This study investigated physicochemical properties of ZSM-35 zeolites calcinatedunder different temperatures with template agents and their application in 1-hexane skeleton isomerization. The results show that calcination temperature difference leads to different removal percentages of the template agent. When the calcination temperature is below 450℃, the template agent is decomposed and cannot be completely removed, and the zeolites show high 1-hexene skeletal isomerization selectivity. When the calcination temperature is up to 550℃, the template agent is completely removed but the iso-olefines yield decreases significantly with high percentage of byproducts. BET, XRD, TPO, NH3-TPD, TG-DTG and Py-IR characterization suggests that the chamber walls covered by the template agent are exposed after template agent removal, which makes the specific surface area and total acid of the catalysts increase. Therefore, the average active site of the catalysts increases that results in the increase of conversion.However, the removal of the template agent results in more small mesopores which lead to more dimerization and copolymerization. Furthermore, the template agent removal can also lead to the generation of new L acid centers which increases side effects and results in lower catalyst selectivity.%研究了不同温度焙烧的含模板剂ZSM-35分子筛的物化性质和1-己烯骨架异构化反应性能.研究结果表明,不同焙烧温度的焙烧会使ZSM-35分子筛的模板剂发生不同程度的脱除,当温度低于450℃ 时,焙烧会使模板剂发生分解反应,不会使模板剂残留物完全脱除,此时分子筛表现出较高1-己烯骨架异构选择性;焙烧温度升至550℃ 后,分子筛中的模板剂可完全脱除,但异构烯烃的收率显著降低,副反应产物明显增加.通过BET、XRD、TPO、NH3-TPD、TG-DTG、吡啶红外的表征表明,随着模板剂的脱除,暴露出被其覆盖的腔壁,使分子筛的比表面积增大,催化剂总酸量增加,从而使得单位催化剂的活性位增加,催化剂转化率增大;但模板剂脱除的同时会新增小孔径介孔,这些介孔会促使二聚、共聚等副反应的发生,不利于异构化反应的进行;且模板剂脱除会产生一部分新的L酸中心,L酸中心的出现也会增大催化剂的副反应活性,降低催化剂的选择性.
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