Faculty Publications
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Publications by NITK Faculty
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Item Oxidation and Reduction of Biomass-Derived 5-(Hydroxymethyl)furfural and Levulinic Acid by Nanocatalysis(American Chemical Society, 2020) Dutta, S.; Bhat, N.S.; Vinod, N.Nanocatalysis combines the advantageous characteristics of both homogenous and heterogeneous catalysis while reducing their respective drawbacks. In recent years, nanocatalysts are increasingly being used in the chemical-catalytic conversion of biomass into value-added fuels and specialty chemicals. 5-(Hydroxymethyl)furfural (HMF) and levulinic acid (LA) are well-documented biomass-derived chemical intermediates that can be synthetically modified into products of commercial significance. Nanocatalysts have played a crucial role in the selective oxidation and reduction of HMF and LA into high-value compounds. In some cases, nanocatalysts provide selectivity and reactivity under relatively mild reaction conditions that could not be achieved by conventional homogeneous or heterogeneous catalysts. Over the years, a thorough understanding of the size-dependent properties of nanoparticles, the interactions among various components of catalysts including support materials, and the interactions of starting materials or products with the catalytic materials have helped in fine-tuning the new generation of nanocatalysts for unprecedented reactivities and selectivities toward the products of interest. In this chapter, the use of nanocatalysts for the selective oxidation and reduction of HMF and LA into valuable chemicals is elaborated, and the future prospects of nanocatalysts in this area are appraised. © 2020 American Chemical Society.Item Nanocatalysis for renewable aromatics(wiley, 2022) Dutta, S.; Bhat, N.S.; Anchan, H.N.Chemocatalytic transformation of biomass feedstock, especially the non-food, inexpensive, and abundant terrestrial lignocellulose into fuels and chemicals, has multifaceted benefits, including the development of a sustainable economy and a cleaner environment. Aromatic compounds have a ubiquitous presence in the chemical industry. They must be accessed from biomass to supplant the same from fossilized resources. Several pathways have been developed to convert the major biomass components into aromatic hydrocarbons and functionalized aromatic compounds by catalytic methods. In this regard, heterogeneous nanocatalysts (NCs) have received particular attention since they have many superior properties, such as better selectivity, faster kinetics, and the requirement of lower loading due to higher activity, compared to the traditional heterogeneous catalysts of the micrometer scale. Polymeric carbohydrates like cellulose can be converted into furanic compounds first, which were then converted to benzene derivatives. The lignin fraction can be deconstructed into phenolics or further reduced into mononuclear aromatic hydrocarbons. Direct conversion of biomass into bio-oil containing aromatics is an alternative option. This chapter attempts to divulge the major pathways available to convert various biomass components into aromatic compounds emphasizing on the use of NCs for the chemical transformations. The accomplishments made to date and the challenges ahead are also emphasized. © 2023 John Wiley & Sons Ltd.Item 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.Item 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. © Springer Nature Switzerland AG 2019.Item Co-pyrolysis of scrap tire and plastic using coal derived fly-ash(ETA-Florence Renewable Energies, 2019) Mohan, A.; Dutta, S.; Madav, V.; Bhushnoor, S.S.; Fernandez-Garcia, J.F.; Williams, P.T.Used automobile tires and thermoplastics (e.g. polypropylene) have become liability of modern societies and several avenues have been explored for their suitable disposal. Pyrolytic liquefaction of tires and plastics have attracted significant attention since the process can provide value-added products such as liquid transportation fuels and chemicals while mitigating the waste disposal issues. Pyrolysis can be done both in absence (thermal) or presence (catalytic) of a catalyst. Catalytic pyrolysis is favored by less demanding reaction conditions and better quality of product. Catalytic copyrolysis has the additional advantage in using a wider feedstock and a possible synergistic effects from different feeds during molecular transformations. This work investigates the effect of untreated fly-ash (class F) as catalyst for the copyrolysis of scrap tire and polypropylene at 300o C and atmospheric pressure using batch type pyrolysis reactor and also studied the effect of fly-ash during pyrolysis of scrap tire using Pyro-GC/MS. Copyrolysis was carried out using various ratio of scrap tire and polypropylene at 300o C, whereas the pyrolysis of scrap tire in pyro-GC/MS was carried out at 500o C. The maximum yield (23.33%) of oil was obtained at a ratio of 60:40 (w/w) of scrap tire and polypropylene