Browsing by Author "Dutta, S."

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3d nano capacitors using electrodeposited nickel nanowires in porous anodic alumina template
(Springer Science and Business Media, LLC, 2019) Viegas, A.E.; Dutta, S.; Rekha, S.; Bobji, M.S.; Raghavan, S.; Bhat, N.
We report the fabrication and characterization of a new design of 3D nano Capacitors using Alumina nanopores as the dielectric material. Nickel nanowires grown inside the nanopores act as high surface area electrodes. These wires are combined together in the form interdigitated capacitor structure, to achieve very high capacitance density. Â© Springer Nature Switzerland AG 2019.
5-(Halomethyl)furfurals
(Elsevier, 2025) Dutta, S.
5-(Halomethyl)furfurals, derived from biomass-derived carbohydrates, act as renewable platform chemicals for the sustainable synthesis of industrially important organic chemicals. The historical background, physicochemical properties, production routes, reactivity patterns, and derivative chemistry of 5-(halomethyl)furfurals developed over the past century can assist in better comprehending their pivotal roles in the carbohydrate-centric biorefinery for the sustainability of the chemical industry and circular carbon economy. © 2024 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
A comparative analysis of crustacean exoskeletons: structural, microstructural, morphological, and UV absorption studies
(Institute of Physics, 2024) Nowl, M.S.; Praveen, L.L.; Ambili, V.; Singh, S.; Samad, U.; Seikh, A.H.; Dutta, S.; Mandal, S.
This study aims to investigate the structural, thermal, and spectral characteristics, along with the ultra-violet (UV) absorption of various marine benthos exoskeletons, such as various species of crabs (Portunus sanguinolentus, Portunus pelagicus, Charybdis feriata) and mantis shrimp (Oratosquilla oratoria). Their unique properties and ability to survive in harsh oceanic environments make them interesting research subjects. This research utilized powder x-ray diffraction (XRD) analysis to determine the crystal structure of the benthic varieties. The sample surface was analyzed using high-resolution micrographs obtained from field-emission scanning electron microscopy (FESEM), which identified the presence of chitin and calcite in the marine benthos. This was further confirmed by differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR). The optical characteristics were investigated using UV-visible spectroscopy. The proximate analysis revealed high protein content in the mantis shrimp exoskeleton compared to other crab species, highlighting its excellent UV absorption characteristics. Overall, this research has the potential to broaden our understanding of marine organisms, which can have potential applications in biotechnology and materials science to develop nature-inspired innovative materials sustainably. © 2024 The Author(s). Published by IOP Publishing Ltd.
A Novel Single Source Bridgeless Nine-Level Switched-Capacitor-Based Quadruple Boost Inverter With Reduced Voltage Stress
(Institute of Electrical and Electronics Engineers Inc., 2024) Kumar, D.; Raushan, R.; Ahmad, M.W.; Dutta, S.
The attractiveness of switched capacitor multilevel inverters (SCMLIs) stems from their ability to operate without transformers, providing voltage-boosting capabilities, inherent capacitors' voltage balancing ability, and reduced electromagnetic interference. Recent developments in SCMLI structures make it a compelling choice among various converters for diverse applications. The evolution of these topologies is primarily influenced by factors such as the number of output voltage levels, overall voltage gain, and the simultaneous reduction of component counts and stresses on devices. To address these issues further, a novel bridgeless common neutral switched capacitor multilevel inverter has been proposed in this article. The maximum voltage stress on the devices is just half of the peak output voltage, and the total standing voltage is also lower in this inverter. It has quadruple voltage gain and inherent voltage balancing of the switched capacitors. Additionally, it can operate under various loads and modulation indexes. Moreover, the proposed inverter's leakage current can be almost zero due to the presence of the common ground (CG) feature. The nearest level pulse width control technique has been implemented to operate the proposed inverter. Comparative analysis was carried out to show the advantages of the inverter. Further, a hardware prototype of the experimental setup has been developed, and results have been analyzed and discussed to strengthen the performance of the proposed inverter. © 2013 IEEE.
