01645nas a2200145 4500008004100000245014200041210006900183260000800252300001200260490000700272520105300279100002201332700002201354856012301376 2018 eng d00aEffect of structural properties of organosolv lignins isolated from different rice husks on their liquefaction using acidic ionic liquids0 aEffect of structural properties of organosolv lignins isolated f cMAY a739-7500 v203 aLignin is the only naturally available sustainable resource of aromatic compound on the Earth. Depending on the properties of lignin and the reaction conditions employed for the liquefaction, it is observed that the product distribution alters. Since ionic liquids (ILs) are considered as green and have tuneable properties, in the current work, imidazolium-based acidic ILs were employed to liquefy organosolv lignins derived from different varieties of rice husks. When liquefaction was carried out at 120 A degrees C for 1 h 36% yield for EtOAc- and DEE-soluble products with high mass balance (97 +/- 3%) was observed. The detailed characterisations of lignins and organic solvent-soluble products were done by variety of techniques [GC-MS, FT-IR, UV-Vis, 2D (HSQC) NMR], and based on this, the correlation between activity and properties of catalyst and lignin was established. Depolymerisation of organosolv lignin (derived from three rice husks) into aromatic product was done, and experimental correlation studies were performed in both. 1 aSingh, Sandip, K.1 aDhepe, Paresh, L. uhttps://library.ncl.res.in/content/effect-structural-properties-organosolv-lignins-isolated-different-rice-husks-their01364nas a2200157 4500008004100000022001500041245014900056210006900205260000800274300001400282490000600296520074000302100002001042700002201062856012201084 2018 eng d a 2044-475300a Efficient method for cyclopentanone synthesis from furfural: understanding the role of solvents and solubility in a bimetallic catalytic system0 aEfficient method for cyclopentanone synthesis from furfural unde cOCT a5259-52690 v83 aThe platform chemical, furfural (FAL), is obtained from C5 stream of biomass, and effective conversion into various chemicals including cyclopentanone (CPO) would find many industrial applications. It is desirable to convert FAL to CPO under low H-2 pressure with high selectivity. In the current work, bimetallic catalysts with Pt as the base metal supported on carbon are evaluated in the synthesis of CPO using a biphasic solvent system. By tuning the solvent ratio, with toluene/water (3:4 v/v), 75% yield of CPO is achieved under 1 MPa H-2 at 180 degrees C. The difference in solubility of the substrate, intermediates and products, along with the optimum ratio of Pt and Co metals plays a crucial role in achieving better yields.1 aDohade, Manisha1 aDhepe, Paresh, L. uhttps://library.ncl.res.in/content/efficient-method-cyclopentanone-synthesis-furfural-understanding-role-solvents-and01584nas a2200145 4500008004100000245013400041210006900175260000800244300001200252490000800264520099100272100002201263700002201285856013101307 2018 eng d00a Experimental evidences for existence of varying moieties and functional groups in assorted crop waste derived organosolv lignins0 aExperimental evidences for existence of varying moieties and fun cSEP a144-1510 v1193 aIsolation of organosolv lignins (ORGLs, water:ethanol, 180 degrees C, 1 h, 93 +/- 5% mass balance) from various lignocellulosic materials like rice husk (RH), wheat straw (WS), bagasse (BG) & wood chips (WC) was done and experimental evidences are provided to perceive the differences in the structures of isolated lignins. To achieve this on bulk level, lignins were characterized by XRD, GPC, TGA & elemental analysis and on molecular level using UV-vis, ATR, 1D/2D HSQC NMR techniques. Besides isolated lignins, crop wastes and pulps were also characterized to divulge details on their properties. It was revealed that lignins have varying concentrations of sinapyl (S), coniferyl (G) and p-coumaryl alcohols (H) and tricin (T) moieties. While, Tricin (T) type lignin moieties are observed only in RH and WS derived lignins, RH derived lignin has higher concentration of side chains than other isolated lignins. Additionally, it is discovered that most lignins have G as main moiety.1 aSingh, Sandip, K.1 aDhepe, Paresh, L. uhttps://library.ncl.res.in/content/experimental-evidences-existence-varying-moieties-and-functional-groups-assorted-crop-waste01530nas a2200217 4500008004100000022001400041245014900055210006900204260000900273300001100282490000800293520071800301653004301019653001701062653002301079653001101102653003001113100002201143700002201165856012501187 2021 eng d a1566-736700aEfficient catalytic transfer hydrogenation-hydrodeoxygenation of lignin derived monomers: investigating catalyst properties-activity correlation0 aEfficient catalytic transfer hydrogenationhydrodeoxygenation of  cJAN  a1062200 v1493 a

Reduction of O/C ratio of lignin derived monomers via hydrodeoxygenation (HDO) pathway is conventionally furnished using molecular hydrogen under severe conditions. Nonetheless, due to a prerequisite to accomplish HDO through commercially attractive methodology we report, HDO reactions of various phenolic compounds via catalytic transfer hydrogenation (CTH) pathway using very low loading of Ru (0.5 wt%) on neutral and acidic Al2O3 under nitrogen atmosphere. With guaiacol as a substrate, 74% cyclohexanol yield at 225 degrees C in the presence of IPA is realized. Bi-functionality of metal state, acidity of support and nature of alcohol are perceived to be responsible for the variation in activity.

