准备Fe-HMOR在12-MR通道中具有优选铁位置的Fe-HMOR,用于二甲基乙烯碳化
Wenrong Liu1, Yaquan Wang1, Lingzhen Bu1
1Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
Materials (Basel, Switzerland)
|May 25, 2024
概括
铁修改的摩登石 (MOR) 增强二甲基乙烯 (DME) 碳化. Fe-MOR催化剂在8个环中增加了布伦斯特德酸位,增加了活性并减少了焦炭形成.
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.
- 无机化学 无机化学 有机化学
背景情况:
- 蒙登石的8个环 (8-MR) 中的布伦斯特酸位是二甲基乙烯 (DME) 碳化过程的关键.
- 选择性增强这些部位对于提高催化性能至关重要.
研究的目的:
- 通过单水热合成合成Fe-修饰的摩登石 (Fe-MOR).
- 调查Fe替代对布伦斯特德酸位分布和DME碳化中的催化活性的影响.
主要方法:
- 使用EDTA-Fe复合物的Fe-HMOR的一热水合成.
- 使用XRD,FTIR,UV-Vis,拉曼,XPS,NH3-TPD和Py-IR进行表征.
- 评估DME碳化中的催化活性,并使用TG/DTG分析已耗尽的催化剂.
主要成果:
- 在MOR的12-MR通道中,Fe原子选择性地替代了Al.
- 在8-MR中,0.01的最佳Fe/Si比率最大化了布伦斯特德酸位点.
- Fe-MOR (Fe/Si = 0.01) 的活性是HMOR的三倍.
- 添加Fe抑制了碳沉积和重焦的形成.
结论:
- 铁的修饰提供了一个实际的策略,以提高mordenite的催化性能.
- 将选择性Fe纳入MOR通道优化了DME碳化活性位点.
- 通过抑制焦炭形成,Fe-MOR催化剂显示出更好的稳定性.
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