在多个接口的纳米结构催化剂上对Tandem Alkene Hydroformylation机制的洞察
Ji Su1, Chenlu Xie2, Chen Chen2
1Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|September 3, 2016
概括
使用新型CeO2-Pt@mSiO2纳米结构的双重催化增强了制的选择性. 这项研究阐明了这种机制,为设计先进的异质催化剂铺平了道路.
科学领域:
- 不同质的催化
- 纳米材料科学
- 化学反应工程
背景情况:
- 双重催化使单个纳米结构内的选择性序列反应成为可能.
- 之前通过甲醇和乙烯生产的研究由于未定义的催化剂而缺乏机理理解.
- 在双重化中实现高选择性仍然是一个挑战.
研究的目的:
- 设计和合成一个稳定,明确的3D催化剂 (CeO2-Pt@mSiO2) 用于研究双重水合形成.
- 研究影响乙烯转化为的产品选择性的机制和因素.
- 探索这种催化剂在其他基如烯和1-丁烯的协同化中的应用.
主要方法:
- 一个具有定义接口的三维CeO2-Pt@mSiO2催化剂的合成.
- 在各种条件下通过双重水合基化对乙烯转化为的研究.
- 使用不同 (烯,1-丁烯) 的比较研究和对照实验.
- 详细的机制分析以了解选择性增强.
主要成果:
- CeO2-Pt@mSiO2催化剂在以乙烯生产中达到80%的选择性.
- 发现乙烯的存在缓解了甲醇的分解,抑制了的积累,有利于的形成.
- 反应中间体在催化界面之间有效地迁移,促进直接的化.
- 烯和1- 布的类似化物产生也被观察到.
结论:
- 这项研究阐明了使用CeO2-Pt@mSiO2的协同化增强选择性背后的机制.
- 协同效应和改变反应路径是这种双重催化方法的关键优势.
- 这项工作为选择性化学转换的新型异质催化剂的合理设计提供了基础.
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