Electrochemical activation of carbon dioxide for synthesis of dimethyl carbonate in an ionic liquid

Abstract

The direct synthesis of dimethyl carbonate from methanol and carbon dioxide is challenging due to the thermodynamic stability and kinetic inertness of CO 2. Electrochemical technique can overcome this challenge by providing a method for preliminary activation of CO 2. Electrocatalytic activation and conversion of carbon dioxide to dimethyl carbonate with platinum electrodes in a dialkylimidazolium ionic liquids–basic compounds–methanol system was conducted under ambient conditions. Among the basic compounds and ionic liquids, CH 3OK acts as a co-catalyst and 1-butyl-3-methylimidazolium bromide (bmimBr) acts as an electrolyte. In the bmimBr–CH 3OK–methanol system, the absence of CH 3I and/or any other organic additives allows dimethyl carbonate to be effectively synthesized. The reaction mechanism proposed here is different from those previously reported.