丙烯直接气相氧化过程中Ag/TS-1催化剂上活性银物种的分布  

Distribution of active silver species of Ag/TS-1 catalyst on direct gas-phase epoxidation of propylene

作　　者：王瑞璞[1] 郭新闻[1] 王祥生[1] 王传付[1] 郝敬泉[1] 

机构地区：[1]大连理工大学精细化工国家重点实验室,催化化学与工程系,辽宁大连116012

出　　处：《化工学报》2005年第8期1484-1491,共8页CIESC Journal

基　　金：教育部科学技术重点项目(99150);国家重点基础研究发展规划项目(G2000048009)~~

摘　　要：在常压固定床、石英反应器中,以丙烯直接气相氧化反应为探针,考察了硅烷化处理及TS-1中模板剂对Ag/TS-1催化性能的影响.同时,采用UV-Vis、ICP和TEM等手段对其进行了表征.结果表明:在丙烯直接气相氧化过程中,载体TS-1硅烷化后所制备的Ag/TS-1的催化性能增强.通过硅烷化处理负载2%SiO2,制备的Ag/TS-1的丙烯转化率可达2.1%,环氧丙烷选择性98.4%.用TS-1原粉(含有模板剂)所制备的Ag/TS-1不具有环氧化性能.分子筛内外表面的银物种均具有环氧化性能,但内表面的银物种在丙烯气相氧化过程中起决定性的作用.The effects of silylation treatment and the template of TS-1 on the catalytic properties of Ag/ TS-1 were investigated in a fixed bed, quartz reactor at ambient pressure, using the gas-phase epoxidation of propylene with hydrogen and oxygen as a probe, Moreover, the catalysts were characterized by UVVis, ICP and TEM, The results showed that, during the direct gas-phase epoxidation of propylene, the catalytic properties of Ag/TS-1 could be improved when TS-1 was silylanized, When 2%SiO2 was loaded on TS-1, 2, 1% propylene conversion with 98, 4% selectivity to propylene oxide （PO） was obtained over Ag/TS-1, The Ag/TS-1 did not show any catalytic selectivity to PO, when the TS-1 powder （with template） was used as the support, Both inner and outer silver species of Ag/TS-1 showed catalytic properties, however, the inner ones were the key active species in the gas-phase epoxidation of propylene,

关 键 词：丙烯 Ag/TS-1 环氧丙烷 分子氧 环氧化 

分 类 号：O643.32[理学—物理化学]