Increasing energy requirements and environmental pollution, along with predicted shortages of fossil fuels in the near future, have accelerated the search for alternative renewable energy sources. Biomass is a promising renewable resource for the production of value-added fuels and chemicals. In this work, triglycerides, furfural and 5-hydroxymethylfurfural (HMF) are used as bio-derived feedstock chemicals for chemo- or electro-catalytic conversion to valuable chemicals that find applications in fuels, polymer, perfumery and pharmaceutical industries.Chemical interesterification of triglycerides was conducted with methyl acetate, as an alternative to transesterification, to co-produce biodiesel and a higher value-added compound, triacetin, instead of glycerol. Conversion of waste methyl acetate in terephthalic acid production industry using triglyceride into two valorized products biodiesel and triacetin is a novel idea. Biodiesel is a well-known renewable fuel and triacetin can be used as a fuel additive. Amongst various base catalysts screened, calcined Mg-Al hydrotalcite (Mg:Al mole ratio - 3:1) was found to have the best activity in terms triglyceride conversion and triacetin selectivity.We also studied the etherification of HMF with ethylene glycol to produce 5-(2- hydroxyethoxymethyl) furfural (HEMF), which finds application as a fuel additive. Metal substituted heteropoly acid catalysts were identified as a chemo-selective catalyst that favored etherification of HMF over acetalization reaction. Aluminum substituted dodecatungsto-phosphoric acid achieved the highest HMF conversion and HEMF selectivity, which was attributed to the combined role of the catalyst's Lewis and Bronsted acidity.Further, electrocatalytic hydrogenation (ECH) of furfural using zinc as a novel metal catalyst was studied to produce furfuryl alcohol and 2-methylfuran, which have applications in pharmaceutical, polymer and fuel industries. The effect of metal catalyst and electrolyte pH on the yield and Faradaic efficiency (FE) of the desired products was studied. Electrolysis at neutral pH (pH 6 to 8) exhibited increased yields and FE as compared to acidic and basic pH. FE for ECH of furfural with Zn was remarkably higher as compared to Cu and Ni.However, during ECH of furfural, the total yield of the desired products was low compared to the conversion of furfural which was due to electrodimerization reactions. Thus, zinc metal nanoparticles were synthesized by electrodeposition to achieve higher activity for furfural ECH as compared to bare zinc metal due to high surface area and roughness. Furfural electrolysis in 0.5 M bicarbonate electrolyte at -0.6 V/RHE yielded higher conversion, yield and FE as compared to bare zinc. Catalyst characterization revealed the presence of surface zinc oxide species post- electrolysis, which could have a role in reaction mechanism.Overall, this work contributes to the field of biomass valorization, by identifying new selective catalysts and processes to produce value-added chemicals using renewable bio-derived feedstocks. Catalyst synthesis, reaction engineering and process optimization studied for biomass conversion processes in this work will aid in future process intensification of such processes.
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