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

The direct synthesis of dimethyl carbonate from methanol and carbon dioxide is challenging due to the thermodynamic stability and kinetic inertness of CO2. Electrochemical technique can overcome this challenge by providing a method for preliminary activation of CO2. 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, CH3OK acts as a co-catalyst and 1-butyl-3-methylimidazolium bromide (bmimBr) acts as an electrolyte. In the bmimBr-CH3OK-methanol system. the absence of CH3I and/or any other organic additives allows dimethyl carbonate to be effectively synthesized. The reaction mechanism proposed here is different from those previously reported. (C) 2008 Elsevier Ltd. All rights reserved.