Browsing by Author "Babu, J. Nagendra"

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1,3-Bis(cyanomethoxy)calix[4]arene capped CdSe quantum dots for the fluorogenic sensing of fluorene
(Royal Society of Chemistry, 2017) Kumar, Rabindra; Arora, Meenu; Jain, A.K.; Babu, J. Nagendra
Capping of 1,3-bis(cyanomethoxy)-tert-butylcalix[4]arene (CAD) onto CdSe quantum dots (QDs) was characterized by a fluorescence enhancement of the QDs (?em = 580 nm) upon surface interaction with the phenolic moiety of CAD. CAD@QD showed selective and sensitive 1.67 fold fluorescence enhancement in the presence of fluorene among fifteen PAHs. The fluorescence enhancement was characterized by monolayer adsorption of fluorene on to the surface of CAD@QD. The limit of detection for fluorene was observed to be 0.8 nM. This method was used and compared with detection of fluorene in spiked respirable dust (PM10) samples collected during an open biomass (stubble) burning event. ? The Royal Society of Chemistry.
Adsorption of Zn(II) on Pristine and SPLP/TCLP Leached Rice Straw Biochar: an Interplay of Precipitation and Ion Exchange
(Institute for Ionics, 2022-11-15T00:00:00) Bhardwaj, Akanksha; Nag, Shilpa; Hussain, Khadim; Arora, Meenu; Pandey, Puneeta; Babu, J. Nagendra
The inorganic mineral content in biochar influences the adsorption of Zn(II) metal ions. Metal ion adsorption on mineral rich rice straw biochar is influenced upon washing. Rice straw slow pyrolysis biochar BC1-3, respectively, prepared at 400, 500, and 600��C, were leached under Toxicity Characteristic Leaching Procedure (TCLP) and Synthetic Precipitation Leaching Procedure (SPLP) conditions to furnish BT1-3 and BS1-3, respectively. The Zn(II) adsorption studies were carried out for pH and dose optimization, initial concentration, isotherm fit, and kinetic studies. The Zn(II) adsorption by B(C/S/T)1�3 showed Langmuir and Freundlich isotherm, with pseudo-second-order kinetics at optimum pH 5 and dose 1�g/L. The adsorption of Zn(II) followed the trend BC3(qm 47�mg/g) > BC2 > BC1 > BS2 > BS1 > BS3 > BT2 > BT1 > BT3 (qm 3.5�mg/g), i.e., metal ion adsorption decreased with extent of leaching. The Zn(II) adsorption on biochar involved precipitation as dominant factor for metal ion adsorption on the biochars followed by ion exchange and proton exchange. The precipitation of Zn(II) ions in case of BC1-3 is attributed to the pH of biochar, which increases with proportion of minerals to organic content in biochar. In case of biochar BS1-3 and BT1-3, ion exchange and proton exchange mechanisms driven by demineralization are responsible for Zn(II) adsorption. The adsorption mechanism for Zn(II) on biochar is supported by XPS, solid state NMR studies. Graphical Abstract: [Figure not available: see fulltext.] � 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.
Direct Michael addition/decarboxylation reaction catalyzed by a composite of copper ferrite nanoparticles immobilized on microcrystalline cellulose: an eco-friendly approach for constructing 3,4-dihydrocoumarin frameworks
(Royal Society of Chemistry, 2022-10-27T00:00:00) Kumar, Bhupender; Borah, Biplob; Babu, J. Nagendra; Chowhan, L. Raju
A composite of copper ferrite oxide nanoparticles immobilized on microcrystalline cellulose (CuFe2O4@MCC) was synthesized. The synthesized composite was characterized by FESEM with EDS-Mapping, TEM, P-XRD, TEM, and BET analysis and investigated for its catalytic activity toward Tandem Michael addition and decarboxylation of coumarin-3-carboxylic acid with cyclic 1,3-diketones to obtain novel 3,4-dihydrocoumarin derivatives. This protocol was established with wide substrate scope and significant yield. The significant characteristics of this methodology are mild reaction conditions, easy setup procedure, non-toxic, and cost-effectiveness. A gram-scale synthesis with low catalyst loading was also demonstrated. � 2022 The Royal Society of Chemistry.
