Electrosynthesis of dimethyl carbonate from methanol and CO2 using potassium methoxide and the ionic liquid [bmim][Br] in a filter-press cell: A study of the influence of cell configuration

Abstract

BACKGROUND: The valorization of CO2 into added-value products appears to be a promising strategy for reducing CO2 emissions. Dimethyl carbonate (DMC) is an environmentally friendly valuable product, with multiple applications, suggested as a potential gasoline additive. However, DMC has traditionally been produced from hazardous phosgene and CO routes, which encourages the interest in developing new processes. The purpose of this work is to study the influence of the membrane in a filter-press electrochemical cell for the valorization of CO2 by the electrosynthesis of DMC from methanol in the presence of the ionic liquid [bmim][Br] and CH3OK and avoiding the addition of carcinogens. RESULTS: The performance of the process has been studied using six different anion exchange membranes in comparison with an undivided configuration and our previous study using a cationic exchange membrane. A significant increase in the initial reaction rate is achieved when no membrane is employed. Regardless of which membrane is used, an additional resistance seems to be introduced. A final concentration of 85mmolL-1 was obtained up to 48h without membrane, which is a 6-fold increase over our previous work. CONCLUSIONS: Although better results were obtained when no membrane was used, study of the divided cell has provided experimental evidence that can serve as a reference for the evaluation of future improvements in this electrosynthesis.