W-ZSM-5催化剂C_4烯烃裂解制丙烯催化性能研究  

Research on Catalytic Performance of W-Modified HZSM-5 Catalyst for C_4 Olefin Cracking

作　　者：张建军[1] 周钰明[1] 杨抗震[1] 唐梦涵[1] 张一卫[1] 

机构地区：[1]东南大学化学化工学院,江苏南京211189

出　　处：《分子催化》2008年第3期236-241,共6页Journal of Molecular Catalysis(China)

基　　金：中国石化安庆分公司(G2520-06-ZS-0290);教育部新世纪优秀人才计划(NCET-04-0482)资助项目

摘　　要：采用浸渍法制备了W-ZSM-5催化剂,用X-射线衍射(XRD)、N2吸附、NH3-TPD和H2-TPR等表征手段,研究了W的添加对HZSM-5催化剂物化性质的影响,并考察了W-ZSM-5催化剂在C4烯烃催化裂解制丙烯反应中的催化性能.结果表明,W的添加中和了催化剂的部分强酸位,降低了催化剂的酸性和酸强度,抑制了芳构化和氢转移等副反应的发生,增强了催化剂的抗积炭性能,促进了催化裂解过程中歧化反应的发生,有利于提高丙烯的选择性和收率.当W含量为3.2%时,催化剂的丙烯选择性和收率值达到最大,分别为47.4%和41.3%.The W-Modified HZSM-5 catalyst was prepared and characterized by X-ray diffraction, N2 adsorption, Temperature-programmed desorption of ammonia and Temperature-programmed reduction. Its catalytic performance for C4 olefin was also investigated. The results show that the acid density and the acid strength of ZSM-5 catalyst decreased with the modification of ZSM-5 zeolite by W, especially the strong acid. When used as a catalyst for Butene cracking, the W-ZSM-5 catalyst with suitable concentration of W is able to restrain the reaction of aromatization and hydrogen transfer, prevent the catalyst from coking, in favor of the metathesis between ethane and 2-butene during the catalytic cracking process and increase the catalytic activity. It is found that the propylene selectivity and yield could reach the maximum of 47.4% and 41.3% respectively, when the W content is 3.2%.

关 键 词：ZSM-5 钨 C4烯烃 催化裂解 丙烯 

分 类 号：O643.32[理学—物理化学]