磷钨杂多酸及其铯盐上的常温正戊烷异构化反应  

Pentane Isomerization at Ambient Temperature on H_3PW_12O_40 and its Cesium Salts

作　　者：孙渝[1] 乐英红[1] 高滋[1] 

机构地区：[1]复旦大学化学系,上海200433

出　　处：《化学学报》1998年第8期792-798,共7页Acta Chimica Sinica

基　　金：国家攀登计划资助课题

摘　　要：制备了一系列用于正戊烷异构化的磷钨杂多酸及其铯盐催化剂,并对它们进行了详细的物性表征、实验结果表明,Cs含量对催化剂的比表面、孔结构、热稳定性和表面酸量有显著的影响.考察了所制备的催化剂上常温下正戊烷异构化反应的活性和选择性.利用催化剂表征结果讨论了活化温度和Cs含量等因素对催化性能的影响.磷钨杂多酸及其铯酸式盐属固体超强酸.根据35℃时正戊烷异构化反应速率常数估测H_3PW_(12)O_(40)和Cs_(2.25)H_(0.75)PW_(12)O_(40)的酸强度H_0约在-13～-12.4之间.A series of 12 - tungstophosphoric heteropolyacid and its cesium salts as n - pentane isomerization catalysts were prepared and characterized with various techniques. The BET surface area,pore stucture, thermal stability and surface acidity of the catalysts are influenced strikingly by the amount of Cs in the heteropolyacid salts. The catalytic activity and selectivity of the catalysts for n -pentane isomerization at ambient temperature were investigated. The effects of activation temperature and Cs content on catalytic behavior of the catalysts were discussed in relation to the characterization results. 12- tungstophosphoric heteropolyacid and its acidic cesium salts are solid superacids. The acid strengths of H3PW12O40 and Cs2.25 H0.75PW12O40 are estimated to be in the range of H0=-13 - -12.4 by measuring the rate constants of n - pentane isomerization reaction at 35℃.

关 键 词：磷钨杂多酸 铯盐 正戊烷 异构化 超强酸 催化剂 

分 类 号：O643.36[理学—物理化学] O623.11[理学—化学]