通过皮拉酸在酸复合的铁改性型摩登石上通过二甲基乙烯碳化增强稳定性
1Guangdong Provincial Key Laboratory of Green Chemical Product Technology, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
Molecules (Basel, Switzerland)
|April 13, 2024
概括
这项研究增强了二甲基乙烯 (DME) 碳化到甲基酸盐 (MA) 的方法,使用铁双金属改性. 这种新型催化剂表现出超过400小时的稳定运行,具有高的DME转换和MA选择性.
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:
- 甲基乙烯 (DME) 碳化成甲基乙酸 (MA) 对于化学合成至关重要.
- 提高催化剂的稳定性和选择性仍然是一个关键的挑战.
- 类型摩登石 (HMOR) 是一个潜在的催化剂支,但遭受失活.
研究的目的:
- 开发一种高度稳定和选择性的DME碳化催化剂.
- 为了研究pyrazole酸盐 (Pya·DL) 和葡萄酸 (DL) 复合的铁双金属修饰在HMOR上的作用.
- 了解催化剂停用和缓解策略的机制.
主要方法:
- 交换方法用于制备改性HMOR催化剂.
- 合成铁双金属复合物与Pya·DL和DL.
- 催化剂结构,特性和活性位点 (例如,LAS,BAS) 的表征.
- 在DME碳化反应中对催化剂进行长期测试.
主要成果:
- -Fe-DL-Pya-DL-HMOR (0.8) 催化剂在400多小时内实现了稳定的DME碳化.
- 实现了~70%的DME转换和>99%的MA选择性.
- 增强 Co-Fe 双金属的分散,形成新的易斯酸性位点 (LAS).
- Pya·DL消除了非框架,扩大了孔径,并防止了孔径堵塞.
- Pya·DL 屏蔽了布朗斯特酸部位 (BAS),抑制了碳沉积.
结论:
- 经过修改的HMOR催化剂对DME碳化表现出极高的稳定性和选择性.
- Co-Fe双金属和Pya·DL的协同作用是提高催化性能的关键.
- 催化剂的设计有效地解决了失活路径,为工业应用铺平了道路.
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