TS-1催化的环己酮氨氧化反应研究

Ammoximation of Cyclohexanone Catalyzed by TS-1

环己酮氨氧化反应是己内酰胺生产的绿色化学过程。催化剂的稳定性是该过程工业化的关键之一。本文考察了温度、溶剂、催化剂的加入量以及过氧化氢的加入方式等对TS - 1催化环己酮氨氧化反应的影响 ,确定了反应的优化条件。为了研究反应介质对催化剂稳定性的影响 ,在比较苛刻的条件下、有无有机溶剂下对催化剂进行了氨处理。用扫描电镜、X -射线衍射、红外光谱和紫外 -可见光谱对催化剂进行了表征。研究结果表明 ,反应介质对催化剂的粒径、结晶度、活性中心结构等具有破坏作用 ,而有机溶剂有效地限制了这些破坏作用。

The stability of the catalyst is one of the most important issues in scaling-up the environmental friendly process of the ammoximation of cyclohexanone. In the present work, the reaction conditions were optimized. To study the effects of ammonia and organic solvents on the structure stability of the catalyst, TS-1 samples were deliberately pretreated under severe conditions in ammonia solution with or without organic solvents and characterized with SEM, XRD, FTIR, Uv-vis reflectance spectroscopy, etc. The results revealed that ammonia tends to destroy the crystallite size, crystallinity and Ti-containing active sites of TS-1, but the presence of organic solvents remarkably limits this damaging effect of ammonia.