Synthesis of methyl acetate by nano-photocatalyst based on titania: Temperature dependence studies

Abstract

Design of low energy processes for synthesis of industrially important esters is imperative expanse of research. Sulphonated Titania based nano-catalysts have been prepared by wet impregnation route has been utilizated for low energy photo-catalytic synthesis of methyl acetate at ambient temperature conditions and optimized the parameters for maximum conversion. In the present paper we have carried out the kinetic study of the reaction at optimized conditions of catalyst loading and molar ratio varying the thermal conditions to observe the effect of temperature on the reaction conversion and equilibrium time. Morphology of the catalysts was analysed using Scanning electron microscopy which suggest a stable and oval particle morphology of the catalyst particles. Sulphonation characteristics of the catalyst was characterized by FT-IR analysis in bare as well as activated state. The kinetic data has been modelled according to second order kinetic model to calculate forward rate constant at various temperatures and maximum reaction rate of 6.77 E-05 L 2 g − 1 mol -1 min −1 was observed at 333.15 K. Further activation energy of the reaction has been calculated by Arrhenius equation and Activation energy for the overall process was 22.26 kJ/mol. The reaction enthalpy calculated from Vant Hoff equation was found to be 47.66 kJ/mol and entropy was found to be 142.03 J/mol/K. Therefore this photocatlytic material can efficiently catalyze the esterification reaction of acetic acid and methanol at low energy conditions. This finding has broaden and deepen fundamental understanding of CH 3 C O O H on TiO 2 surface and demonstrate a low energy route for esterification reactions.