摘要
采用原位合成法制备了单晶ZSM-5/Silicalite-1核壳分子筛。考察了壳核比、核的粒径大小及硅铝比对核壳分子筛合成的影响,通过X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、NH3程序升温脱附(NH3-TPD)、低温N2吸附及异丙苯和1,3,5-三异丙苯裂解探针反应对分子筛进行表征,并考察了核壳分子筛在甲苯甲醇烷基化反应中的择形催化性能。结果表明,以大粒径、高硅铝比的分子筛为核有利于ZSM-5/Silicalite-1核壳分子筛的合成,且在甲苯甲醇烷基反应中,对二甲苯具有较高的选择性。
Single crystals of core-shell ZSM-5/silicalite-1 zeolite were synthesized via in-situ growth method. The effects of ratio of shell to core, core particle size, and ratio of SiO2 to AI203 on synthesis of core-shell zeolite were investigated. The zeolite synthesized were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), NH3 temperature-programmed desorption (NH3-TPD), N2 adsorption/ desorption isothermal and probe cracking reactions of isopropyl benzene and tri-isopropyl benzene. Moreover, the catalytic activities for alkylation of toluene over the zeolites were studied. It was found that cores with large particles and high ratio of SiO2 to Al2O3 led to formation of core-shell zeolite (ZSM-5/silicalite-1), which exhibited higher paraxylene selectivity in alkylation of toluene than conventional ZSM-5 zeolite.
出处
《化学反应工程与工艺》
CAS
CSCD
北大核心
2012年第6期519-524,共6页
Chemical Reaction Engineering and Technology
基金
国家重点基础研究发展计划项目(973计划)(2009CB623506)
关键词
核壳分子筛
择形催化
甲苯甲醇烷基化
core-shell zeolite
shape-selective catalysis
toluene alkylation