Abstract:
The catalytic performance of Pd/CeO2, Pd/ZrO2, and Pd/CeO2-ZrO2 catalysts in selective CO oxidation in the presence of large amounts of hydrogen were investigated for fuel cell applications. Co-precipitation and impregnation on supports prepared by sol-gel methods were used to prepare the catalysts. The results from XRD and BET revealed that the sol-gel catalysts had high crystallinity and surface area especially for Pd on mixed oxide supports. The calcination temperature, ratio of Pd to Ce and Zr loading, and catalyst preparation method had strong effect on catalyst activity. The catalysts prepared by co-precipitation method had higher activity than catalysts prepared by impregnation method. The l%Pd/CeO2 co-precipitation catalyst calcined at 300℃ for two hours exhibited the highest activity. Pretreatment of the catalyst by reducing with 10% H2 at 300℃ for three hours maximized the activity.