Conversion of biomass into valuable chemicals is highly sought after across the globe. 5-Hydroxymethyl furfural (HMF) is a biobased platform chemical which could be valorized into a spectrum of fuels and chemicals. In the current work, HMF was transformed into 2,5dimethyl furan (2,5-DMF) using a number of catalysts amongst which a novel bifunctional metal-acid catalyst, Pd-Cs 2.5 H 0.5 PW 12 O 40 /K-10 clay, palladium-cesium dodecatungstophosphoric acid supported on K-10 acidic clay, was found to be the best. Because of its high energy density, 2,5-DMF is a potential biofuel additive. The acidic nature of Cs-DTP/K-10 facilitates rapid hydrogenolysis of HMF at mild reaction condition. 2% Pd-20 % w/w CsDTP/K-10 clay designated as 2Pd-20CsDTP/K-10 gives 98% conversion of HMF with 81% selectivity to 2, 5-DMF at 90 o C and 10 atm hydrogen pressure in 2 h. The catalyst was prepared by a simple and cheap wet impregnation method and characterized, both before and after reuse, by XRD, FTIR, BET surface area, NH 3 -TPD, TGA, TEM and SEM. The catalyst was robust and could be used with very minimal loss in activity. The reaction mechanism and kinetics are also presented. The overall process is clean, green and sustainable.

Magnetically separable sulfated zirconia catalysts were prepared by a two-step approach.

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A series of (20% w/w) aluminium exchanged dodeca-tungstophosphoric acids (DTP) (Alx-DTP, x = 0.33–1) supported on montmorillonite K-10 clay were synthesized and completely characterized by sophisticated techniques and used in benzoylation of diphenyl oxide.

Glycerol esterification with acetic acid produces a mixture of mono, di, and triacetins, which are commercially important value-added products with a wide range of industrial uses including their application as fuel-additives, thus contributing to environmental sustainability and economic viability of the biorefinery concept. Glycerol esterification with acetic acid was studied using a range of nitrogen-based Brønsted-acidic ionic liquids. Cost-effective and easily synthesized Brønsted-acidic ionic liquids based on alkyl-pyrrolidone and alkyl-amine cations were synthesized and characterized using 1H NMR spectroscopy. The catalytic activity of the Brønsted-acidic ionic liquids produced were investigated for the production of di and triacetin from glycerol and acetic acid. Amongst all ionic liquids evaluated in this study, N-methyl-2-pyrrolidinium hydrogen sulfate [H-NMP]­[HSO4] was found to be the most active and cost-effective catalyst. The effect of significant reaction parameters on selectivity to the trisubstituted product, triacetin, was modeled using a design of experiment (DoE) approach with a response surface methodology involving a central composite design. The esterification process was optimized to maximize the production of triacetin. Optimizing the process this way naturally leads to lower levels of mono and diacetin. Amongst the reaction parameters evaluated, temperature had the greatest influence on product selectivity, followed by the glycerol to acetic acid molar ratio, and the model also showed dependence on the synergistic interaction between the temperature and mole ratio. It is worth noting that agitation speed had minimal influence on product selectivity. Under optimized reaction conditions, >99% glycerol conversion was achieved with 42.3% selectivity to triacetin, and a combined di and triacetin selectivity of >95% within 1 h.

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To decrease the dependence on crude oil, biomass derived liquid transportation fuels are highly desirable. Butyl levulinate is potential cellulose-derived biofuel additive with properties similar to diesel and low water solubility. Herein we report direct one-pot production of levulinic acid ester, butyl levulinate from furfuryl alcohol by alcoholysis using n-butanol.The partial tin exchanged tungstophosphoric acid (TPA) supported on montmorillonite K-10 catalysts showed facile alcoholysis of furfuryl alcohol to levulinate ester under mild temperature conditions. Partially, exchanging the H + ion of TPA with Sn (x = 1) resulted in enhanced acidity of the catalyst and showed an increase in the catalytic activity as compared to TPA/K-10 catalyst. A series of tin exchanged tungstophosphoric acid (20% w/w) supported on montmorillonite K-10 clay (Snx-TPA/K-10, where x = 0.5-1.5) were synthesized and thoroughly characterized by using XRD, FT-IR, UV-VIS, titration and SEM techniques. Among various catalysts, Sn1-TPA/K-10 was found to be the most active catalyst for butyl levulinate synthesis. Two different clay supports and varying tin loadings were used to study the effects on surface acidity as well as catalytic activity in butyl levulinate synthesis. Effects of different reaction parameters were studied and optimized to get high yields of butyl levulinate. Under mild reaction conditions at 110°C, complete conversion of furfuryl alcohol with 98% selectivity to butyl levulinate was achieved. The prepared catalyst could be recycled at least five times without significant loss of activity. The overall process is green and clean.