玻利酸后改性[Al]ZSM-5化物:特性,酸度和乙醇/乙烯转化
Zheng Li1, Daniel Dittmann1, Dennis Strassheim1
1Institute of Chemical Technology, University of Stuttgart, Stuttgart, Germany.
Chemistry (Weinheim an der Bergstrasse, Germany)
|February 21, 2026
概括
对[Al]ZSM-5热质的酸修饰改变了表面特性和酸度. 低负载增强乙醇转化为BTEX,这表明可能出现新的吸附材料.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 表面化学 表面化学
背景情况:
- 焦化物,特别是[Al]ZSM-5,是石化过程中的关键催化剂.
- 热石的后修改提供了一条调整其催化性能的途径.
- 酸被探索为MFI类型的化物的一种修饰剂.
研究的目的:
- 为了研究酸后修改对[Al]ZSM-5热带石特性的影响.
- 描述酸诱导的结构和酸位变化.
- 为了评估在催化反应中修改过的石的性能.
主要方法:
- 在不同负载下对[Al]ZSM-5化物进行酸后修饰.
- 表面积分析 (BET).表面积分析 (BET).
- 固态核磁共振 (NMR) 光谱 (B MAS NMR,H MAS NMR) 来探测物种和酸性位点.
- 使用三甲基啡氧化物 (TMPO) 的吸附性研究.
- 对甲醇,乙醇和乙烯转化进行催化试验.
主要成果:
- 酸修饰减少了表面积,并在高负载下导致晶体聚合.
- 11B MAS NMR表明在1.5%重量的酸中存在同型替代,在较高负载时表面沉积物.
- 布伦斯特酸位点 (BAS) 密度下降,而BAS强度仍然与原始热带石相似.
- 发现了易斯酸位点 (LAS),并且它们的性质在水合后发生了变化.
- 1.5%重量的酸加载改善了乙醇转化为BTEX和催化剂寿命.
结论:
- 酸的修饰改变了热酸度,引入了弱表面酸度和LAS.
- 1.5%重量负载在乙醇转化中表现出更好的性能,这表明特定的催化应用的潜力.
- 修改方法可能对开发适度条件操作的新吸附剂有价值.
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