Propene oxidation over palladium catalysts supported on zirconium rich ceria-zirconia

Ceria-zirconia solid solution with the Ce/Zr ratio of 1/3 was prepared and used as support material for palladium catalysts. The palladium catalysts supported on the zirconium rich ceria-zirconia (Pd/CZ) were studied for propene oxidation reaction. In the activity tests, the influences of palladium loadings, pretreatment conditions, and reaction conditions were investigated. The catalytic activities of Pd/CZ with small amount of palladium component were strongly affected by the pretreatment conditions such as oxidative or reductive atmosphere. From IR measurements, it was suggested that the palladium species with high reducibility should be active for the complete oxidation of propene. The initial activities of Pd/CZ catalysts under the insufficient oxygen condition were equivalent to the activities under the stoichiometric condition due to the property of high oxygen storage capacity (OSC). It was revealed that CZ support helped the high dispersion of palladium oxide particles and its OSC property assisted the propene oxidation reaction. (C) 2014 Elsevier By. All rights reserved.