分子筛的酸性对正十二烷烃临氢异构化的影响  

Influences of Zeolite Acidity on Hydroisomerization of N-dodecane

作　　者：陈宜俍[1] 朱阳阳[1] 徐军[1] 郭士岭[1] 张鹏飞[1] 韩丽[1] 商建超[1] 

机构地区：[1]郑州大学化工与能源学院,河南郑州450001

出　　处：《郑州大学学报（工学版）》2013年第5期121-124,共4页Journal of Zhengzhou University（Engineering Science）

基　　金：NSFC-河南人才培养联合基金U1204215

摘　　要：对正十二烷的临氢异构化进行了研究,分别选用ZSM-22、L沸石、SAPO-11 3种一维孔道的分子筛作为载体,采用浸渍法制备Pt/分子筛催化剂,并对催化剂进行了XRD和NH3-TPD表征,同时考察酸性质对于异构化反应的影响.结果表明:载体的总酸量影响催化剂的活性,较高的总酸量使催化剂具有较高的活性;异构化产物的选择性与催化剂的酸强度有关,较强的酸性中心使反应朝裂解的方向进行,降低了正十二烷临氢异构化反应的选择性;较弱的酸中心有利于正十二烷临氢异构化反应,强度较弱的酸中心的数量与正十二烷临氢异构化反应选择性有较好的关联.弱酸中心的数量多,并且所占的比例最大时,异构产物的选择性才会高.该研究为提高和改进大分子正构烷烃临氢异构化催化剂的酸性能提供了较好的思路.The hydroisomerization of n-dodecane was studied in this paper. Pt/zeolite catalysts, which respec- tively used monodimensional pore molecular seives, ZSM-22, L and SAPO-11 as support, were prepared by impregnation method and characterized by XRD and NH3-TPD. The influences of their acidity on hydroisomer- ization were investigated as well. The results showed that the total acid amount of the supports affect the activi- ty of the catalysts, a higher total amount of acid in the catalyst having a higher activity. The selectivity of hydroisomerization is related to the acid strength, strong acidic centers make reaction toward the cleavage di- rection, reducing the i-dodecane selectivity; the weak acid sites conducive to the hydroisomerization of n-do- decane, and the number of weak acid sites correlated well with i-dodecane selectivity in hydroisomerization. When weak acid sites is the largest proportion in the total acid amount, the heterogeneous product selectivity will be higher. This study will provide a better idea to enhance and improve catalyst acidic, which is used in the the hydroisomerization of macromoleeular paraffin.

关 键 词：异构化 L SAPO-11 ZSM-22 选择性Pt 

分 类 号：X703.1[环境科学与工程—环境工程]