Electrocatalytic Synthesis of Propylene Carbonate from CO_2 and Propylene Oxide

The electrocatalytic synthesis of propylene carbonate(PC) from CO2 and propylene oxide(PO) was studied under mild conditions(PCO2=1.01×105 Pa, t=25 ℃). Influences of solvents, supporting electrolytes, the passed charge, the nature of electrodes and the current density(j) on the yield of PC were investigated to optimize the electrolytic conditions, with the maximal yield to be 46.2%, the selectivity of propylene carbonate is 100%. The reduction of propylene oxide in the absence and presence of CO2 was examined by cyclic voltammetry. The mechanism of the reaction initiated by the synergistic effect of halides ions of supporting electrolytes with nucleophilicity and the metal ions from scarification anode with Lewis acid acidity was proposed on the basis of our results.