文献类型：期刊文献

英文题名：Comparative Studies of Phosphate-Modified CeO2 and Al2O3 for Mechanistic Understanding of Dichloromethane Oxidation and Chloromethane Formation

作者：Zhang, Long[1,2];Deng, Wei[1,2];Cai, Yuanpu[2];Dai, Qiguang[2];Guo, Limin[1]

机构：[1]Huazhong Univ Sci & Technol, Sch Environm Sci & Technol, Wuhan 430074, Peoples R China;[2]East China Univ Sci & Technol, Res Inst Ind Catalysis, Key Lab Adv Mat, Sch Chem & Mol Engn, Shanghai 200237, Peoples R China

年份：2020

卷号：10

期号：21

起止页码：13109

外文期刊名：ACS CATALYSIS

收录：;EI(收录号：20204609488942);WOS:【SCI-EXPANDED(收录号:WOS:000589939900067)】；

基金：This work was sponsored by the National Key Research and Development Program of China (2017YFE0127400), the Natural Science Foundation of Shanghai (19ZR1412900), the Natural Science Foundation of Hubei Province (2019CFA070), and the Program for Huazhong University of Science and Technology (HUST) Academic Frontier Youth Team (2018QYTD03). The authors thank the Analysis and Testing Center of Huazhong University of Science and Technology for analytical support.

语种：英文

外文关键词：catalytic combustion; CVOCs; Ceria; acid-base; hydrodechlorinated

摘要：A phosphate-modified CeO2 nanosheet as a promising catalyst presenting high activity, durability, and selectivity for catalytic oxidation of chlorinated volatile organic compounds (CVOCs) was used to investigate mechanisms of dichloromethane (DCM) oxidation and monochloromethane (MCM) formation by comparison with Al2O3-based catalysts, and CeO2-based catalysts showed a higher activity for DCM oxidation and lower selectivity for MCM. A series of well-designed experiments including various isotopic experiments revealed that an acid-base pair catalysis was involved, that is, DCM mainly dissociated on Lewis acid sites and then dehydrochlorinated through hydroxyl groups/Bronsted acid sites, while the basicity was intrinsic to the generation of MCM via a hydride transfer reaction between DCM activated on basic sites and DCM dissociated on Lewis acid sites. Moreover, the superior redox ability could suppress the formation of MCM by a rapid catalytic oxidation but prompt the possible formation of Cl-2 and polychlorinated byproducts.