硅钨杂多酸在中孔全硅分子筛HMS上的固载及其催化性能  

CATALYSTS COMPRISING 12 SILICOTUNGSTIC ACID IMMOBILIZED ON A HEXAGONAL MESOPOROUS SILICAS (HMS) AND THEIR CATALYTIC PROPERTIES

作　　者：楚文玲[1] 杨向光[1] 叶兴凯[1] 吴越[1] 

机构地区：[1]中国科学院长春应用化学研究所

出　　处：《催化学报》1997年第3期225-229,共5页

摘　　要：用十二烷基胺代替传统的季铵盐合成了中孔全硅分子筛ＨＭＳ，并将硅钨杂多酸（ＳｉＷ１２）浸渍固载在ＨＭＳ上．用ＸＲＤ，ＦＴ－ＩＲ以及ＮＨ３－ＴＰＤ等手段对ＨＭＳ及不同负载量和焙烧温度的负载催化剂进行了表征．即使在固载量为５０％的ＳｉＷ１２／ＨＭＳ中，ＳｉＷ１２仍保持其Ｋｅｇｇｉｎ结构并均匀分布在载体表面上，没有ＳｉＷ１２晶相生成．同时，在气－固相反应体系中研究了固载在ＨＭＳ上的ＳｉＷ１２在合成乙酸丁酯中的催化性能．实验结果表明，２００℃焙烧可以增强杂多酸与ＨＭＳ内表面之间的相互作用，从而使其对酯化反应活性具有一定的影响，并且固载催化剂在较低反应温度下具有较高的酯化活性，且性能稳定，有一定的应用前景．Hexagonal mesoporous silicas (HMS) is a novel mesoporous molecular sieve which is synthesized by dodecylamine as a template replacing conventional quaternary ammonium ion surfactant. The supported catalysts with different loadings and calcined at different temperatures, consisting of 12 silicotungstic acid (SiW 12 ) immobilized on HMS have been prepared and characterized by X ray diffraction, FT IR and NH 3 temperature programmed desorption. It shows that SiW 12 retains the Keggin structure on the HMS surface and forms finely dispersed HPA species. No HPA crystal phase is developed even with SiW 12 loading as high as 50%. And in the esterification of n butanol by acetic acid, it can be found that the loaded amount of SiW 12 and calcination temperature have a significant effect on catalytic activity. Especially, SiW 12 /HMS catalysts show a higher activity and stability at lower temperature and hold some promise of practical application.

关 键 词：中孔分子筛 HMS 酯化 催化剂 硅钨杂多酸 

分 类 号：TQ426.91[化学工程] O643.36[理学—物理化学]