碱处理制备介孔-微孔沸石分子筛的影响因素及其应用研究进展

Influence factors for preparation of meso-microporous zeolites by alkali-treatment and their research progress

综述了碱处理制备介孔-微孔沸石分子筛的影响因素,包括碱处理条件、沸石分子筛硅铝比和模板剂对碱处理脱硅形成介孔的影响。评述了碱处理所制备介孔-微孔沸石分子筛在应用方面所取得的进展,重点介绍了它们在烷基化、异构化、裂化和醇烃化等催化反应中的应用。通过碱处理引入介孔可极大地缩短分子在沸石微孔道中的扩散距离,从而增强表观催化反应活性及提高催化剂的稳定性。提出了今后研究的重点为:阐明碱处理引入介孔的形成机理和碱处理对分子筛骨架结构、酸性的影响,拓展碱处理制备介孔-微孔沸石分子筛的应用范围。

This review deals with various factors,including alkali-treatment conditions and Si/Al ratios and templates of parent zeolites,affecting the mesoporosity formed in zeolites by means of alkali treatment.In addition,the progress of the applications of meso-microporous zeolites prepared by alkali-treatment is presented,focusing on their applications to the catalytic reactions of alkylation,isomerization,cracking,and alcohol alkylation.The introduction of mesopores in zeolites by alkaline treatment can significantly shorten the characteristic length of molecule diffusion through micropores in zeolites,enhancing the apparent activity of the catalytic reactions and improving the catalytic stability of zeolites.Further studies,including clarification the mechanism of the introduced mesoporosity by alkali-treatment,the effect of alkali-treatment on the framework and acidity,as well as extending the application scope of the prepared meso-microporous zeolites,are expected.