影响SAPO-11分子筛焙烧前后晶胞空间群变化的因素  

Factors Affecting the Spacer Changes of SAPO-11 Zeolite

作　　者：刘月明[1] 张凤美[2] 舒兴田[2] 何鸣元[1] 

机构地区：[1]华东师范大学离子液体化学研究中心,上海200062 [2]中国石油化工股份有限公司石油化工科学研究院,北京100083

出　　处：《催化学报》2003年第10期783-787,共5页

摘　　要：从合成参数出发 ,详细考察了不同因素对SAPO 11分子筛焙烧前后晶胞空间群变化的影响 .发现成胶方式、成胶温度、模板剂组成、晶化温度、晶化时间及分子筛产物组成均是影响分子筛晶胞空间群变化的因素 .MAS NMR分析结果表明 ,分子筛的微观结构决定了分子筛晶胞空间群的变化 ,Si( 4Si)区增加 。SAPO 11 zeolite with special pore structure and tunable acidity shows its potential application in hydrocarbon isomerization. The SAPO 11 zeolite with spacer Icm2 after calcination has higher catalytic activity for hydrocarbon isomerization. The factors affecting the spacer changes of SAPO 11 zeolite before and after calcination were investigated carefully. The stronger the ability to retain spacer Icm2 of SAPO 11 after calcination, the higher the intensity ratio of I 21 3° / I 21 85° . The gelation process, gelation temperature, template type and composition, crystallization temperature and time, and zeolite composition were investigated in order to understand their effects on the spacer changes of SAPO 11 zeolite before and after calcination. The result showed that higher Si content, lower crystallinity, higher gelation temperature, lower crystallization temperature, proper gelation process and template composition are more convenient to synthesize SAPO 11 retaining spacer Icm2 after calcination. 29 Si MAS NMR was used to investigate the spacer changes of SAPO 11 zeolite after calcination. It was showed that the higher the Si(4Si) area, the stronger the trend to retain spacer Icm2. It was suggested the two atoms connecting to form two 6 rings in SAPO 11 framework, it might be the Si coordinated with another four Si atoms, and it was convenient to prevent the changes of elliptical channels. The optimized conditions to synthesize SAPO 11 zeolite with spacer Icm2 after calcination and proper acidity were suggested, and the SAPO 11 zeolite with excellent performance in hydrocarbon isomerization was synthesized.

关 键 词：SAPO-11分子筛 合成 晶胞结构 空间群 

分 类 号：O643.3[理学—物理化学]