Effect of Pyrolysis Temperature on Mechanistic Transformation for Adsorption of Methylene Blue on Leached Rice-Straw Biochar
(John Wiley and Sons Inc, 2022-02-09T00:00:00) Bhardwaj, Akanksha; Nag, Shilpa; Dahiya, Amarjeet; Pandey, Puneeta; Arora, Meenu; Babu, J. Nagendra
Toxicity characteristic leaching procedure (TCLP) leached biochar is studied for adsorption of methylene blue (MB). Rice straw biochar obtained from slow pyrolysis at 400, 500, and 600��C, respectively, is TCLP leached to furnish leached biochar, BL4, BL5, and BL6. The leached biochar BL4�6 have been characterized for pH, CHN analysis, ash, zeta potential, surface area morphology and functional groups. Batch adsorption studies are optimized for pH (3�9), adsorbent dose (0.5�4�g�L?1), and initial MB concentration (20�135�mg�L?1). Nonlinear fitting to Langmuir, Freundlich, and Redlich-Peterson adsorption isotherm with due statistical treatment and error function analysis is carried out. Leached biochar, BL4, BL5, and BL6, is characterized by the dominance of carboxylic acid, lactone, and phenols moieties, respectively. The MB adsorption on leached biochar exhibits maximum adsorption of 26.87, 51.34, and 18.83�mg�g?1 for BL4, BL5, and BL6, respectively. The underlying mechanism for adsorption of MB using BL5, is characterized by non-ionic lactone ring opening in presence of MB under alkaline conditions that is supported by X-ray photoelectron spectroscopy(XPS) and Fourier transformed infrared spectroscopy (FTIR) studies. Desorption of MB and regeneration from BL5 is studied with methanol and 0.1 m HCl as stripping solvent for four cycles. Recovery of MB is better with methanol in comparison to 0.1 m HCl. � 2022 Wiley-VCH GmbH.
Effect of temperature and fly ash content on the catalytically pyrolyzed rice straw biochar�fly ash composites for methylene blue adsorption
(John Wiley and Sons Ltd, 2022-09-26T00:00:00) Bhardwaj, Akanksha; Nag, Shilpa; Hussain, Khadim; Pandey, Puneeta; Babu, J. Nagendra
Rice straw and fly ash are the wastes produced in abundance which need immediate attention for their management. In the present study, the in situ pyrolysis of rice straw in presence of fly ash was carried out and the resultant composites were studied for adsorption of methylene blue (MB). Slow pyrolysis of rice straw in presence of fly ash is evaluated using thermogravimetric analysis (TGA) and Coats�Redfern equation for pseudo-first-order reaction kinetics, respectively. The activation energy (Ea) for the pyrolysis of rice straw was 41.75 kJ/mol which was lowered to 37.39 kJ/mol in presence of fly ash. Biochar fly ash composites BFA41�3, BFA51�3, and BFA61�3 were prepared at three 400�C, 500�C, and 600�C pyrolysis temperature, respectively, the subscript indicating three different ratios of rice straw and fly ash (1:3, 1:1, and 3:1 w/w ratio). The composites BF4�61�3 were neutral to alkaline in pH, due to the presence of basic oxide and carbonates minerals. BFA4�61�3 was studied for batch adsorption of MB and optimized for pH, dose, and initial concentration of adsorbate. The maximum MB adsorption capacity of 25.91 mg/g was reported for the composite BFA41. MB adsorption efficiency (qe) followed the trend BFA41�3 > BFA51�3 > BFA61�3, which indicates a strong influence of biochar surface functional groups on dye adsorption, as reiterated by the multiple linear regression (MLR) analysis. Stripping of MB was achieved using methanol as a stripping agent for MB-adsorbed BFA4�61�3 with desorption efficiency of 7% to 11% in the first cycle and 23% to 100% in the second cycle. Thus, the biochar fly ash composite with optimum ion exchangeable functional organic moieties would be suitable for dye remediation and waste generated in the process could find application in soil amelioration. � 2022 Curtin University and John Wiley & Sons Ltd.
