高度隔离过渡金属催化剂及其烯烃环氧化研究

 介绍了过渡金属杂原子分子筛的骨架杂原子表征、用离子注入法和化学嫁接法制备高度隔离过渡金属催化剂及其催化烯烃环氧化研究的结果．基于共振拉曼原理，用紫外共振拉曼光谱明确鉴别了TS－1，Fe－ZSM－5和V－MCM－41等分子筛中的骨架杂原子．用离子注入法和化学嫁接法制得具有高度隔离过渡金属离子的非杂原子分子筛催化剂．烯烃环氧化反应结果表明，所制得的催化剂显示出优良的催化性能．

Epoxidation of Olefins on Catalysts with Highly Isolated Transition Metal Ions

The framework transition metal ions in microporous and mesoporous materials such as Ti Silicalite 1 (TS 1), Fe ZSM 5 and V MCM 41 have been identified based on the UV resonance Raman spectroscopy. It is pointed out that the conventionally used IR (Raman) band at 960 cm -1 is not directly associated with the framework titanium ions in TS 1, while a resonance Raman band at 1?125 cm -1 is found to be essentially due to the asymmetric vibration of framework Ti-O-Si. To mimic the highly isolated transition metal ions in the framework of zeolites, Ti/SiO 2, Fe/SiO 2 and V/SiO 2 catalysts were prepared using ion beam implantation and Ti/SiO 2 and Si/Ti/SiO 2 catalysts were prepared by chemical grafting. These catalysts show pretty high activity and selectivity for the epoxidation of styrene and cyclohexene using H 2O 2 as the oxidant. This work further confirms that the highly isolated transition metal ions are selective and active for the selective oxidation using H 2O 2 (ROOH) as the oxidant and the catalysts with highly isolated transition metal ions can be prepared with alternative methods instead of zeolitic synthesis.