A roadmap to UV-protective natural resources: Classification, characteristics, and applications
(Royal Society of Chemistry, 2021) P, P.; Salian, A.; Dutta, S.; Mandal, S.
Alongside the innumerable benefits of solar rays, the adverse effects of ultraviolet (UV) radiation must be considered. All organisms are subjected to the deleterious effects of UV radiation, particularly UVA (315-400 nm) and UVB (280-315 nm). Continuous UV exposure leads to skin cancer, erythema, and sunburn mediated by reactive oxygen species (ROS). Photoprotection is hence an indispensable feature in all strata of the ecosystem across the microbial, plant, and animal kingdoms, especially under the present circumstance of increased ozone depletion. Photoprotective compounds, like gadusols, mycosporine-like amino acids (MAAs), scytonemin, phenolic compounds like flavonoids, anthocyanins, lignin, and less-explored compounds like sporopollenin, parietin, and usnic acid have been identified in various organisms. Accumulation of photoprotective pigments is a universal mechanism of passive protection against UV, developed by organisms during the early stages of their evolution. Furthermore, many of these compounds contribute to antioxidant and anti-inflammatory actions, which offer additional protection. In this review, the attributes of naturally available UV-screening compounds are investigated. Their taxonomic diversity, mechanism of UV absorption, extraction, and characterization techniques are discussed. In the wake of recent studies that indicate free radical generation in inorganic sunscreen compounds like TiO2 and ZnO, natural products have become a necessity. Insights into natural compounds for photoprotective functions in commercial applications like cosmetics and textiles are also reviewed. Biocompatibility and minimal side effects of these natural compounds open the gateway into an era of green products in the arena of photoprotection. © the Partner Organisations.
A scalable and high-yielding synthesis of 2-(2-furyl)-1,3-dioxolane from biomass derived furfural and ethylene glycol using heteropoly acids as green catalyst
(Chemical Publishing Co., 2019) Tiwari, R.; Mal, S.S.; Dutta, S.
In present work, Keggin-type commercial heteropoly acids have been employed as efficient solid acid catalysts in the acetalization of biomass-derived furfural with ethylene glycol. The reaction was optimized on parameters such as the type and loading of catalyst, duration of reaction and the relative ratio of reagents. The reaction was scaled up and the cyclic acetal 2-(furan-2-yl)-1,3-dioxolane was isolated in 92 % yield within 4 h using only 2 wt % of phosphotungstic acid in refluxing benzene. © 2019 Chemical Publishing Co.. All rights reserved.
A straightforward preparation of levulinic esters from biorenewable levulinic acid using methanesulfonic acid supported on silica gel (MSA-SG) as an efficient heterogeneous catalyst
(Elsevier Ltd, 2023) Vinod, N.; Bandibairanahalli Onkarappa, S.; Madhwaraj Girija, V.; Dutta, S.
The present work reports methanesulfonic acid supported on silica gel (MSA-SG) as an inexpensive heterogeneous solid acid catalyst for the high-yielding production of various alkyl levulinates from biomass-derived levulinic acid. The catalyst was characterized by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX). The reactions were conducted in a batch-type glass pressure reactor under conventional heating. The esterification reaction was optimized on temperature, duration, and catalyst loading. The optimized reaction conditions (120 Â°C, 8 h, 8 wt% MSA-SG) afforded methyl- to butyl levulinate in excellent isolated yields (â‰¥90 %). The catalyst was filtered, and the products were purified by simply evaporating the excess alcohol reagent. Â© 2022
Activated Carbon from Cashew Nut Husk and Cashew Nut Shell Wastes: Synthesis, Characterization, and Adsorption Studies
(John Wiley and Sons Inc, 2023) Anchan, H.N.; Jadhav, S.; Dutta, S.
