【摘要】 采用简单、易重现的两步后合成法成功制备了Ce-Beta分子筛.制备过程中,H-Beta分子筛首先经过脱铝处理得到Si-Beta分子筛,然后再以异丙醇铈为前驱体,通过干法浸渍的途径向Si-Beta分子筛引入Ce(IV).利用XRD,FT-IR,UV-Vis和1H MAS NMR等对其结构进行了表征,结果表明,Ce(IV)物种以四配位的形式成功引入Beta分子筛的骨架,Ce原子进入分子筛骨架的机理通过DRIFT光谱得以证实.通过环氧化合物水合制备1,2-二醇反应对所制的Ce-Beta催化剂进行了催化性能评价.更多还原

【Abstract】 Ce(IV)-containing zeolite Beta was successfully prepared by a reproducible and scalable two-step post-synthesis strategy. This consists of creating vacant T sites that are associated with silanol groups by the dealumination of the H-Beta zeolite and a subsequent dry impregnation of the resultant Si-Beta zeolite with cerium(IV) isopropoxide. XRD,FT-IR,UV-Vis and 1H MAS NMR confirmed that Ce(IV) was successfully incorporated into the Beta zeolite framework by the post-synthesis procedures and that they exist as isolated atoms with tetrahedral coordination. The mechanism of Ce incorporation into the framework of Beta zeolite was confirmed by DRIFT spectroscopy. The ring-opening hydration of epoxides to their corresponding 1,2-diols was selected as a model reaction for an evaluation of the catalytic performance of the as-synthesized Ce-Beta zeolite.更多还原