Selective Hydrogenation of Carbon Dioxide to Methanol on Cu-ZnO/SiO2 Catalysts Prepared by Alkoxide Method

Article abstract of DOI:10.1246/bcsj.65.2520

Hydrogenation of CO2 to methanol was carried out on Cu-ZnO/SiO2 catalysts at 493 K and 3 MPa with a flow rate of 100 cm³min^-1 (H2/CO2=2).Higher selectivity (>90percent) was observed on the catalysts prepared by the alkoxide method than on a conventional catalyst prepared by the impregnation method.The selectivity was higher on the catalysts pretreated with H2 at a higher temperature, except at 873 K.The activity of the catalyst pretreated at 873 K was extremely low, probably because of alloy formation.The results of XRD, XPS, and EXAFS demonstrate that the active species for methanol formation is a large metallic Cu particle covered with a partially oxidized layer interacting with highly dispersed ZnO.