Evolution of active sites and catalytic consequences of mesoporous MCM-41 supported copper catalysts for the hydrogenation of ethylene carbonate

Abstract

Understanding the nature of copper active sites and structural evolution in preparation is crucial to rational design of copper catalysts for ethylene carbonate hydrogenation. The Cu/MCM-41 catalysts were prepared to focus on the evolution of Cu species by varying the Cu/Si mass ratio in the deposition-precipitation process. The synthesis mechanism, physicochemical properties as well as quantitative Cu active species over Cu/MCM-41 catalysts were systematically characterized and the catalytic performance was evaluated to get insight into structure–activity relationship for the ethylene carbonate (EC) hydrogenation. The results indicated that the Cu/Si ratio significantly influenced the formation of Cu0 and Cu+ active sites over the catalysts, which are derived from the CuO and Cu silicates, respectively. The appropriate textural structures, high surface Cu dispersion and synergetic effect between Cu0 and Cu+ sites of the 0.7Cu/MCM-41 catalyst resulted in an outstanding performance for EC hydrogenation, with turnover number (TON) of 18.63 and 13.82 to ethylene glycol and methanol.