燃料化学学报2017，Vol.45Issue(5)：572-580,9.
焙烧气氛对二甲醚低温选择氧化MoO3-SnO2催化剂结构及性能的影响
Effects of calcination atmosphere on the structure and performance of MoO3-SnO2 catalyst for the oxidation of dimethyl ether at low temperature
摘要
Abstract
MoO3-SnO2 catalysts with a Mo/Sn molar ratio of 1:3 was prepared by the co-precipitation method and calcined in different atmospheres (O2,air,N2 and H2);the effect of calcination atmosphere on the catalytic performance of MoO3-SnO2 in the oxidation of dimethyl ether (DME) to methyl formate (MF) was investigated.The results show that the MoO3-SnO2 catalyst prepared by calcination in O2 exhibits the highest activity;the conversion of DME reaches 25.10%,with the selectivity of 72.21% to MF.Over the catalyst calcined in H2,the conversion of DME is only 7.01%,with the selectivity of 75.82% to MF.The activity of the MoO3-SnO2 catalysts calcined at different atmospheres follows the order of O2 > air > N2 > H2.The results of XRD,Raman,XPS and ESR characterization indicate the presence of MoOx domains on the surface of the MoO3-SnO2 catalyst with a Mo/Sn molar ratio of 1:3.The terminal Mo=O groups of oligomeric MoO3 may be the active sites for the methoxy intermediate and the penta-coordinated Mo5+ species in the Mo-Sn interface may be able to promote the oxidation of DME to MF.Consequently,methoxy species are absorbed on the Mo5+ species in the Mo-Sn interfaces,which are oxidized to HCHO on the terminal Mo=O groups;after that,the absorbed HCHO may then react with the neighboring absorbed methoxy species,forming MF.关键词
MoO3-SnO2催化剂/焙烧气氛/二甲醚氧化/甲酸甲酯Key words
MoO3-SnO2 catalysts/calcination atmosphere/dimethyl ether oxidation/methyl formate分类
化学化工引用本文复制引用
顾颖颖,张振洲,王文峰,高秀娟,张清德,韩怡卓,谭猗生..焙烧气氛对二甲醚低温选择氧化MoO3-SnO2催化剂结构及性能的影响[J].燃料化学学报,2017,45(5):572-580,9.基金项目
The project was supported by the National Natural Science Foundation of China (21373253,20903114) and Youth Innovation Promotion Association CAS (2014155).国家自然科学基金(21373253,20903114)和中国科学院青年创新促进会(2014155)资助 （21373253,20903114）
