在Cu/ZnO/Al催化剂上的CO2化中NH3-诱导的挑战2
Xuan Bie1, Yukun Pan2, Xiaowei Wang2
1Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Beijing Key Laboratory of CO2 Utilization and Reduction Technology, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, P.R. China.
氨 (NH3) 可逆地抑制逆水气转移 (RWGS) 反应,但在长时间暴露后会导致不可逆的催化剂失活. 提出了一种新的NH3分解策略来缓解这种抑制.
科学领域:
- 催化和化学工程 催化和化学工程
- 材料科学 材料科学 材料科学
背景情况:
- 来自生物质/废物气化和碳捕获的工业气体流含有像氨 (NH3) 这样的杂质.
- 这些杂质可以对催化剂性能产生负面影响,例如逆水气转移 (RWGS) 等反应.
研究的目的:
- 研究氨 (NH3) 对RWGS反应动力学和催化剂结构的影响.
- 了解Cu/ZnO/Al2O3催化剂在NH3的存在下失活的机制.
- 提出一种减轻NH3抑制的策略.
主要方法:
- 在商用Cu/ZnO/Al2O3催化剂上研究了RWGS反应.
- 研究了不同NH3度和温度的影响.
- 在长时间暴露于NH3后,分析的催化剂结构发生变化.
- 提出并评估了一种NH3分解方法.
主要成果:
- 氨 (NH3) 通过抑制碳酸化和二氧化碳脱吸,可逆抑制了二氧化碳的转化.
- 较高的NH3度和较低的温度加剧了抑制.
- 长时间 (100+小时) 暴露于1.4%的NH3导致了不可逆转的催化剂失活.
- 暴露于NH3导致Cu+位点的丧失和Cu和ZnO组件的空间分离.
- 建议将氨分解为N2和H2作为缓解策略.
结论:
- 氨 (NH3) 对RWGS催化具有重大挑战,导致可逆性活性损失和不可逆性失活.
- 了解NH3的结构影响对于设计强大的催化剂至关重要.
- 催化剂的失活可以通过在反应之前分解NH3来减轻.
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