Activated carbon (AC) is a key material in numerous industrial applications, including wastewater treatment, catalysis, personal care products, and pharmaceutical industry. Producing AC from waste biomass is of much interest since the environmental footprint is low and the economics are favorable for most applications. Cashew nut husk (CNH) and cashew nut shell (CNS) are typically considered wastes in the cashew nut processing industry. Synthesis of AC from CNH and CNS allows value addition of these materials and improves the economic prospects of the cashew nut processing industry. Herein, we report the production of AC by carbonization of CNH and CNS using orthophosphoric acid as the activating agent. The results showed that 700 °C is a suitable activation temperature for CNH, whereas 500 °C was enough for activating CNS. The AC samples were extensively characterized by FTIR, PXRD, BET, and FESEM-EDX analysis. The AC produced from CNH at 700 °C (H-700) exhibited a very high specific surface area and iodine number of 1511 m2/g and 961 mg/g, respectively. Therefore, H-700 was used for adsorbing methylene blue from water as a model for wastewater treatment. The H-700 sample showed an adsorption capacity of 520 mg/g with good recyclability up to five cycles. © 2023 Wiley-VCH GmbH.
Aqueous solution of biogenic carboxylic acids as sustainable catalysts and green reaction media for the high-yielding synthesis of Biginelli adducts, Hantzsch esters, and substituted pyridines
(Royal Society of Chemistry, 2024) Prabhakar, P.S.; Sahoo, J.; Alnaser, I.A.; Seikh, A.H.; Karim, M.R.; Dutta, S.
3,4-Dihydropyrimidin-2(1H)-ones (DHPMs) and 1,4-dihydropyridines (DHPs), prepared by applying the Biginelli and Hantzsch reaction protocols, respectively, are well-documented nitrogen-containing heterocycles with intriguing pharmacological properties. The aqueous solution of biogenic carboxylic acids renewably produced from biomass via catalytic or enzymatic processes can be used as a sustainable catalyst and green reaction media for synthesizing DHPs and DHPMs. This work evaluates the efficacy of various biogenic acids in their aqueous solutions as catalysts for synthesizing DHPs and DHPMs from substituted benzaldehydes. Among the studied biogenic acids, gluconic acid aqueous solution (GAAS) proved to be the most efficient, safe, non-volatile, and recyclable catalyst. The reaction afforded excellent isolated yields (≥85%) of spectroscopically pure DHPs and DHPMs under optimized conditions and employed a straightforward work-up procedure. Aqueous ammonia was successfully employed instead of ammonium salt to improve the atom economy of DHPs. Moreover, substituted pyridines were synthesized from DHPs in a one-pot, two-step process using NaNO2 as an oxidant in the GAAS medium. This journal is © The Royal Society of Chemistry, 2024
Biomass-derived 5-(tolylmethyl)furfural as a promising diesel additive: preparation, process scale-up, and engine studies
(Royal Society of Chemistry, 2025) Yadav, A.K.; Yadav, S.K.; Kumar, G.N.; Madav, V.; Dutta, S.
Furanic fuel oxygenates, renewably produced from biomass, have received significant interest in lessening dependence on petroleum-derived liquid fuels and reducing emissions. 5-(Tolylmethyl)furfural (TMF) was prepared by the Friedel-Crafts reaction between cellulose-derived 5-(acetoxymethyl)furfural (AcMF) and petroleum-derived toluene. The process was optimized on various parameters, such as reaction temperature, molar ratio of reagents, catalyst loading, and duration. Anhydrous ZnCl2 was the best catalyst for the reaction, affording a 67% isolated yield of TMF under optimized conditions (120 °C, 4 h). TMF was prepared on a 30 g scale and blended (1-5 vol%) with diesel. The physicochemical properties of the TMF-diesel blended fuel mixtures were studied, and then they were employed as fuel for a direct injection single-cylinder diesel engine. The results show good fuel properties and reduced emissions compared to unblended diesel fuel. © 2025 The Royal Society of Chemistry.
Biomass-Derived Reaction Media Towards the Iodination of Anilines Under the Catalytic Influence of Magnetically Separable Pd@rGO-CuFe2O4
(Bentham Science Publishers, 2025) Reetu, R.; Teli, Y.A.; Patel, M.J.; Keremane, K.S.; Dutta, S.; Malakar, C.C.; Almeer, R.
