通过O2激活AgPd1-合金催化剂以乙烯化
Nicholas Golio1, Andrew J Gellman1
1Department of Chemical Engineering W.E. Scott Institute for Energy Innovation, Carnegie Mellon University 5000 Forbes Ave., Pittsburgh, Pennsylvania 15213, United States.
ACS catalysis
|November 29, 2023
概括
添加氧气显著提高银合金 (AgPd) 乙烯化催化剂的性能. 这种增强发生在各种合金组成和条件下,激活以前不活跃的催化剂.
科学领域:
- 不同质的催化剂.
- 材料科学是一种材料科学.
- 表面化学 表面化学
背景情况:
- 乙烯化是一种关键的工业过程.
- 银合金 (AgPd) 是潜在的催化剂,但它们的性能因成分和条件而异.
- 氧在AgPd合金催化中的作用尚未完全理解.
研究的目的:
- 为了研究氧气对乙烯化AgPd合金的催化活性的影响.
- 为了映射整个AgPd组合分布的乙烯化活性.
- 了解氧气诱导的反应机制的基本变化.
主要方法:
- 制造一个组成的扩散合金薄膜 (CSAF),覆盖Ag-Pd组合物 (xPd = 0 到 1).
- 在不同温度,压力和有/没有氧气下对催化乙烯化活性进行高通量选.
- 对的反应顺序的测量,以探测反应机制.
主要成果:
- 没有氧气,只有具有xPd≥0.90的富含Ag合金显示活性.
- 添加15 Torr O2显著增加了所有组合物的催化活性,使最大转换率翻了一番,并将激活合金降至xPd = 0.6.
- 添加氧气导致活性合金上的的反应顺序接近零,这表明反应途径发生了变化.
结论:
- 乙烯化中的AgPd合金的催化活性对操作条件,特别是氧气的存在非常敏感.
- 氧显著提高了AgPd催化剂的性能,可能是通过促进Pd分离和激活化表面.
- 该研究展示了一种通过控制氧气暴露来提高催化剂性能的新方法.
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