Fabrication of Monarda citriodora essential oil nanoemulsions: characterization and antifungal activity against Penicillium digitatum of kinnow
(Springer, 2023-02-13T00:00:00) Kaur, Kiranjot; Tandon, Ritu; Kalia, Anu; Babu, J. Nagendra
Postharvest fungal pathogenic invasions are the major root cause of reduced shelf life of kinnow fruit, thereby contributing to the postharvest losses. Development of eco-friendly alternates are the need of the hour owing to health safety concerns for replacing the ongoing synthetic fungicide use. Essential oils with promising antimicrobial activities offer a promising solution but their hydrophobicity poses a big hindrance for exploiting the same. Present work was planned to explore their antimicrobial potential by developing their hydrophilic formulation with the use of nanotechnology. An in vitro study was conducted to assess the efficacy Monarda citriodora essential oil (MCEO) and its emulsions against major postharvest fungal pathogen of Kinnow; Penicillium digitatum. Both micro and nano formulations were prepared for different ratios of MCEO (0.5 to 3%) with different surfactant combinations and oil-surfactant-ratios (OSR) of 1:1 to 1:3. The influence of several process factors such as surfactant and oil phase concentrations, as well as sonication time intervals on emulsion stability was investigated by assessing attributes such as droplet diameter, Polydispersity index (PDI), zeta (?) potential and rheology. An emulsion formulated with 1% oil and 1:1 OSR treated with ultrasonic waves for 15�min was optimized with droplet diameter of 52.2�nm, 0.245 PDI and ?�21�mV of ? potential with consistent stability till 1�month. Further, in vitro antifungal activity of the optimized MCEO nanoemulsion exhibited the best efficacy with 100% inhibition at 200�mg L?1. Graphical Abstract: [Figure not available: see fulltext.] � 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
In situ reductive regeneration of zerovalent iron nanoparticles immobilized on cellulose for atom efficient Cr( VI ) adsorption
(Royal Society of Chemistry, 2015) Sharma,Archana Kumari; Kumar,Rabindra; Mittal, Sunil; Hussain,Shamima; Arora, Meenu; Sharma, R.C.; Babu, J. Nagendra
Zerovalent iron nanoparticles (nZVI) (11.8 ± 0.2% w/w) immobilized on microcrystalline cellulose (C-nZVI) were synthesized and studied for Cr(VI) sorption. The material showed good atom economy for Cr(VI) adsorption (562.8 mg g−1 of nZVI). Oxidation of cellulose to cellulose dialdehyde leads to in situ regeneration of nZVI which is responsible for the atom efficient Cr(VI) sorption by C-nZVI.
In situ reductive regeneration of zerovalent iron nanoparticles immobilized on cellulose for atom efficient Cr(vi) adsorption
(Royal Society of Chemistry, 2015) Sharma, Archana Kumari; Kumar, Rabindra; Mittal, Sunil; Hussain, Shamima; Arora, Meenu; Sharma, R.C.; Babu, J. Nagendra
Zerovalent iron nanoparticles (nZVI) (11.8 - 0.2% w/w) immobilized on microcrystalline cellulose (C-nZVI) were synthesized and studied for Cr(vi) sorption. The material showed good atom economy for Cr(vi) adsorption (562.8 mg g-1 of nZVI). Oxidation of cellulose to cellulose dialdehyde leads to in situ regeneration of nZVI which is responsible for the atom efficient Cr(vi) sorption by C-nZVI.