10aCatalytic transfer hydrogenation (CTH)10aCyclohexanol10aHydrodeoxygenation10alignin10aSupported metal catalysts1 aSingh, Dheerendra1 aDhepe, Paresh, L. uhttps://library.ncl.res.in/content/efficient-catalytic-transfer-hydrogenation-hydrodeoxygenation-lignin-derived-monomers11157nas a2200217 45000080041000000220014000412450135000552100069001902600008002593000011002674900008002785201038200286653002410668653001810692653001810710653001010728653001910738100002110757700002210778856013910800 2021 eng d a0008-621500aElucidating the effect of solid base on the hydrogenation of C5 and C6 sugars over Pt–Sn bimetallic catalyst at room temperature0 aElucidating the effect of solid base on the hydrogenation of C5  cJUL a1083410 v5053 a

Conversion of sugars into sugar alcohols at room temperature with exceedingly high yields are achieved over Pt–Sn/γ-Al2O3 catalyst in the presence of calcined hydrotalcite. pH of the reaction mixture significantly affects the conversion and selectivity for sugar alcohols. Selection of a suitable base is the key to achieve optimum yields. Various solid bases in combination with Pt–Sn/γ-Al2O3 catalysts were evaluated for hydrogenation of sugars. Amongst all combinations, the mixture (1:1 wt/wt) of Pt–Sn/γ-Al2O3 and calcined hydrotalcite showed the best results. Hydrotalcite helps to make the pH of reaction mixture alkaline at which sugar molecules undergo ring opening. The sugar molecule in open chain form has carbonyl group which can be polarized by Sn in Pt–Sn/γ-Al2O3 and Pt facilitates the hydrogenation. In the current work, effect of both; solid base and Sn as a promoter has been studied to improve the yields of sugar alcohols from various C5 and C6 sugars at very mild reaction conditions.

10aBimetallic catalyst10aHydrogenation10aHydrotalcites10aSugar10aSugar alcohols1 aTathod, Anup, P.1 aDhepe, Paresh, L. uhttps://library.ncl.res.in/content/elucidating-effect-solid-base-hydrogenation-c5-and-c6-sugars-over-pt%E2%80%93sn-bimetallic-catalyst02620nas a2200253 4500008004100000022001400041245009600055210006900151260000800220300001100228490000800239520172800247653002801975653002202003653001902025653002202044653003302066653004802099100002202147700002202169700002202191700002902213856012402242 2025 eng d a0019-452200aExperimental investigation and lumped kinetic modeling studies for upcycling of polyolefins0 aExperimental investigation and lumped kinetic modeling studies f cNOV a1021270 v1023 a

The present work discusses on comparative kinetic analysis of the pyrolysis of polypropylene (PP), high-density polyethylene (HDPE), and low-density polyethylene (LDPE) using sophisticated lumped models. Unlike many previous studies that focused on single-polymer kinetic models or employed simplified reaction schemes, this study develops an enhanced multistep reaction network that explicitly considers both primary decomposition and secondary cracking pathways, thereby improving the accuracy of product distribution predictions. By integrating this detailed reaction framework with a robust nonlinear regression approach using LSQNONLIN and ODE45 solvers in MATLAB, the study achieved greater accuracy in estimating kinetic parameters than traditional curve-fitting methods. The findings reveal that HDPE exhibits the highest activation energy (222.97 kJ mol(-1)), indicating it is more thermally stable than LDPE (193.44 kJ mol(-1)) and PP (62.16 kJ mol(-1)). One of the highlights of the present work is that lower pyrolysis temperature (400 degrees C) is found to be optimum for liquid yield by reducing secondary cracking, which aligns with the sustainable fuel production principles. The study also emphasizes on the limitations of previous lumped models that overlooked wax decomposition pathways, which are crucial for optimizing the hydrocarbon distribution. Future research should investigate catalytic interventions and reactor design modifications to enhance the product selectivity and scalability. This study offers a more comprehensive kinetic framework for advancing the valorization of plastic waste through pyrolysis, aiding the development of efficient waste-to-fuel conversion strategies.

10aLumped kinetic modeling10aPlastic pyrolysis10aRate constants10aReaction pathways10aSecondary cracking reactions10aTemperature-dependent product distributions1 aKavade, Omkar, G.1 aDhepe, Paresh, L.1 aDevi, Nandini, R.1 aVasireddy, Satyam, Naidu uhttps://library.ncl.res.in/content/experimental-investigation-and-lumped-kinetic-modeling-studies-upcycling-polyolefins