Comparative Study on the Effect of Cerina and Alumina on the Catalytic Activity of CuO-ZnO Based Catalyst in CO2 Hydrogenation to Methanol

Ternary Cu/ZnO/Al 2 O 3 and Cu/ZnO/CeO 2 catalysts were prepared by polyol method and tested for gas-phase low-temperature methanol synthesis from hydrogenation of CO 2 . The catalysts were characterized by N 2 physisorption, SEM–EDX, XRD, H 2 -TPR and XPS. The activity of the catalysts was evaluated in a fixed-bed micro-reactor at atmospheric pressure and 40 bar at different reaction temperatures, and H 2 /CO 2 ratio of 3:1. The results showed that the nature of the promoter influenced the physicochemical properties of the catalysts as well as the catalytic activity and product selectivity. Compared with ternary Cu/ZnO/Al 2 O 3 catalyst, Cu/ZnO/CeO 2 catalyst indicated that modifcation of CuO/ZnO catalyst with CeO 2 promoted the CuO dispersion, reduced the CuO crystallite size, decreased the reduction temperature of highly dispersed CuO, decreased the activation energy and improved the catalytic activity of the Cu/ZnO/CeO 2 catalyst. Graphical Abstract