Multifaceted application of crop residue biochar as a tool for sustainable agriculture: An ecological perspective
(Elsevier, 2015) Singh,Rishikesh; Babu, J. Nagendra; Kumar,Rabindra; Srivastava,Pratap; Singh, Pardeep; Raghubanshi,Akhilesh Singh
Lignocellulosic crop residue biomass, in surplus, is of vital importance due to its multifaceted utilization potential on- and off-site to agricultural systems; therefore, its management is essential for sustainable agriculture. The malpractice of open crop residue burning leading to the brown cloud phenomenon and contributing significantly to atmospheric heterogeneity through enhanced gaseous and particulate emissions is of greater off-late concern. Available traditional crop residue management (CRM) technologies have not achieved wider adaptation; therefore, recently thermochemical conversion has been foreseen as an interesting tool for potential CRM under changing climate scenario. Biochar, a by-product of thermochemical processes, has been evaluated as a potential soil ameliorant and C sequestration agent. As soil ameliorant, it improves soil basic properties directly along with subdued release of greenhouse gases from agroecosystems, provides adsorption surface to agrochemicals and improves essential nutrient dynamics. Since the potential benefits of biochar in soil are governed by initial pyrolysis conditions and soil types; therefore, its wider utilization potential as suitable tool in sustainable agriculture and climate change mitigation needs to be critically analyzed before its specific recommendation to an agroecosystem. The present review provides a critical insight on current research on various aspects, particularly ecological, of crop residue biochar starting from the feedstock sources, pyrolysis conditions and changes after application. Additionally, a brief account is given on the agronomic relevance and major constraints of biochar amendment as an ecological engineering tool for sustainable agriculture. After reviewing various aspects of crop residue as feedstock, we recommend its use as a blend, rather than sole use, along with several other lignocellulosic materials under pyrolysis process as well as ameliorating agent. ? 2015 Elsevier B.V.
Polynuclear Aromatic Hydrocarbon (PAH) Inclusion in Lower Rim Substituted Calix[4]arene
(Central University of Punjab, 2018) Ram, Mange; Babu, J. Nagendra
Calix[4]arene was lower rim functionalized to furnish receptor 2-3 and 4-6, containing propyl and cynomethoxy moieties respectively. The receptors were characterized by FTIR, EI-MS, 1H and 13C NMR. UV-visible studies were performed with receptor 2-5 cone and 6th 1-3,aternate. (2x10-4) upon addition of Naphthalene, Anthracene and Pyrene. Upon addition of Naphthalene, Anthracene and Pyrene the UV-visible absorption showed hyperchromic shift. The one-to-one Host-Guest complexation studied by Benesi-Hildebrand equation showed stability constant in the range 2-10x104 M-1 .
Reduced and oxidized rice straw biochar for hexavalent chromium adsorption: Revisiting the mechanism of adsorption
(Elsevier Ltd, 2023-11-01T00:00:00) Dahiya, Amarjeet; Bhardwaj, Akanksha; Rani, Archana; Arora, Meenu; Babu, J. Nagendra
Surface oxygen functional groups of biochar were tuned by oxidation and reduction of biochar for establishing Cr(VI) adsorption mechanism. Oxygen functional groups (OFGs) on the surface of leached rice straw biochar (LBC4-6) obtained from pyrolysis at 400, 500 and 600 �C, were oxidized to furnish OBC4-6 using modified Hummer's method. Reduced biochar RBC4-6 were obtained by esterification and NaBH4/I2 reduction of oxidized biochar (OBC4-6). The modified biochar were characterized by increase in O/C and H/C ratio, respectively, in case of OBC4-6 and RBC4-6. The Cr(VI) adsorption by modified biochar LBC4-6, OBC4-6, and RBC4-6 showed optimum conditions of pH 3 and dose 0.1 g/L with a good non-linear fit for Langmuir & Freundlich isotherm. The maximum adsorption (Qm) followed the trend: OBC4 (17.47 mg/g) > RBC4 (15.23) > OBC5 (13.23) > LBC4 (10.23) > RBC5 (9.83) > OBC6 (9.60) > RBC6 (7.24) > LBC5 (6.32) > LBC6 (5.98). The adsorption kinetics for adsorption of Cr(VI) on to modified biochar fits pseudo second order (PSO), Elovich and intraparticle diffusion kinetics, showing a chemisorptions in case of biochar L/O/RBC4-6. The lower temperature modified biochar O/RBC4 show better Cr(VI) adsorption. X-ray Photoelectron Spectroscopy (XPS) studies establish optimum OFGs for reduction of Cr(VI) and chelation of the reduced Cr(III). Adsorption and stripping cycles show the oxidized and reduced biochar as better adsorbents with excellent stripping of Cr up to >98 % upon desorption with 1 M NaOH. � 2023
