无模板剂两步法合成小颗粒ZSM-5沸石团聚体  

Synthesis of Zeolite ZSM-5 Small Particle Aggregates by a Two-Step Method in the Absence of an Organic Template

作　　者：黄先亮[1] 王正宝[1] 

机构地区：[1]浙江大学化学工程与生物工程学系,浙江杭州310027

出　　处：《催化学报》2011年第11期1702-1711,共10页

基　　金：浙江省科技厅项目(2009R50020)~~

摘　　要：在无模板剂存在下,以硅酸钠为硅源采用简单的变温两步法,通过控制高温预晶化时间,在转动烘箱中成功合成了小颗粒ZSM-5沸石团聚体.高温预晶化是为了加快反应液的成核,而低温晶化是为了获得小的分子筛晶体.运用X射线衍射,扫描电镜,NH3程序升温脱附和N2吸附-脱附等技术对合成的ZSM-5沸石进行了表征.与一步法合成的微米级颗粒相比较,两步法合成的小颗粒团聚体ZSM-5沸石具有较高比表面积和相同酸量.得到的沸石的Brnsted酸位占主要部分,Lewis酸位较少,也说明Al基本进入沸石骨架中.The preparation of zeolite ZSM-5 without using a template was extensively investigated. Zeolite ZSM-5 small particle aggregates were synthesized in the absence of a template using sodium silicate as the silica source and by controlling the nucleation time at high temperature with a simple two-step method in a rotating autoclave on a spit within an oven. The first stage at higher temperature consisted of accelerating the nucleation and the second stage at lower temperature consisted of obtaining small crystals in the absence of a template. The resulting zeolites were characterized by X-ray powder diffraction, scanning electron microscopy, ammonia temperature-programmed desorption, and N2 adsorption. Compared with the micron-sized zeolite crystals that are synthesized in the one-step method, zeolite ZSM-5 small particles prepared by the two-step method have a higher specific surface area and an equivalent acid site content. The sample synthesized by the two-step method mainly contains Br？nsted acid sites and a few Lewis acid sites indicating that Al is incorporated into the framework of the zeolite.

关 键 词：ZSM-5沸石 无模板剂 团聚体 两步合成法 晶粒大小 

分 类 号：O643.36[理学—物理化学]