表面修改对基支持的Ti催化剂的作用,用于用蒸汽相过氧化氧化环烯的氧化
Sol Ahn1, Sarah K Friedman2, Justin M Notestein2,3
1Department of Chemical Engineering, Chung-Ang University 84 Heukseok-ro, Dongjak-gu Seoul 06974 Republic of Korea solahn@cau.ac.kr.
RSC advances
|August 14, 2024
概括
催化剂的表面修改影响了循环烯环氧化作用的过氧化激活. 接种特定的有机组可以抑制或增强催化剂活性和产品选择性.
科学领域:
- 催化剂是一种催化剂.
- 表面化学 表面化学
- 有机合成 有机合成
背景情况:
- 路易斯酸催化剂,如支持的 (Ti-SiO2),对于氧化反应至关重要.
- 不同质催化剂的表面修饰可以调整它们的反应性和选择性.
- 过氧化 (H2O2) 是用于环氧化反应的环保氧化剂.
研究的目的:
- 研究移植有机部分对Ti-SiO2催化剂的影响.
- 了解表面修饰如何影响H2O2激活在蒸汽相环烯环氧化过程中.
- 为了将接种组的性质与催化剂性能和产品分布相关联.
主要方法:
- Ti-SiO2催化剂的合成.
- 在Ti-SiO2表面上植入不同的有机功能群 (性,非极性,极性近极性).
- 使用改性催化剂和H2O2.2,对环烯的蒸汽相环氧化.
- 使用分析技术分析反应速率,产品产量和选择性.
主要成果:
- 移植一种基 (1H,1H-perfluoro-octyl) 显著抑制了Ti-SiO2.2的催化活性.
- 移植一个非极性八基增强了环氧化率.
- 接种一个极性近极的三乙烯糖醇单甲基乙醇组也提高了速率,并将选择性转移到trans-1,2-cyclohexanediol.
结论:
- 用有机分子对Ti-SiO2催化剂表面修改提供了调整催化性能的途径.
- 接种组的性质在H2O2激活和反应结果中起着关键作用.
- 优化的表面功能化可以提高环氧化率和循环烯氧化中的直接选择性.
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