Reductive-co-precipitated cellulose immobilized zerovalent iron nanoparticles in ionic liquid/water for Cr(VI) adsorption
(Springer Netherlands, 2018) Sharma, Archana Kumari; Devan, Rupesh S.; Arora, Meenu; Kumar, . Rabindra; Ma, Yuan-Ron; Babu, J. Nagendra
Microcrystalline cellulose immobilized zerovalent iron nanoparticles (CI-1-3) with different loading of 6, 12 and 24% w/w Fe0 were synthesized by NaBH4 reduction under simultaneous co-precipitation of cellulose from ionic liquid ([BMIM]Cl)-water binary mixture. SEM, TEM, FTIR, VSM, XRD and XPS analysis were carried out to characterize the material. The electron microscopy studies revealed the immobilization of iron nanoparticle in the bulk and surface of microcrystalline cellulose with a size range of 20–100 nm. CI-1-3 showed strong interaction between cellulose hydroxyl moiety and nZVI, immobilized on the polymer and saturation magnetization of 3 emu/g for CI-2. The materials were studied for Cr(VI) adsorption which revealed the qmax value of 28.57, 58.82 and 38.48 mg Cr(VI)/g of CI-1-3, respectively.
Removal of hexavalent chromium from aqueous solution using biomass derived fly ash from Waste-to- Energy power plant
(Taylor & Francis, 2013) Vaid, Upma; Mittal, Sunil; Babu, J. Nagendra
Fly ash from the agricultural waste-based Energy Power Plant has been studied for the adsorption of hexavalent chromium [Cr(VI)]. In order to maximize the Cr(VI) removal from simulated aqueous solutions, effects of various parameters i.e. adsorbent dose (10–40 g/L), contact time (5–90 min), variation in pH (1–5), and initial metal ion concentration (10–80 mg/L) on Cr(VI) adsorption were investigated by batch adsorption experiments. It was observed that adsorption of Cr(VI) on the selected adsorbent was dependent on pH. Before optimization of experimental conditions, the percent removal of Cr(VI) from the aqueous solution (10 mg Cr/L) was approximately 4%, which increased to approximately 99% after optimization of experimental conditions. Maximum adsorption was observed upon adding 10 g/L of adsorbent to a 60 mg Cr/L aqueous solution at pH 1.0 and contact time of 90 min at 200 rpm. Equilibrium adsorption data were well fitted in Langmuir isotherm model which substantiate monolayer adsorption of Cr(VI) on fly ash. Kinetics of Cr(VI) adsorption on fly ash follows pseudo-second-order reaction.
Removal of hexavalent chromium from aqueous solution: a comparative study of cone biomass of “Picea smithiana” and activated charcoal
(Taylor & Francis, 2016) Mittal, Sunil; Vaid, Upma; Najar, Gh Nabi; Babu, J. Nagendra
The present work investigates comparative adsorption efficiency of powdered cone biomass of Picea smithiana (PCBP) and activated charcoal (AC) for removal of hexavalent chromium (Cr) (Cr(VI)) from aqueous solution. The study indicates that PCBP has 76% removal efficiency for Cr as compared to AC. Particle size and SEM-EDX analyses were done to determine average particle size, surface morphology and elemental composition of PCBP. BET and FTIR analysis were carried out to elucidate the adsorption mechanism of Cr(VI) on PCBP. Ashing has been proposed as a method for managing waste of loaded PCBP generated in adsorption. Ashing studies showed the ash content of PCBP to contribute only 13% of the ash generated from loaded biomass. Further, a comparative study has been made indicating the adsorption efficiency of PCBP with previously reported bio-waste materials. The results of this study show that PCBP has high adsorption efficiency as compared to other bio-waste materials.