Investigation of a biomass-derived solvent, such as ?-valerolactone (GVL), for the iodination of anilines was devised. The process is accomplished under the catalytic influence of a magnetically separable Pd@rGO-CuFe2O4catalyst (with 0.00047 mol% Pd loading) at 25°C. The catalyst is recovered from the reaction medium using an external magnet and recycled for five consecutive reaction cycles with very minor catalyst leaching. The developed strategy has been thoroughly studied over a series of starting materials to obtain the iodoaniline derivatives, and the desired products were obtained effectively in yields up to 91% with high regioselectivity. A plausible reaction mechanism was proposed based on previous findings. This method has been extended to gram-scale synthesis with a 76% yield of the desired product. © 2025 Bentham Science Publishers
Catalytic conversion of biomass-derived carbohydrates into levulinic acid assisted by a cationic surface active agent
(John Wiley and Sons Inc, 2019) Onkarappa, S.B.; Bhat, N.S.; Parashuram, D.; Dutta, S.
Levulinic acid (LA), a bio-renewable chemical building block, has been produced in good isolated yields by treating biomass-derived carbohydrates with aqueous hydrochloric acid in the presence of quaternary ammonium salts as cationic surface-active agent (SAA). Under optimized conditions (120 °C, 3 h, 20.2% HCl), the one-pot process afforded LA in 80% isolated yield from glucose using only 5.77mol% (10 wt%) of benzyl-tributylammonium chloride (BTBAC) at the SAA. The control reaction (no BTBAC) provided LA in only 64% yield from glucose under identical conditions. The process was optimized on the reaction temperature, loading of BTBAC, and the concentration of HCl. The use of BTBAC led to a nearly 8–17% increase in yield of LA (compared to the control reaction) for all the carbohydrates studied. © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Catalytic conversion of glucose and its biopolymers into renewable compounds by inducing C–C bond scission and formation
(Springer Science and Business Media Deutschland GmbH, 2024) Anchan, H.N.; Bhat, N.S.; Vinod, N.; Prabhakar, P.S.; Dutta, S.
Transportation fuels and chemicals can be produced renewably by selectively altering the carbon skeleton of biomass-derived glucose. The predominantly catalytic processes incorporate carbon–carbon (C–C) bond scission and formation reactions with concomitant defunctionalization and refunctionalization steps. The production and synthetic upgrading of various biochemicals achieved by the C–C bond-scission (C1–C5) and C–C bond-forming (> C6) reactions from glucose and its biopolymers (e.g., starch, cellulose) have been reviewed. The details of transforming glucose and its polymers into targeted biochemicals, such as mechanistic pathway, process parameters, product selectivity, and specifics of the catalysts employed, have been elaborated. The interconversions of these chemicals of commercial significance under catalytic conditions are also highlighted. This review will assist the researchers in comprehending this field from a distinct perspective, reassess the challenges, identify the research gaps, and critically appraise the emerging research avenues. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2022.
Catalytic synthesis of renewable chemicals from carbohydrates following pot, atom, and step-economy (PASE): An overview
(Elsevier Ltd, 2025) Dutta, S.
Pot, atom, and step-economy (PASE) help to improve the sustainability of synthesizing organic chemicals by reducing capital and operational expenditure, optimizing energy and materials input, and minimizing waste generation. Applying PASE to the catalytic conversion of biomass-derived carbohydrates into renewable organic chemicals could offer substantial societal, economic, and environmental incentives. This review article overviews recent developments in synthesizing selected high-value chemicals (e.g., furanics, alcohols, carboxylic acids, and esters) from biomass-derived carbohydrates following PASE. The discussion on catalysts, reaction parameters, mechanistic insights, and green metrics for specific biorenewable chemicals came intuitively. Competitive synthetic routes of carbohydrate-derived chemicals have been evaluated based on green metrics, influences of PASE on their commercial prospects have been highlighted, and future research directions have been proposed for the sustainable functioning of a carbohydrate-centric biorefinery. © 2025 Elsevier Ltd
Catalytic synthesis of renewable p-xylene from biomass-derived 2,5-dimethylfuran: a mini review
(Springer Science and Business Media Deutschland GmbH, 2023) Dutta, S.; Bhat, N.S.
