Effect of high temperature pretreatment on the thermal resistance properties of Pd/CeO2/Al2O3 close-coupled catalysts
来源期刊:JOURNAL OF RARE EARTHS2017年第2期
论文作者:黄木兰 王苏宁 兰丽 张海龙 史忠华 陈耀强
文章页码:149 - 157
摘 要:Fresh Pd/CeO2/Al2O3 close coupled catalyst was prepared by the stepwise impregnation method and calcined at 550 °C for 3 h, which was then pretreated at 700, 800, and 900 °C for 3 h, respectively. Finally, these pretreated catalysts were aged at 1000 °C for 3 h to study their anti-aging properties. The catalytic activities of the catalysts were investigated detailedly, and the results showed that the catalyst pretreated at 800 °C before aging treatment possessed the best anti-aging performance for C3H8 oxidation. XRD and XPS results indicated that well-crystallized CeO2 particles were formed during calcinations at 800 °C, which made CeO2 an effective promoter. HRTEM revealed that Pd particles found on the edge of CeO2 over the aged catalyst pretreated at 800 °C were relatively smaller than those over the catalysts without pretreatment. H2-TPR and XPS results also implied that the interaction between well-crystallized CeO2 and Pd suppressed the deactivation of PdO sites and further enhanced the catalytic performance.
黄木兰1,王苏宁2,兰丽1,张海龙2,史忠华1,3,4,陈耀强1,3,4
1. Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry,Sichuan University2. College of Chemical Engineering, Sichuan University
摘 要:Fresh Pd/CeO2/Al2O3 close coupled catalyst was prepared by the stepwise impregnation method and calcined at 550 °C for 3 h, which was then pretreated at 700, 800, and 900 °C for 3 h, respectively. Finally, these pretreated catalysts were aged at 1000 °C for 3 h to study their anti-aging properties. The catalytic activities of the catalysts were investigated detailedly, and the results showed that the catalyst pretreated at 800 °C before aging treatment possessed the best anti-aging performance for C3H8 oxidation. XRD and XPS results indicated that well-crystallized CeO2 particles were formed during calcinations at 800 °C, which made CeO2 an effective promoter. HRTEM revealed that Pd particles found on the edge of CeO2 over the aged catalyst pretreated at 800 °C were relatively smaller than those over the catalysts without pretreatment. H2-TPR and XPS results also implied that the interaction between well-crystallized CeO2 and Pd suppressed the deactivation of PdO sites and further enhanced the catalytic performance.
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