用自由配体法制备了一系列固载席夫碱钻配合物的Y型分子筛催化剂(Co-X2—salicyhexen-Y).其中,X2代表H、OCH2、Cl、Br、NO2基团,Salicyhexen代表双取代水杨醛缩环己二胺类席夫碱。采用X射线衍射、FTIR、UV-vis和热分忻方法对制备的催化剂进行了表征。结果表明,席夫碱钻配合物以原来的结构固载于分子筛超笼中,对分子筛的框架结构没有影响。研究了以分子氧作氧化剂,上述催化剂在苯乙烯环氧化反应中的催化性能,考察了席夫碱钻配合物取代基对封装和催化性能的影响。实验结果表明,该系列催化剂在苯乙烯环氧化反应中表现出高的活性和稳定性;席夫碱芳环上的H被吸电子基团取代后,降低了Y分子筛超笼中封装的钴配合物的量.但能改善催化活性。
A series of zeolite Y encapsulated Co-X2-salicyhexen complex catalysts, where salicyhexen represents salicylaldehyde-1,2-cyclohexanediamine and X represents H, OCH3, Cl, Br or NO2, were prepared by flexible ligand method and characterized by XRD, FTIR, UV-vis and thermal analysis. The results indicated that the complexes could form and be encapsulated in the supercages without affecting the zeolite framework structure. The effects of substituents on encapsulation and catalytic activity of the encapsulated complexes were also investigated. The prepared catalysts exhibitted high activity and stability in the epoxidation of styrene with molecular oxygen. Substitution of the aromatic hydrogen atom of the Schiff base ligand with electron withdrawing group decreased the amount of the complex encapsulated in the zeolite cavities, but could improve the catalytic activity of the encapsulated complex.