In this work, the renewable synthesis of p-xylene (PX) from biomass-derived carbohydrates has been reviewed. PX is a crucial chemical feedstock and an essential starting material of polyethylene terephthalate (PET). PX can be produced selectively by the Diels-Alder reaction between ethylene and 2,5-dimethylfuran (DMF) followed by catalytic dehydration of the oxanorbornene adduct. DMF is primarily produced by the catalytic hydrogenation of 5-(hydroxymethyl)furfural (HMF), a furanic intermediate produced by the acid-catalyzed hydrolysis/dehydration of biomass-derived hexoses. With ethylene being sourced by dehydrating bioethanol, PET can be made biorenewable in its entirety. The atom economy and carbon efficiency of converting glucose into PX have been calculated. The existing literature (both theoretical and experimental) on the catalytic production of PX from DMF and ethylene are summarized, and future directions on this research have been proposed. The effect of Brønsted and Lewis acidity, porosity, and surface area of the heterogeneous catalysts on the selectivity and yield of PX have been highlighted. In addition, the techno-economic analysis of renewable PET, its future prospects based on the petroleum market, and the possibility of a circular economy of PET using chemical and enzymatic recycling strategies have been discussed. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
Catalytic Transformation of Biomass into Sustainable Carbocycles: Recent Advances, Prospects, and Challenges
(John Wiley and Sons Inc, 2025) Dutta, S.
Organic compounds bearing one or more carbocycles in their molecular structure have a discernible presence in all major classes of organic products of industrial significance. However, sourcing carbocyclic compounds from exhaustible, anthropogenic carbon (e. g., petroleum) raises serious concerns about sustainability in the chemical industries. This review discusses recent advances in the renewable synthesis of carbocyclic compounds from biomass components following catalytic pathways. The mechanistic insights, process optimizations, green metrics, and alternative synthetic strategies of carbocyclic compounds have been detailed. Moreover, the renewable syntheses of carbocycles have been assessed against their existing synthetic routes from petroleum for better perspectives on their sustainability and technological preparedness. This work will assist the researchers in acquiring updated information on the sustainable synthesis of carbocyclic compounds from various biomass components, comprehending the research gaps, and developing superior synthetic processes for their commercial production. © 2024 Wiley-VCH GmbH.
Catalytic Transformation of Biomass-Derived Furfurals to Cyclopentanones and Their Derivatives: A Review
(American Chemical Society, 2021) Dutta, S.; Bhat, N.S.
Furfural (FF) and 5-(hydroxymethyl)furfural (HMF) are well-recognized biomass-derived chemical building blocks with established applications and markets for several of their derivatives. Attaining a wide spectrum of petrochemicals is the primary target of a biorefinery that employs FF and HMF as the chemical feedstock. In this regard, cyclopentanone (CPN) is a crucial petrochemical intermediate used for synthesizing a diverse range of compounds with immense commercial prospects. The hydrogenative ring rearrangement of FF to CPN in an aqueous medium under catalytic hydrogenation conditions was first reported in 2012, whereas the first report on the catalytic conversion of HMF to 3-(hydroxymethyl)cyclopentanone (HCPN) was published in 2014. Over the past decade, several investigations have been undertaken in converting FF and HMF to CPN and HCPN, respectively. The research studies aimed to improve the scalability, selectivity, environmental footprint, and cost competitiveness of the process. A blend of theoretical and experimental studies has helped to develop efficient, inexpensive, and recyclable heterogeneous catalysts that work under mild reaction conditions while providing excellent yields of CPN and HCPN. The time is ripe to consolidate the data in this area of research and analyze them rigorously in a review article. This work will assist both beginners and experts of this field in acknowledging the accomplishments to date, recognize the challenges, and strategize the way forward. © 2021 The Authors. Published by American Chemical Society.
Catalytic Transformation of Carbohydrates into Renewable Organic Chemicals by Revering the Principles of Green Chemistry
(American Chemical Society, 2024) Dutta, S.