Role of soil physicochemical characteristics on the present state of arsenic and its adsorption in alluvial soils of two agri-intensive region of Bathinda, Punjab, India
(Springer Verlag, 2016) Kumar, Ravishankar; Kumar, Rabindra; Mittal, Sunil; Arora, Meenu; Babu, J. Nagendra
Purpose: Arsenic (As) contamination of groundwater has received significant attention recently in district Bathinda, due to consequent health risk in this region. Soil is the one of the primary medium for arsenic transport to groundwater. Thus, there is an essential requirement for understanding the retention capacity and mobility of arsenic in the soils to ensure sustainability of the groundwater in the locality. Arsenic interaction with various physicochemical properties of soil would provide a better understanding of its leaching from the soil. Materials and methods: Fifty-one soil samples were collected from two regions of Bathinda district with extensive agricultural practices, namely, Talwandi Sabo and Goniana. The soils were analyzed for arsenic content and related physicochemical characteristic of the soil which influence arsenic mobility in soil. Adsorption studies were carried out to identify the arsenic mobilization characteristic of the soil. SEM-EDX and sequential extraction of arsenic adsorbed soil samples affirmed the arsenic adsorption and its mobility in soil, respectively. Multiple regression models have been formulated for meaningful soil models for the prediction of arsenic transport behavior and understand the adsorption and mobilization of arsenic in the soil matrices. Results and discussion: Region-wise analysis showed elevated levels of arsenic in the soil samples from Goniana region (mean 9.58?mg?kg?1) as compared to Talwandi Sabo block (mean 3.38?mg?kg?1). Selected soil samples were studied for As(V) and As(III) adsorption behavior. The characteristic arsenic adsorption by these soil samples fitted well with Langmuir, Freundlich, Temkin, and D-R isotherm with a qmax in the range of 45 to 254?mg?kg?1 and 116 to 250?mg?kg?1 for As(III) and As(V), respectively. Adsorption isotherms indicate weak arsenic retention capacity of the soil, which is attributed to the sandy loam textured soil and excessive fertilizer usage in this region. PCM and MLR analysis of the soil arsenic content and its adsorption strongly correlated with soil physicochemical parameters, namely, Mn, Fe, total/available phosphorus, and organic matter. Conclusions: Manganese and iron content were firmly established for retention of arsenic in soil, whereas its mobility was influenced by organic matter and total/available phosphorus. The poor adsorptive characteristic of these soils is the primary cause of higher arsenic concentration in groundwater of this region. A strong correlation between monitored arsenic and adsorbed As(III) with manganese suggests As(III) as the predominant species present in soil environment in this region. ? 2015, Springer-Verlag Berlin Heidelberg.
