泽奥利特中的分子化学:泽奥利特Y支持的复合物催化剂的起源
1Department of Chemical Engineering and Materials Science, University of California, Davis, California 95616, USA.
Journal of the American Chemical Society
|September 13, 2008
概括
脱化烯酸支持单核复合体,用于稳定的乙烯二元化. 热酸站点和气之间的合作显著增强了催化活性.
科学领域:
- 不同质的催化剂.
- 材料科学是一种材料科学.
- 协调化学 协调化学
背景情况:
- 热石被广泛用作催化剂支.
- 调整热石的特性,如去光,可以改变催化性能.
- 复合体为各种催化转化提供了潜在的潜力.
研究的目的:
- 合成和表征在非发光的化石Y.上固定的单核复合体.
- 调查这些支持乙烯二聚化复合物的催化活性.
- 阐明石结构和共反应物的催化循环中的作用.
主要方法:
- 单核鲁复合物的合成:cis-Ru(acac) 2 ((C2H4) 2.
- 将复合物定在没有发光的化石Y上.
- 使用红外 (IR) 和扩展X射线吸收细结构 (EXAFS) 光谱学进行表征.
- 催化试验以乙烯二聚化,有或没有气辅料.
主要成果:
- 单核鲁复合物Ru ((acac) ((C2H4) 2 ((2+)) 通过Ru-O键连接到Al ((3+) 位点,成功地结到非发光的化石Y上.
- 实现的最大负载是每两个Al3+) 位点的一个复合体;更高的负载导致了物理吸收.
- 乙烯二聚化在气料中大约是600倍快,这表明了协同效应.
- 在反应开始时,acac联体解离并被一个Al ((3+) 位点捕获.
结论:
- 不发光的化石Y作为一个高效和统一的支持,用于精确的催化剂合成.
- 对于产生活性催化物种而言,热Al3+) 位点和的合作是至关重要的.
- 支持的单核复合体表现出稳定且高效的乙烯二聚化催化.
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