Zeolite catalysts for the water gas shift reaction

Abstract

Cu- and Cu,Zn-ZSM-5 zeolite catalysts were prepared using different cation exchange procedures. The samples were characterized by TPR; CO-FTIR; O2-TPD, XRD; BET and XPS. These catalysts showed appreciable activity and selectivity for the water gas shift reaction at 300–400°C and vapor/gas ratio=3. The Cu,Zn-ZSM-5 catalysts deactivated after a long exposure to steam, at high temperature. The catalytic activity of co-exchanged zeolite catalysts depended on the preparation method. The introduction of zinc ions enhanced the activity of the Cu-ZSM-5 catalysts but Zn-ZSM-5 catalyst was found to be inactive for the water gas shift reaction. The role of zinc was to change the distribution of the copper species in the zeolite catalyst.