Effect of calcination temperature on catalytic performance of CuCe/AC catalysts for oxidative carbonylation of methanol

The CuCe/AC catalysts were prepared by impregnation first with Ce and then with Cu, and effect of calcination temperature on catalytic performance of the CuCe/AC catalysts for gas-phase oxidative carbonylation of methanol to dimethyl carbonate was studied. The active component content and valence state of as-prepared catalysts were characterized by XRD, XPS and H2-TPR. The results show that Cu2+ is gradually reduced to Cu+ and Cu0 species. After calcinated at 450°C, some Cu2O phase still exists in the catalyst, which indicates that interaction between Cu and Ce has suppressed the reduction of Cu2O. As the calcination temperature of 300°C, the content of Cu+ achieves the highest, and the corresponding catalyst shows the best catalytic activity. The space-time yield of DMC, selectivity of DMC and conversion of methanol are 143.4 mg/(g·h), 85.2% and 4.1%, respectively.