A series of Pd catalysts supported on commercial Ce-Zr solid solution（Pd/CZ） calcined at different tem- peratures（750, 900 and 1050 %℃） was prepared via an incipient wetness impregnation method. The activities of...A series of Pd catalysts supported on commercial Ce-Zr solid solution（Pd/CZ） calcined at different tem- peratures（750, 900 and 1050 %℃） was prepared via an incipient wetness impregnation method. The activities of the fresh and hydrothermally aged PdTCZ catalysts were tested for total oxidation of CO and C3H8. For CO oxidation, the activity of either fresh or aged Pd/CZ catalysts decreased with the elevating of calcination temperature of CZ support, with a fresh catalyst calcined at 750 ℃ possessing the highest activity and hydrothermal stability. For C3H8 total oxidation, the activity of Pd/CZ catalysts could be improved by increasing the calcination temperature of support. However, the aged Pd/CZ catalysts showed higher activity than corresponding fresh Pd/CZ catalysts. The turnover frequency（TOF） over Pd/CZ catalyst for CO oxidation increased with increasing reduction ability of the catalysts, with a fresh catalyst calcined at 750 ℃ having the highest value（0.27 s^-1）. However, the TOF of Pd/CZ catalyst for C3Hs total oxidation was mainly affected by the size of Pd particles, and large Pd particles possessed a higher activity, with the highest TOF value（0.96s^-1） obtained over an aged catalyst calcined at 1050 ℃.展开更多
文摘A series of Pd catalysts supported on commercial Ce-Zr solid solution（Pd/CZ） calcined at different tem- peratures（750, 900 and 1050 %℃） was prepared via an incipient wetness impregnation method. The activities of the fresh and hydrothermally aged PdTCZ catalysts were tested for total oxidation of CO and C3H8. For CO oxidation, the activity of either fresh or aged Pd/CZ catalysts decreased with the elevating of calcination temperature of CZ support, with a fresh catalyst calcined at 750 ℃ possessing the highest activity and hydrothermal stability. For C3H8 total oxidation, the activity of Pd/CZ catalysts could be improved by increasing the calcination temperature of support. However, the aged Pd/CZ catalysts showed higher activity than corresponding fresh Pd/CZ catalysts. The turnover frequency（TOF） over Pd/CZ catalyst for CO oxidation increased with increasing reduction ability of the catalysts, with a fresh catalyst calcined at 750 ℃ having the highest value（0.27 s^-1）. However, the TOF of Pd/CZ catalyst for C3Hs total oxidation was mainly affected by the size of Pd particles, and large Pd particles possessed a higher activity, with the highest TOF value（0.96s^-1） obtained over an aged catalyst calcined at 1050 ℃.
