Direct synthesis of dimethyl carbonate from CO2 and methanol over ZIF-67/CeO2

An efficient heterogeneous catalyst ZIF-67/CeO2 composites were synthesized by a precipitation method, and developed for the direct synthesis of dimethyl carbonate (DMC) from CO2 and methanol. The physicochemical properties of the ZIF- 67/CeO2 catalysts were investigated by X-ray diffraction, N-2 adsorption-desorption, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The results demonstrated that the introduction of ZIF-67 causes more oxygen vacancies to be generated onto CeO2. Among the ZIF-67/CeO2 catalysts, 0.3-ZIF- 67/CeO2 (0.3 was the molar ratio of Co and Ce) showed the best catalytic performance due to its high specific surface area, mesoporous structure, and high CO2 adsorption capacity. Yield of 3.79 mmol(DMC)center dot g(cat)(-1) was achieved at a temperature of 140 degrees C and a pressure of 4.5 MPa for 4 h.