摘要
制备了用于正己烷临氢异构化的氧化硅担载的Keggin型杂多酸和还原态Pt-Ce氧化物催化剂.这些混合氧化物催化剂或单独使用,或与氧化硅担载的杂多酸催化剂一起使用.用X射线衍射、傅里叶变换红外光谱、傅里叶变换拉曼光谱、热重和N2物理吸附等方法表征在氧化、还原态和催化实验后的催化剂状态.本文的目的是在最佳反应条件(反应温度、还原温度和流量等)下,筛选出具有最好异构化收率的催化剂.结果表明,还原氧化物的存在不但有利于消除积炭,而且在反应期间能有效地维持氧化硅担载杂多酸的结构.从这些催化剂样品中,可以找到具有更好异构化活性和选择性的催化剂.
Catalysts based on Keggin-type heteropolyacids and reduced Pt-Ce oxides supported on silica were prepared for their use in isomerization of n-hexane in the presence of hydrogen. These mixed oxides were either used alone or mixed with silica-supported heteropolyacids. The catalysts after oxidation, reduction, and catalytic tests were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, Fourier transform Raman spectroscopy, thermogravimetry, and N2 adsorption. The objective of the present study is the selection of the catalyst having the best isomer （branched） yield under optimum operating conditions （reaction temperature, reduction temperature, flow duration, etc. ）. The results show that the presence of the reduced oxides is not only beneficial for eliminating coke deposition but also effective for maintaining the structure of silica-supported heteropolyacids during reaction. Moreover, the better activity and the higher selectivity for isomers can be found with these samples.
出处
《催化学报》
SCIE
EI
CAS
CSCD
北大核心
2007年第12期1041-1046,共6页
关键词
杂多酸
正己烷
异构化
铂
铈
heteropolyacid
n-hexane
isomerization
platinum
cerium
