在异质原子分散ReO4/SiO2催化剂上选择性甲醇碳化为酸
Ji Qi1, Jordan Finzel1, Hossein Robatjazi1
1Department of Chemical Engineering, University of California, Santa Barbara, Santa Barbara, California 93117, United States.
Journal of the American Chemical Society
|July 22, 2020
概括
这项研究引入了一种新型的异质催化剂,使用原子分散的在上进行甲醇碳化到酸,在没有腐蚀性化物的情况下实现高选择性和活性.
科学领域:
- 催化剂
- 材料科学
- 化学工程
背景情况:
- 甲醇碳化到酸通常使用具有腐蚀性化物促进剂的同质催化剂.
- 开发高效的异质催化剂对于工业应用至关重要.
研究的目的:
- 开发一种无化物,异质的催化剂,用于甲醇碳化为酸.
- 在基基上研究原子分散氧化的性能和机制.
主要方法:
- 使用三甲醇胺在SiO2上合成原子分散的ReO4.
- 使用AC-STEM,UV-VIS光谱和XAS进行表征.
- 反应性测量,动力分析,现场FTIR和现场XAS.
主要成果:
- 在SiO2上原子分散的ReO4具有>93%的选择性,转化率>60%.
- 在气相甲醇碳化中,催化剂表现稳定60小时.
- 添加Rh促进剂进一步提高了选择性到96%以上.
结论:
- 在惰性SiO2上原子分散的ReO4代表了一种有前途的无化物异质催化剂,用于酸生产.
- 拟议的机制包括甲醇激活和CO插入.
- 这项工作为酒精碳化中的新异质催化剂开辟了道路.
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