化工学报 ›› 2005, Vol. 56 ›› Issue (8): 1484-1491.

• 催化、动力学与反应器 • 上一篇    下一篇

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

王瑞璞;郭新闻;王祥生;王传付;郝敬泉   

  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
  • 出版日期:2005-08-25 发布日期:2005-08-25

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

WANG Ruipu;GUO Xinwen;WANG Xiangsheng;WANG Chuanfu;HAO Jingquan   

  • Online:2005-08-25 Published:2005-08-25

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.

关键词: 丙烯, Ag/TS-1, 环氧丙烷, 分子氧, 环氧化

Abstract: 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 UV-Vis, 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.

Key words: 丙烯, Ag/TS-1, 环氧丙烷, 分子氧, 环氧化