的非氧化脱使用结合支持的Pt站点通过原子层沉积合成
1Department of Chemical Engineering, Faculty of Engineering, Middle East Technical University, Ankara, Turkiye.
Turkish journal of chemistry
|March 28, 2024
概括
将添加到催化剂中显著提高了烯在脱过程中的选择性和稳定性. 这种双金属催化剂设计提高了生产有价值化学品的催化性能.
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:
- 的无氧化脱到烯对于生产有价值的化学品至关重要.
- (Pt) 基催化剂正在积极研究,通过修改活性位点来调整性能.
- 引入第二种金属可以改变Pt位点的电子密度,影响催化活性.
研究的目的:
- 研究 (B) 添加在用于脱的基于Pt的支持催化剂中的作用.
- 通过原子层沉积 (ALD) 合成和描述双金属Pt-B/SiO2催化剂.
- 评估B对Pt位点特性,催化性能,选择性和稳定性的影响.
主要方法:
- 通过顺序半循环ALD合成B/SiO2和PtB/SiO2催化剂.
- 使用ICP-OES,DRIFTS-CO和时间解析的XANES进行了表征.
- 用550°C的固定床反应器进行气脱的催化试验.
主要成果:
- 的添加增加了Pt负荷的2.2倍,并提高了Pt电子密度和可还原性.
- PtB/SiO2催化剂显示出更好的烯选择性 (87%vs. 80%) 和近三倍的增强稳定性.
- 最初的催化活性没有显著改变,这表明B主要影响选择性和稳定性.
结论:
- 双金属 Pt-B/SiO2 催化剂在非氧化式脱中表现出优异的性能.
- 增强的烯选择性归因于有利于烯脱吸.
- 改善的稳定性与缓解的焦炭形成有关,使PtB/SiO2成为一个有前途的催化剂.
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