Efficient hydrogenation of CO2-derived ethylene carbonate to methanol and ethylene glycol over Mo-doped Cu/SiO2 catalyst

Abstract Hydrogenation of ethylene carbonate (EC) to methanol and ethylene glycol is an attractive method for indirect hydrogenation of CO2 to methanol. Copper-based catalysts have been studied in EC hydrogenation because of their good selective activation ability for carbon-oxygen bonds. Herein, a series of Mo-doped Cu/SiO2 catalysts were prepared and used for EC hydrogenation. The catalyst with 0.5 wt% Mo dopant exhibited the highest catalytic performance of 80.9 % MeOH yield and 98.6 % EG yield with an excellent stability for at least 140 h. Detailed characterizations revealed that a proper amount of Mo addition could be beneficial to enhancing the copper dispersion and preventing them from aggregation. Moreover, it is demonstrated that the amount of surface Cu+ species was increased with some electron-deficient ones generated resulting from the strong interaction between copper and molybdenum species, which may effectively promote the activation of EC. The optimal 0.5 wt% Mo-doped catalyst showed remarkably enhanced efficiency and the apparent activation energy barrier of 115.8 kJ mol−1 is much lower than that of the Mo-free sample in EC hydrogenation. The insights may bring new possibilities to further design efficient copper-based catalysts for the hydrogenation of carbon-oxygen bonds.