高硅ZSM-5分子筛上择形催化合成4,4’-二甲基联苯  

SYNTHESIS OF 4,4'-DIMETHYLBIPHENYL OVER SILICA-RICH ZSM-5 ZEOLITE CATALYSTS

作　　者：王会娟[1] 刘民[1] 赵岩[1] 宋春山[1,2] 郭新闻[1] 

机构地区：[1]大连理工大学精细化工国家重点实验室,辽宁大连116012 [2]宾夕法尼亚州立大学能源与矿物工程系及能源研究所,美国宾夕法尼亚州大学城16802

出　　处：《石油学报（石油加工）》2010年第4期506-511,共6页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：教育部新世纪优秀人才支持计划(NCET-04-0268);"111"引智计划项目资助

摘　　要：以高硅(n(Si O2)/n(Al2O3)=373)HZSM-5分子筛为母体,采用浸渍法制备了一系列NH4F/Pt复合改性催化剂(w2)Pt-(w1)F-ZSM-5,以4-甲基联苯(4-MBP)与甲醇的烷基化为探针反应,考察了NH4F用量、Pt用量、NH4F改性后盐酸洗涤以及向反应体系添加水蒸气对反应的影响。结果表明,经复合改性后,0.75Pt-HCl-5F-ZSM-5催化剂用于4-MBP甲基化反应,其稳定性及二甲基联苯(DMBPs)的产率得到明显提高,反应2 h DMBPs产率为9.6%,反应20 h后,4-MBP转化率为9.1%,4,4’-DMBP选择性可达76.1%。而未改性HZSM-5催化剂上,反应2 h DMBPs产率为4.2%。向反应体系添加水蒸气可进一步提高(w2)Pt-(w1)F-ZSM-5催化剂的稳定性和4,4’-DMBP选择性,反应30 h 4,4’-DMBP选择性仍高达90%。A series of silica-rich HZSM-5（n（SiO2）/n（Al2O3）=373） samples modified with NH4F/Pt were employed for the alkylation of 4-methylbiphenyl（4-MBP） with methanol to 4,4＇-dimethylbiphenyl（4,4＇-DMBP） under fixed-bed down-flow conditions.The results showed that silica-rich ZSM-5 treated with NH4F/Pt could significantly improve the catalytic stability and the yield of dimethyl biphenyl（DMBPs） in 4-MBP methylation.Over HZSM-5 catalyst,the yield of DMBPs was 4.2% after 2 h reaction,while the yield of DMBPs could reach 9.6% over 0.75Pt-HCl-5F-ZSM-5 catalyst after 2 h reaction.After 20 h reaction,the 4-MBP conversion was about 9.1%,and the selectivity of 4,4＇-DMBP was about 76.1% over the modified catalyst.Adding water vapor into reaction system could further improve the catalytic stability of the catalyst and selectivity of 4,4＇-DMBP.After 30 h reaction,the selectivity of 4,4＇-DMBP was still up to 90%.

关 键 词：择形选择性 4-甲基联苯 4 4’-二甲基联苯 高硅ZSM-5 氟化铵 铂 

分 类 号：O643[理学—物理化学]