Morphology effect of cerium dioxide on the catalytic performance of Ru/CeO2 catalyst for the oxidation of different CVOCs
Baocheng Xie, Zhuopeng Wang, Xin Zhang, Min Ding, Mingqi Li, Xiaohan Guo, Qiguang Dai, Li Wang, Wangcheng Zhan, Yun Guo, Yun Guo, Aiyong Wang, Yanglong Guo, Yanglong Guo
Abstract
CeO 2 with different morphology of rod-shape (R-CeO 2 ), cube-shape (C-CeO 2 ) and octahedra-shape (O-CeO 2 ) were synthesized as supports and impregnated with Ru to obtain Ru/CeO 2 catalysts, and the performance of which in catalytic oxidation of different chlorine-containing volatile organic compounds (CVOCs) (1,2-dichloroethylene (DCE) and vinyl chloride (VC)) were investigated. Due to the stronger interaction between Ru and R-CeO 2 , Ru was highly dispersed on R-CeO 2 and more Ru entered support lattice to form Ru-O-Ce structure, thus Ru/R-CeO 2 catalyst exhibited better redox property. Ru addition enhanced the acidity of Ru/R-CeO 2 and Ru/C-CeO 2 , while that of Ru/O-CeO 2 decreased instead. The acidity mainly affected DCE catalytic activity when catalyst had sufficient redox property and chlorine resistance. Ru n+ content was the main factor affecting VC catalytic activity. Ru/R-CeO 2 catalyst exhibited the best catalytic activity in both DCE and VC catalytic oxidation with T 50 of 285 °C and 207 °C, respectively, due to its excellent redox property, acidity, and sufficient Ru n+ . In situ DRIFTS suggested that DCE was first dissociated to VC and then oxidized to carboxylates, and the addition of Ru led to the oxidation of carboxylates to carbonyl and ultimately to complete oxidation to CO 2 and H 2 O. Ru n+ was important for the oxidation of carboxylate intermediates.