Influence of the support composition on the hydrogenation of methyl acetate over Cu/MgO-SiO2 catalysts

Abstract

A series of Cu/MgO-SiO2 catalysts with different support compositions of MgO and SiO2 were prepared using the ammonia-evaporation method and evaluated for methyl acetate hydrogenation reaction to synthesize ethanol. Physicochemical properties of these catalysts were investigated by N2 physisorption, N2O chemisorptions, X-ray diffraction, H2-temperature programmed reduction, CO2-temperature programmed desorption and X-ray photoelectron spectroscopy. It was found that the MgO content significantly influenced the chemical properties, then affected catalytic activities of Cu/xMgO-SiO2 catalysts. The optimal catalytic performance was obtained over Cu/9MgO-SiO2 catalyst with MgO/SiO2 mass ratio of 9 with the methyl acetate conversion of 80.3% and ethanol selectivity of 99.0%. The high catalytic performance of Cu/9MgO-SiO2 catalyst was attributed to the fine copper dispersion and large amount of weakly basic sites and Cu+ species.