苯在Silicalite-1分子筛上的吸附和脱附  

Adsorption and desorption of benzene in silicalite-1

作　　者：班红艳[1] 代敏[2] 张晓彤[2] 桂建舟[2] 宋丽娟[2] 孙兆林[1] 

机构地区：[1]兰州大学化学化工学院,甘肃兰州730000 [2]辽宁石油化工大学石油化工学院,辽宁抚顺113001

出　　处：《兰州大学学报（自然科学版）》2005年第1期69-73,共5页Journal of Lanzhou University(Natural Sciences)

基　　金：国家自然科学基金(20343006)辽宁省科学基金(002076)辽宁省教育厅攀登计划(20051016)资助项目

摘　　要：采用重量法研究了苯在silicalite-1分子筛上303 K时的吸附和室温至400℃的热脱附行为.结果表明苯在303 K时的吸附和脱附等温线有两个台阶,并且出现了滞后环.DTG曲线展示了当每单位晶胞吸附量小于4个分子时只有一个热脱附峰;而当每单位晶胞吸附量大于4个分子时有两个热脱附峰,并且在TG曲线上每单位晶胞吸附量为4个分子处有一个拐点.DTG曲线揭示了苯在silicalite-1上存在两种吸附位置,吸附在不同位置上的分子之间存在平衡关系,不同升温速率对热脱附几乎无影响.Adsorption of benzene from silicalite-1 at 303 K was studied using Intelligent Gravimetric Analyzer (IGA). At the same time, thermodesorption between ambient temperature and 400℃ was conducted. The results showed that the adsorption and desorption isotherms had two steps and a hysteresis loop. The DTG curves showed only one mass loss peak when the amount sorbed was less than 4 molecules per unit cell. But when it was more than 4 molecules per unit cell, two mass loss peaks appeared on the DTG curves, and there was an inflection about 4 molecules per unit cell on the TG curves. The DTG curves of benzene revealed the existence of two different binding sites. There was some equilibrium between molecules bound at different sites. The difference of heating rate had less influence on thermodesorption, but the peak temperatures changed slightly.

关 键 词：脱附 SILICALITE-1 热重 苯 

分 类 号：O655.9[理学—分析化学]