表面固定ZnN网站作为高性能催化剂,用于在水中持续流动的Knoevenagel冷凝
Nan Yang1, Hongyan Zhu1, Xiaoxu Sun1
1College of Chemistry & Chemical Engineering, Central South University, Changsha, Hunan 410083, China.
ACS applied materials & interfaces
|December 12, 2023
概括
这项研究开发了一种新的异质催化剂,通过将--碳 (ZnN) 位点固定在 agarose aerogel 上. 强大的催化剂在温和,环保的条件下通过Knoevenagel凝结有效地产生α,β不和化合物.
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.
- 绿色化学 绿色化学
背景情况:
- 具有分散的金属--碳 (MNC) 位点的异质催化剂对于高效的化学合成至关重要.
- 之前的工作证明了通过表面固定来合理和高效地准备MNC催化剂.
- 开发强大且可扩展的异质催化剂对于工业应用至关重要.
研究的目的:
- 开发一种简单的策略,将 (Zn) 部位固定到阿加气凝 (AA) 上,用于异质催化.
- 为了研究Knoevenagel凝结中的固定ZnN位点的催化性能.
- 评估催化剂的稳定性,可扩展性和对工业生产的环境影响.
主要方法:
- 通过低温的凝结反应将ZnN位点固定在阿加气凝上.
- 使用IR,PXRD,XPS,同步电子粉末XRD和经过球形偏差校正的TEM进行了表征.
- 在使用批量和连续流反应器的Knoevenagel冷凝过程中对催化活性的评估.
主要成果:
- 证实了AA上的ZnN位点的表面固定,即使在高含量 (高达8%重量%) 中也没有观察到聚合.
- AA-ZnN-200催化剂 (4.62重量% Zn,在200°C处理) 显示出高的催化活性,产生高效率的α,β不和化合物.
- 连续流反应与malononitrile实现了高达99%的转化,显示了超过80小时的高催化剂稳定性和超过七个批次循环的可回收性.
结论:
- 建立了一种简单且可扩展的方法,用于在 agarose气凝上生产强大的异质 ZnN 催化剂.
- 催化剂可以有效,无分离,节能,环保地生产α,β不和化合物.
- 这种方法为工业合成有价值的化学中间体提供了一个实际的途径.
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