; Garg, V.K.The present study aims to evaluate the impact of COVID-19 lockdown on air quality and to explore the association of daily COVID-19 confirmed cases with meteorological parameters and criteria pollutants in the major cities of Punjab and Chandigarh, India during the different phase of pre-lockdown (March 1 to March 24), lockdown (1.0, 2.0, 3.0, 4.0; March 25 to May 31), and unlock (1.0, 2.0; > June 1) in 2020. Our results show that the COVID-19 lockdown has drastically improved the quality of air in major cities of Punjab and Chandigarh. Compared to pre-lockdown, maximum reduction of PM2.5 and PM10 levels (up to ?52 and ?53.5%, respectively) was witnessed during lockdown 1.0, but their levels were rising again during the last phase of lockdown and unlock phases. This is due to more relaxation and traffic returned on the road. Among other pollutants, NO2 also reduced during lockdown 1.0, but remained variable between cities and different phases of lockdown and unlock periods. However, surface-level ozone resulted in an overall increase trend during the lockdown and unlock phases. Regarding the relationship between COVID-19 and meteorological parameters, Spearman correlation test shows that ambient temperature is positively correlated with COVID-19 daily confirmed cases (r < 0.77, p < 0.01). This result indicates that the study region�s hot tropical weather is less effective in controlling the spread of COVID-19. Relative humidity and wind speed are also weakly correlated with COVID-19. Furthermore, among criteria pollutants, PM2.5 and PM10 are positively correlated (r < 0.55, p < 0.01) with COVID-19 pandemic, especially in Jalandhar and Ludhiana, suggesting that these pollutants could lead to the spreading of the virus. However, further in-depth studies are required to validate this finding. The results of this study can contribute to the understanding of the role of environmental factors in the transmission of COVID-19 in tropical and sub-tropical countries like India, Brazil, etc. This study also indicates that the temporarylockdown like COVID-19 can be emerged as an effective way to control environmental imbalancein the study area, as well as in other areas. � 2020 Informa UK Limited, trading as Taylor & Francis Group.Item Hybrid nanomaterials for the removal of organic pollutants from wastewater(Elsevier, 2023-04-21T00:00:00) Sharma, Anchal; Chauhan, Amit Kumar; Kataria, Navish; Garg, Vinod KumarNanomaterials have recently gained the attention of the scientific community due to their multifarious applications and excellent properties. The unique properties of nanomaterials include small size, high surface area-to-volume ratio, porous structure, magnetic behavior, thermal stability, photocatalysis, etc. Industrial activities are continuously enhancing the pollutant load in different environmental matrices, including aqueous systems. These pollutants may enter the food chain and exert adverse health effects and environmental problems. At this stage, interventions are urgently required to handle water pollutants. Several hybrid nanomaterials including metal oxide/carbon nanocomposites, metal doped composites, surface-functionalized carbon nanotubes and graphene oxide, metal oxide-coated metal oxide frameworks, bimetallic coated biopolymers, metal-coated biomaterials, green fabricated metal/carbon nanocomposites, etc., are being designed and fabricated for the treatment of wastewater. Hybrid nanomaterials have been utilized in various treatment methods such as adsorption, photocatalysis and catalytic reduction, membrane filtration, and an advanced oxidation process for the removal of inorganic and organic compounds. This chapter focuses on the application of hybrid nanomaterials for the removal of organic pollutants from wastewater systems. It also describes the current research progress of nanotechnology in environmental applications with a special emphasis on pollution prevention and the removal of environmental contaminants from contaminated drinking water and industrial wastewater. � 2023 Elsevier Inc. All rights reserved.Item Recent Advancement in Nanotechnology for the Treatment of Pharmaceutical Wastewater: Sources, Toxicity, and Remediation Technology(Springer Science and Business Media Deutschland GmbH, 2023-03-11T00:00:00) Kumar, Sandeep; Yadav, Sangita; Kataria, Navish; Chauhan, Amit Kumar; Joshi, Seema; Gupta, Renuka; Kumar, Parmod; Chong, Jun Wei Roy; Khoo, Kuan Shiong; Show, Pau LokeThe textile, paper and pulp, distillery, and pharmaceutical industries are only a few of the many sectors that contribute significantly to the contamination of water bodies and their unsuitability for human use. Pharmaceuticals, which are credited with saving millions of lives in recent decades, have emerged as a new category of environmental hazard. Their prolonged presence in the environment has a number of negative effects, including gene toxicity, hormone interference, antibiotic resistance, the imposition of sex organs, and many others. To ensure that everyone in the world can access to uncontaminated and safe drinking water, it is important to treat pharmaceutical laden wastewater before discharge in fresh water body. Nanotechnology is getting significant attention due to enormous properties such as the high surface area to volume ratio, new optical properties, and desired shape. Nanomaterials might be a strong option for purifying water of a variety of environmental pollutants. This review also touches on several environmental aspects of pharmaceuticals, including (i) the current status of pharmaceuticals production and their use pattern, (ii) sources, occurrence, and transport behaviour of pharmaceuticals, (iii) analysis techniques and potential toxicity of pharmaceuticals and (iv) various conventional and advanced nanotechnology for water remediation. The present review is predominately designed to highlight the progress and major update in advantaged nanotechnology for remediation of pharmaceutical contaminated wastewater. The literature study (2015�2022) critically illustrated the recent pharmaceutical contaminations concerns and remediation efforts emphasizing nanotechnology like nanoadsorption, AOPs, nano-catalyst, electrochemical degradation and nanomembrane/nanofiltration technology. � 2023, The Author(s), under exclusive licence to Springer Nature Switzerland AG.Item Sequestration of heavy metals from contaminated water using magnetic carbon nanocomposites(Elsevier B.V., 2022-03-30T00:00:00) Kataria, Navish; Chauhan, Amit Kumar; Garg, V.K.; Kumar, ParmodHeavy metals are toxic to flora, fauna and human beings. This study focused on removing toxic metals from an aqueous medium using magnetic carbon (Fe3O4@Carbon) nanocomposites. The biogenic green synthesis approach was used to fabricate the magnetic nanocomposite using low-cost poplar sawdust powder. The characterization of the nanocomposites was done using FESEM, TEM BET and FTIR. The sequestration of Pb (II), Cu (II) and Cr (VI) from water by Fe3O4@Carbon nanocomposites were studied under batch mode. The adsorption capacities for Pb (II), Cu (II) and Cr (VI) were 151.5, 48.08, and leaves49.29 mg/g respectively. The removal of metals by magnetic composites was studied in a mono, binary and tertiary network of metal ions. Adsorption isotherms studies indicated the chemosorption of Cu (II) and Cr (VI) onto the surface of nanocomposites. The thermodynamic analysis revealed that removal of studied metals ions is spontaneous and feasible. In this study, the effectiveness of magnetic nanocomposites is also explored for the removal of other heavy metals from tap water and simulated water sample. The heavy metal removal efficiency of the nanocomposites was not affected up to thrice reuse of adsorbent. � 2022