在氨基合成过程中RuCs/MgO催化剂中的结构-活性关系
Linus Biffar1, Niklas Martin Brinker1, Peter Pfeifer1,2
1Institute for Micro Process Engineering, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany.
ChemSusChem
|July 24, 2025
概括
提升通过增加金属含量来增强氨合成的催化剂. 然而,催化剂失活与漂水有关,特别是在存在氧杂质的情况下.
科学领域:
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 工业氨合成需要高温和高压才能有效转化反应物.
- 用金属促进的以为基础的催化剂通过促进分离,为降低能源需求提供了潜力.
- 了解 (Ru) 和 (Cs) 物种的行为对于优化催化剂性能至关重要.
研究的目的:
- 研究RuCs/MgO和Ru/MgO催化剂中的Ru和Cs物种的结构变化.
- 在不同压力下分析还原和氨合成期间的催化剂行为.
- 在暴露于氧杂质时检查催化剂失活机制.
主要方法:
- 使用X射线吸收光谱 (XAS) 探测催化剂结构.
- 在催化剂还原和氨合成过程中进行了实验.
- 催化剂的性能在纯气料下和25 ppm氧杂质下在高达19 bar的压力下进行了评估.
主要成果:
- 在两种催化剂中都观察到RuO2,分散的RuOx和金属Ru物种之间的相互转换.
- 促进增加了金属Ru含量,减少分散的RuOx,并导致更高的氨产量.
- 暴露在氧气中将Cs+转化为水合物种,并且不可逆转的失活是由于出水引起的.
结论:
- 促进有效提高金属Ru含量和氨合成活性.
- 催化剂的失活主要是由泄漏引起的,氧杂质加剧了这种情况.
- 这项研究提供了关于基于Ru的氨合成催化剂的结构-活性-失活关系的见解.
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