Mono lacunary silicotungstate anchored to nano-porous MCM-48: synthesis, characterization and esterification of bioplatform molecules to fuel additives

An emerging research field of the development of polyoxometalate based catalysts has evoked tremendous revolution in biomass conversion. The present work deals with the synthesis of one such new catalyst comprising of mono lacunary silicotungstate (SiW11) and silicious nano-porous support, nMCM-48. The catalyst has been characterized in detail by several physicochemical techniques and its activity was evaluated for catalytic esterification of two top most selected bioplatform molecules (levulinic acid and succinic acid) for the synthesis of fuel additives. A detailed optimization study of both reactions has been carried out and appreciable conversions, 49 % and 83 % of levulinic acid and succinic acid were achieved with TOF of 325 and 183 h−1, respectively. The activation energy for both reactions was determined and the recycling studies were carried out to establish its sustainable nature. Moreover, the feasibility aspect of the catalyst was studied by comparing the activity of both levulinic and succinic acid in identical reaction conditions.