Sorptive removal of arsenite [As(III)] and arsenate [As(V)] by fuller’s earth immobilized nanoscale zero-valent iron nanoparticles (F-nZVI): Effect of Fe 0 loading on adsorption activity
(Elsevier, 2016) Sharma, Archana Kumari; Babu, J. Nagendra; Yadav,Radheshyam
Fuller’s earth immobilized nanoscale zerovalent iron (F-nZVI 1–8) were synthesized by borohydride reduction method. The iron loading of fuller’s earth immobilized nZVI was varied from 5 to 50% (w/w) in these F-nZVI 1–8. The F-nZVI 1–8 were characterized by FE-SEM–EDX, FTIR, BET, XRD and TGA. The FE-SEM analysis showed an increase in agglomeration of nZVI on the immobilized material with increase in the loading of Fe0. F-nZVI 1–8 were studied for adsorptive removal of As(III) and As(V) from aqueous solution, with an emphasis on the effect of Fe0 loading of adsorbent on arsenic remediation. Iron loading has a significant role in adsorption of As(III) and As(V) on F-nZVI, with increase in adsorption with optimum iron loading of 20% (w/w) on fuller’s earth (F-nZVI-4). However, increase in loading above 20%, resulted in no significant increase in As(III) and As(V) adsorption. The adsorption results fitted well with Langmuir and Freundlich isotherm models and the maximum adsorption capacity of F-nZVI-4 for As(III) and As(V) were observed to be 50.08 and 91.42 mg/g, respectively. The adsorption isotherm and kinetic studies indicate a rapid removal of As(III) and As(V) from the aqueous solution in the presence of F-nZVI 1-8, with an substantially high rate of removal for arsenic with F-nZVI-4.
Synergistic effect of eco-friendly pistachio shell biomass on nano-MnO2 for crystal violet removal: kinetic and equilibrium studies
(Institute for Ionics, 2022-05-07T00:00:00) Kumar, S.; Brar, R. Singh; Saha, S.; Dahiya, A.; Kalpana; Babu, J. Nagendra
Pistachio shell powder-supported MnO2 nanostructure-based eco-friendly nanocomposite (nMPP) was prepared via one-pot redox precipitation method and was characterized by FTIR, XRD, SEM, TEM, BET, TGA/DTA, and XPS techniques. SEM and TEM analysis revealed the pseudo-spherical and nanorod morphologies of the synthesized nano-MnO2 and found agglomerated on the pistachio biomass. The nMPP contains nearly 41% Mn as MnO2 (w/w %) dispersed onto the pistachio shell biomass as confirmed from EDX, TGA, and AAS analysis. The nMPP exhibits multi-process crystal violet (CV) removal phenomenon under different pH of aqueous dye solution. Under acidic pH, nMPP caused oxidative degradation of CV by in situ formed.OH radicals; while under the neutral pH, CV undergoes monolayer adsorption onto the surface of nMPP as confirmed from Langmuir adsorption isotherm fit with maximum equilibrium adsorption value of 148.7�mg.g?1. The nMPP nanomaterial exhibits a synergistic effect between adsorption efficiencies of pistachio shell biomass and nano-MnO2 for the effective removal of toxic CV dye. The maximum saturation adsorption and rate constant (k 2) value obtained from the pseudo-second-order kinetic fit model were 119.13�mg.g?1 and 5.0 � 10�4�g.mg?1�min?1, respectively. Graphical abstract: [Figure not available: see fulltext.] � 2022, The Author(s) under exclusive licence to Iranian Society of Environmentalists (IRSEN) and Science and Research Branch, Islamic Azad University.
