接种的金属素作为单位表面有机金属催化剂
Justin M Notestein1, Enrique Iglesia, Alexander Katz
1Department of Chemical Engineering, University of California at Berkeley, Berkeley, California 94720-1462, USA.
Journal of the American Chemical Society
|December 17, 2004
概括
植入于二氧化上的金属色作为高活性和选择性的异质催化剂,用于烯环氧化. 这些表面定催化剂表现出增强的稳定性和单位行为,表现优于同质的同行.
科学领域:
- 不同质的催化剂.
- 表面有机金属化学
- 材料科学 材料科学 材料科学
背景情况:
- 在有机合成中,开发高效和选择性的烯环氧化催化剂至关重要.
- 同质催化剂经常面临分离和回收的挑战.
- 表面有机金属化学提供了一条固定活性催化物种的途径.
研究的目的:
- 为了合成和表征在二氧化上植入的金属二,作为异质催化剂.
- 评估它们在使用有机氧化物对烯的环氧化中的活性和选择性.
- 研究表面密度和催化剂结构对催化剂性能的影响.
主要方法:
- 使用表面有机金属方法将卡利沙-Ti(IV) 前体移植到上.
- 使用光谱方法进行表征,以确认催化剂结构和连接性.
- 用不同的氧化物对循环烯环氧化物的动力分析.
主要成果:
- 在不同密度的二氧化表面上成功地将金属二氧化接种.
- 谱学证据证实了催化前后的Ti(IV) - 素链接.
- 与同质类型相比,固定催化剂的活性和选择性更高,速度常数独立于表面密度.
结论:
- 金属酸接种的二氧化是一种强大的类型的异质催化剂,用于环氧化.
- 这种方法可以创建稳定的,单位催化剂,精确到原子水平.
- 这便于合理设计先进的异质氧化物催化剂.
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