揭示了在NO2的酸功能化CeO2催化剂上的活性站点的动态行为减少
Pan Zhang1, Aling Chen1, Tianwei Lan1
1International Joint Laboratory of Catalytic Chemistry, State Key Laboratory of Advanced Special Steel, College of Sciences, Shanghai University, No.99 Shangda Road, Shanghai 200444, P. R. China.
Langmuir : the ACS journal of surfaces and colloids
|June 14, 2023
概括
酸和硫酸 (CeO2) 催化剂增强了氨的选择性催化还原 (NH3-SCR). 布伦斯特酸位点是去除氧化的关键,并促进氧化还原循环.
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
- 环境化学环境化学
背景情况:
- 使用氨 (NH3-SCR) 的氧化 (NOx) 的选择性催化降解 (SCR) 对于排放控制至关重要.
- 了解基于CeO2的催化剂中的活性位点动态对于优化NH3-SCR性能至关重要.
- 由于其氧化还原特性,CeO2催化剂被广泛研究为NH3-SCR.
研究的目的:
- 研究NH3-SCR过程中CeO2催化剂中酸位和氧化还原动力学的作用.
- 阐明酸化和硫化对催化剂活性的影响.
- 为改造的CeO2催化剂提供对NH3-SCR的机制性见解.
主要方法:
- 用酸化和硫化CeO2催化剂的制备.
- 使用操作光谱来探测反应条件下的催化剂行为.
- 分析酸位 (路易斯和布伦斯特德) 和氧化还原位 (Ce4+/Ce3+) 之间的相互作用.
主要成果:
- 易斯和布伦斯特德酸位都对NH3-SCR至关重要.
- 在或硫酸盐修饰后,Brønsted酸位成为主导活性位点.
- 酸功能化增强了Ce4+/Ce3+氧化还原循环,改善了NOx的减少.
- 布伦斯特德酸位的变化显著影响NOx去除效率.
结论:
- 布伦斯特酸位点在NH3-SCR中发挥着至关重要的作用,而不是修改后的CeO2催化剂.
- CeO2的酸功能化促进了对NOx减排至关重要的氧化还原特性.
- 这项研究提供了对NH3-SCR中活性位点机制的更深入的理解,指导了未来的催化剂设计.
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