负荷对以热为基础的催化剂的激活对甲脱水芳香化的影响
Josepha J G Kromwijk1, Job G A Vloedgraven1, Fleur Neijenhuis1
1Inorganic Chemistry and Catalysis Group, Institute for Sustainable and Circular Chemistry, Department of Chemistry, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, Netherlands.
概括
了解散是激活甲脱水芳香化 (MDA) 中W/ZSM-5催化剂的关键. 不同的负载需要特定的预处理以获得最佳的催化剂性能.
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:
- 基于石的催化剂对于甲脱水芳香化 (MDA) 是至关重要的.
- 这些催化剂中活性位点的确切性质仍在争论中,提出的结构包括或氧化物物种.
- 了解预催化剂结构及其激活对于改善催化剂性能至关重要.
研究的目的:
- 调查分散对MDA的W/ZSM-5催化剂激活的影响.
- 阐明预催化剂结构和激活通路之间的关系.
- 为了确定不同负载的最佳激活策略.
主要方法:
- 合成和描述W/ZSM-5催化剂的不同重量负载 (2,5,7和10 wt%).
- 在反应条件下对催化剂激活的评估.
- 应用不同的预处理方法 (惰性,还原性,热) 来研究它们对激活的影响.
- 分析散和前催化剂结构对激活时间和通路的影响.
主要成果:
- 观察到W/ZSM-5催化剂的意外长的激活时间.
- 发现低负荷 (2重量%) 可能会阻止由于单质物种的激活.
- 证明中等负载 (5-7%重量) 需要通过热预处理进行重组,以形成活性位点.
- 显示高负载 (10%重量) 需要一个减少步骤激活.
- 证实前催化剂结构显著影响催化剂激活.
结论:
- 催化剂的激活高度依赖于散和预催化剂结构.
- 考虑到负荷,定制的激活处理对于高效的W/ZSM-5催化剂性能至关重要.
- 这些发现可以导致优化工业规模的激活过程,节省时间和能源.
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