Significant influence of microwave dielectric heating on ionic liquid catalyzed transesterification of ethylene carbonate with methanol

This paper reports an energy efficient route for the transesterification of ethylene carbonate (EC) with methanol using ionic liquid (IL) as catalyst through microwave heating. The influence of the reaction parameters such as the microwave irradiation time, power, EC/methanol ratio, and the cation and anion of both 1-alkyl-3-methyl imidazolium and tetraalkyl ammonium salts, was examined under these conditions. Also the heating characteristics of this reaction mixture were examined at various intervals. The coproduction of an equimolar amount of dimethyl carbonate (DMC) and ethylene glycol (EG) were obtained in high yield and better selectivity. Comparative studies were carried out under different reaction conditions with classical heating modes. An induction period observed during conventional reaction can be avoided by microwave dielectric heating. Overall, this study highlights an environmentally benign technology for the production of DMC, a “green reagent”, through microwave irradiation.

The efficiency of microwave heating over conventional transesterification reaction and the heating characteristics of transesterification reaction mixture in the presence of ionic liquids were investigated. The microwave specific heating provided a rapid and sustainable approach for transesterification of ethylene carbonate with methanol.Figure optionsDownload as PowerPoint slide