Synergistic effect of pistachio shell powder and nano-zerovalent copper for chromium remediation from aqueous solution
(Springer Science and Business Media Deutschland GmbH, 2021-07-06T00:00:00) Kumar, Sandeep; Brar, Ravinderdeep Singh; Babu, J. Nagendra; Dahiya, Amarjeet; Saha, Sandip; Kumar, Avneesh
Pistachio shell powder supported nano-zerovalent copper (ZVC@PS) material prepared by borohydride reduction was characterized using SEM, FTIR, XRD, TGA/DTA, BET, and XPS. SEM, XRD, and XPS revealed the nano-zerovalent copper to consist of a core-shell structure with CuO shell and Cu(0) core with a particle size of 40�100 nm and spherical morphology aggregated on PS biomass. ZVC@PS was found to contain 39% (w/w %) Cu onto the pistachio shell biomass. Batch sorption of Cr(VI) from the aqueous using ZVC@PS was studied and was optimized for dose (0.1�0.5 g/L), initial Cr(VI) concentration(1�20 mg/L), and pH (2�12). Optimized conditions were 0.1 g/L doses of sorbent and pH=3 for Cr(VI) adsorption. Langmuir and Freundlich adsorption isotherm models fitted well to the adsorption behavior of ZVC@PS for Cr(VI) with a pseudo-second-order kinetic behavior. ZVC@PS (0.1g/L) exhibits qmax for Cr(VI) removal up to 110.9 mg/g. XPS and other spectroscopic evidence suggest the adsorption of Cr(VI) by pistachio shell powder, coupled with reductive conversion of Cr(VI) to Cr(III) by ZVC particles to produce a synergistic effect for the efficient remediation of Cr(VI) from aqueous medium. Graphical abstract: [Figure not available: see fulltext.] � 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
Synthesis of in situ immobilized iron oxide nanoparticles (Fe3O4) on microcrystalline cellulose: Ecofriendly and recyclable catalyst for Michael addition
(John Wiley and Sons Ltd, 2021-09-21T00:00:00) Kumar, Bhupender; Reddy, Marri Sameer; Dwivedi, Kartikey Dhar; Dahiya, Amarjeet; Babu, J. Nagendra; Chowhan, L. Raju
Microcrystalline cellulose-immobilized Fe3O4 magnetic nanoparticles (Fe3O4@MCC) with iron loading 5%�20% are synthesized and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The synthesized nanocomposites were studied for their catalytic activity towards Michael addition reaction by employing 1,3-cyclohexadione/dimedone and styrylisoxazole in an aqueous ethanolic medium. The catalyst with 15% iron loading showed the highest efficiency with an excellent yield. Michael addition reaction is one of the most important reaction for the creation of a carbon�carbon bond and widely used in organic synthesis under mild condition. The prepared catalyst performed well in Michael addition reaction and afforded the product in excellent yield. The products were isolated by simple filtration without use of any chromatographic techniques. The scale-up experiment on 10-mmol scale proved the sustainability of the methodology. The catalyst was recycled, and the recovered catalyst data showed no considerable depreciation in catalytic activity even after 5 consecutive cycles. The advantages of this green and safe procedure include a simple reaction set-up, very mild reaction conditions, high yields, moderate reaction time, recyclable catalyst, and easy separation of the products without use of any tedious separation techniques. � 2021 John Wiley & Sons, Ltd.
Tetracycline removal via three-way synergy between pistachio shell powder, zerovalent copper or iron, and peroxymonosulfate activation
(Elsevier B.V., 2023-10-20T00:00:00) Kaur, Parminder; Kumar, Atul; Babu, J. Nagendra; Kumar, Sandeep
Pistachio shell powder (PS) immobilized zerovalent iron and zerovalent copper (ZVI@PS and ZVC@PS) were investigated for the tetracycline (TCH) removal via sulfate radical based advanced oxidation process (S-AOP's). Eco-efficient ZVI@PS and ZVC@PS nanocomposite prepared by one-pot redox precipitation method were characterized by using FTIR, XRD, SEM, BET, TGA/DTA, and XPS techniques. The EDX, TGA, and AAS analysis techniques confirmed the loading of 44 % Fe and 40 % Cu (w/w %) onto the pistachio shell biomass in ZVI@PS and ZVC@PS nanocomposites, respectively. This report comprehensively discusses the effect of various contributing factors for the TCH removal via advanced oxidation processes such as catalytic dosage, initial pH, PMS dosage and initial TCH concentrations, etc. Besides that, the role of reactive oxygen species (SO4?,.OH, O2?, and 1O2) in the TCH degradation process was investigated using radical scavenging experiments. A three-way synergistic approach was established between adsorption efficiencies of pistachio shell powder, heterogeneous ZVI or ZVC mediated Fenton-process and enhanced PMS activation process, for the observed enhanced TCH degradations. The observed rate constant (kobs.) values of ZVI@PS-PMS (0.34 min?1) and ZVC@PS-PMS (0.16 min?1) processes for TCH removal suggests that the ZVI@PS was more efficient in TCH removal compared to ZVC@PS. � 2023 The Author(s)