Adherence to the principles of green chemistry in a biorefinery setting ensures energy efficiency, reduces the consumption of materials, simplifies reactor design, and rationalizes the process parameters for synthesizing affordable organic chemicals of desired functional efficacy and ingrained sustainability. The green chemistry metrics facilitate assessing the relative merits and demerits of alternative synthetic pathways for the targeted product(s). This work elaborates on how green chemistry has emerged as a transformative framework and inspired innovations toward the catalytic conversion of biomass-derived carbohydrates into fuels, chemicals, and synthetic polymers. Specific discussions have been incorporated on the judicious selection of feedstock, reaction parameters, reagents (stoichiometric or catalytic), and other synthetic auxiliaries to obtain the targeted product(s) in desired selectivity and yield. The prospects of a carbohydrate-centric biorefinery have been emphasized and research avenues have been proposed to eliminate the remaining roadblocks. The analyses presented in this review will steer to developing superior synthetic strategies and processes for envisaging a sustainable bioeconomy centered on biomass-derived carbohydrates. © 2024 The Author. Published by American Chemical Society.
Characterization and upgradation of crude tire pyrolysis oil (CTPO) obtained from a rotating autoclave reactor
(Elsevier Ltd, 2019) Mohan, A.; Dutta, S.; Madav, V.
Many of the inferior fuel properties of crude tire pyrolysis oil (CTPO) can be attributed to the presence of polar organic compounds such as various oxygenates, nitrogen heterocycles and sulfur-containing compounds. An efficient, straightforward and scalable pathway of removing the polar fraction from CTPO is crucial in improving its fuel properties. In this work, CTPO produced by thermal pyrolysis (400 °C, 0.2 bar, 4 rpm, 5 h) of scrap automotive tires in a rotating autoclave reactor (8-tons) has been upgraded using silica gel (60–120 mesh) as adsorbent and petroleum ether as diluent. In two different strategies, CTPO was first diluted with petroleum ether and (1) passed through a column of silica gel (CoTPO) or (2) mechanically stirred with silica gel (StTPO) followed by solvent evaporation to afford upgraded oil. Both crude and upgraded TPO samples were extensively analyzed for chemical composition and fuel properties and compared with each other. Analytical techniques like GC–MS, 1H NMR, FTIR, and elemental analysis showed significantly less polar fractions in CoTPO and StTPO compared to CTPO. The cetane index of CoTPO and StTPO were found to be 35 and 40, respectively compared to 33 in CTPO. Sulfur content decreased by 19% and 34% in CoTPO and StTPO, respectively. The acid value of CoTPO and StTPO were found to be 0.8 and 0.6 compared to 12.2 in CTPO. The TGA data showed better thermal stability of upgraded oil samples. StTPO showed better chemical composition and fuel properties compared to CoTPO that can be explained by its longer contact time with silica gel adsorbent. © 2019 Elsevier Ltd
Chemocatalytic value addition of glucose without carbon-carbon bond cleavage/formation reactions: an overview
(Royal Society of Chemistry, 2022) Dutta, S.; Bhat, N.S.
As the monomeric unit of the abundant biopolymer cellulose, glucose is considered a sustainable feedstock for producing carbon-based transportation fuels, chemicals, and polymers. The chemocatalytic value addition of glucose can be broadly classified into those involving C-C bond cleavage/formation reactions and those without. The C6 products obtained from glucose are particularly satisfying because their syntheses enjoy a 100% carbon economy. Although multiple derivatives of glucose retaining all six carbon atoms in their moiety are well-documented, they are somewhat dispersed in the literature and never delineated coherently from the perspective of their carbon skeleton. The glucose-derived chemical intermediates discussed in this review include polyols like sorbitol and sorbitan, diols like isosorbide, furanic compounds like 5-(hydroxymethyl)furfural, and carboxylic acids like gluconic acid. Recent advances in producing the intermediates mentioned above from glucose following chemocatalytic routes have been elaborated, and their derivative chemistry highlighted. This review aims to comprehensively understand the prospects and challenges associated with the catalytic synthesis of C6 molecules from glucose. This journal is © The Royal Society of Chemistry