ZSM-22、β和丝光沸石介孔改性对比研究  

Comparative Investigation on Mesopore Modification of ZSM-22,Beta and MOR Zeolites

作　　者：李洋洋[1] 王颖敏[2] 徐丽颖[1] 刘金环[1] 张园园[1] 金英杰[1,2] 

机构地区：[1]辽宁石油化工大学化学与材料科学学院,抚顺113001 [2]辽宁石油化工大学石油化工学院,抚顺113001

出　　处：《人工晶体学报》2014年第6期1576-1582,共7页Journal of Synthetic Crystals

基　　金：辽宁省自然科学基金(200922180);国家自然科学基金(21171083)

摘　　要：用碱-酸处理法对ZSM-22(TON)、β(BEA)和丝光(MOR)型沸石进行介孔改性。研究沸石结构与介孔率、脱硅选择性、介孔生成效率的关系,定量阐述了不同沸石的脱硅反应选择性、改性过程的脱硅选择性及脱硅效率。结果表明,改性沸石具有微孔-介孔结构和介孔尺度分布均一化特性。按沸石结构比较,脱硅反应选择性和改性过程脱硅选择性均满足MOR<BEA≤TON,且改性过程脱硅选择性均大于90.6%;与比表面相关的脱硅效率:TON<MOR<BEA。沸石的骨架密度和生成焓绝对值越小、微孔可接近性越好,介孔率和脱硅效率越高。BEA型改性沸石的比表面、比孔容和介孔孔径分别为468.2 m2/g、0.66 cm3/g和5.6 nm。Zeolites with MOR,BEA and TON structures were mesoporous modified by alkaline-acid treatments.The mesoporosity,desilication selectivity and desilication efficiency versus structure of zeolites were studied,and the selectivity of desilication reaction,the whole desilication selectivity towards the modification process,and desilication efficiency were quantitatively elucidated.As a result,these modified zeolites are provided with microand mesoporous structures and feature a uniform mesopore distribution.According to the different zeolite structures,selectivities both towards desilication reaction and desilication process follow the same sequence of MOR BEA TON,the desilication-process selectivity is always larger than 90.6% for each of the three structures,and the desilication efficiency relative to the specific surface area of mesoporous structure ranges as TON MOR BEA.The microporous zeolite with the lower framework density and formation enthalpies from oxides but higher channel accessibility exhibits both of the higher mesoporosity and desilication efficiency.The representative sample of modified zeolite BEA has the significant mesopore structure：viz.the specific surface area of 468.2 m2/g,specific pore volume of 0.66 cm3/g and diameter of 5.6 nm.

关 键 词：沸石结构 介孔率 脱硅选择性 脱硅效率 

分 类 号：O643[理学—物理化学]