采用模板合成法制备了在脱铝Y分子筛纳米腔中含有Co, Mn,和Co/Mn混合物的三核金属簇合物的复合物催化剂,包括[Mn3(O)(CH3COO)6-(py)3]-Y,[Co3(O)(CH3COO)6-(py)3],[Co2Mn(O)(CH3COO)6-(py)3]-Y和[CoMn2(O)(CH3COO)6-(py)3]-Y],并运用傅里叶变换红外光谱、紫外-可见光光谱、前场扫描电镜、X射线衍射和原子吸收光谱对其进行了表征.包裹的金属簇合物在环己烯环氧化反应中表现出较高的催化活性,反应以H2O2/O2为氧化剂,在加热机械搅拌下进行,所得环氧化物产率在82.5%?90.7%.在该催化体系中, NaBr用作氧化助剂可以提高反应性能.在所制多相催化体系中,含单核的金属簇合物催化活性更高,其中以Mn3(O)-DAZY化合物的效率最高.各催化剂活性顺序为Mn3(O)-DAZY> Co3(O)-DAZY> Mn2Co(O)-DAZY> MnCo2(O)-DAZY.
Trinuclear metal clusters of Co, Mn and mixtures of Co/Mn including [Mn3(O)(CH3COO)6-(py)3]-Y, [Co3(O)(CH3COO)6-(py)3], [Co2Mn(O)(CH3COO)6-(py)3]-Y and [CoMn2(O)(CH3COO)6-(py)3]-Y] were prepared inside the nanocage of dealuminated Y zeolite by the template synthesis method. These catalysts were characterized by Fourier transform infrared, Ultraviolet-visible, field scanning elec-tron microscopy, X-ray diffraction and atomic absorption spectroscopy. The encapsulated metal clusters showed good catalytic activity in the epoxidation of cyclohexene with H2O2/O2. Epoxide yields were 82.5% to 90.7%. NaBr was used as a promoter for the oxidation. The homonuclear metal clusters showed higher catalytic activity than the others and the highest efficiency was with the Mn3(O)-DAZY compound. The catalytic activity order was Mn3(O)-DAZY> Co3(O)-DAZY>Mn2Co(O)-DAZY> MnCo2(O)-DAZY.
参考文献
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%