in presence of 20wt% of fly ash catalyst. The oils were characterized by NMR, GC-MS, FT-IR and elemental analysis. © 2019 ETA-Florence Renewable Energies.Item Straightforward synthesis of calcium levulinate from biomass-derived levulinic acid and calcium carbonate in egg-shells(Elsevier Ltd, 2019) Sharath, B.O.; Tiwari, R.; Mal, S.S.; Dutta, S.Calcium levulinate (CL) is a nutritional supplement for calcium and a chemical intermediate in synthesizing levulinic biofuels. The reported synthesis of CL involve reaction between cellulose-derived levulinic acid (LA) and calcium hydroxide in an aqueous medium. In this work, we report the production of CL using CaCO3 from poultry egg shells. The scalable production uses biomass-derived LA and egg-shell derived CaCO3 under conventional heating and mechanical stirring. The reaction was optimized on temperature, duration of reaction, and equivalent of CaCO3. Using 1.5 equivalent of CaCO3, the reaction completed within 2h at 50°C and afforded up to 97% isolated yield of CL as a crystalline solid. The reaction was also successfully carried out under mechanical grinding and scaled up to 20 g. The purity of the product was confirmed by melting point, FTIR, 1H-NMR and 13C-NMR spectroscopy. © 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Conference on Advanced Materials, Energy & Environmental Sustainability, ICAMEES2018Item The hydrogen peroxide-mediated oxidation of biorenewable furfural to 2(5H)-furanone using heteropolyacids supported on ammonium y zeolite as the catalyst(Elsevier Ltd, 2020) Tiwari, R.; Bhat, N.S.; Mal, S.S.; Dutta, S.A series of heteropolyacid supported on ammonium Y zeolite (HPA-NH4YZ) catalysts were prepared and used for the catalytic oxidation of furfural to 2(5H)-furanone in aqueous hydrogen peroxide. The catalysts were characterized by PXRD, FTIR, TGA, and SEM analyses. The organic-solvent-free reaction was optimized on temperature, duration, loading of catalyst, and the equivalent of H2O2. The 20%PTA-NH4YZ catalyst showed the best catalytic activity giving 2(5H)-furanone in 40% isolated yield by solvent extraction under optimized conditions (20wt% cat., 100°C, 90min, 7.5eq. 30%H2O2). In addition, around 20% of succinic acid was recovered from the aqueous layer. © 2020 Elsevier Ltd. All rights reserved.Item High-yielding synthesis of alkyl stearates from stearic acid within a closed batch reactor using heteropolyacids as efficient and recyclable catalyst(American Institute of Physics Inc. subs@aip.org, 2020) Vinod, N.; Tiwari, R.; Bhat, N.S.; Mal, S.S.; Dutta, S.This study reports high-yielding and scalable synthesis of alkyl stearates from stearic acid (SA) within a closed batch reactor using commercially-available heteropolyacid catalysts. The reaction was carried out by using different commercially-available heteropolyacids and reaction conditions were optimized by using phosphotungstic acid (PTA) catalyst. The solvent-free, gram-scale reactions afforded alkyl stearates in excellent isolated yields (>95%) within 4?h at 110 °C using slight excess of alcohols and only 1?mol% of the phosphotungstic acid (PTA) catalyst. The PTA catalyst was successfully recovered and reused for five consecutive cycles without significant loss in mass or activity. © 2020 Author(s).Item Quantum Machine Learning: A Review and Current Status(Springer Science and Business Media Deutschland GmbH, 2021) Mishra, N.; Kapil, M.; Rakesh, H.; Anand, A.; Mishra, N.; Warke, A.; Sarkar, S.; Dutta, S.; Gupta, S.; Prasad Dash, A.; Gharat, R.; Chatterjee, Y.; Roy, S.; Raj, S.; Kumar Jain, V.; Bagaria, S.; Chaudhary, S.; Singh, V.; Maji, R.; Dalei, P.; Behera, B.K.; Mukhopadhyay, S.; Panigrahi, P.K.Quantum machine learning is at the intersection of two of the most sought after research areas—quantum computing and classical machine learning. Quantum machine learning investigates how results from the quantum world can be used to solve problems from machine learning. The amount of data needed to reliably train a classical computation model is evergrowing and reaching the limits which normal computing devices can handle. In such a scenario, quantum computation can aid in continuing training with huge data. Quantum machine learning looks to devise learning algorithms faster than their classical counterparts. Classical machine learning is about trying to find patterns in data and using those patterns to predict further events. Quantum systems, on the other hand, produce atypical patterns which are not producible by classical systems, thereby postulating that quantum computers may overtake classical computers on machine learning tasks. Here, we review the previous literature on quantum machine learning and provide the current status of it. © 2021, Springer Nature Singapore Pte Ltd.Item 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 °C, 8 h, 8 wt% MSA-SG) afforded methyl- to butyl levulinate in excellent isolated yields (≥90 %). The catalyst was filtered, and the products were purified by simply evaporating the excess alcohol reagent. © 2022