正己烷在成型无黏结剂5A分子筛上脱附特性研究  

Desorption Characteristic of n-Hexane Adsorbed on Binder-free 5A Zeolites

作　　者：杜旭东[1] 唐芸[1] 崔群[1] 王海燕[1] 姚虎卿[1] 

机构地区：[1]南京工业大学化学化工学院,江苏南京210009

出　　处：《高校化学工程学报》2013年第1期32-37,共6页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金(20876074);中石化项目(J106002)

摘　　要：用XRD测定成型无黏结剂5A分子筛(5A-1、5A-6)晶体结构;用微机差热天平测定正己烷在5A-1和5A-6上的TG-DTA特性曲线,研究其表观脱附活化能和脱附特性参数;在动态吸附/脱附实验装置上测定正己烷在5A-1和5A-6分子筛上的氦气吹扫脱附曲线,考察其吹扫脱附性能。结果表明:成型无黏结剂5A-1和5A-6均具有较强的5A分子筛XRD特征峰,无任何杂峰;5A-1相对于5A-6分子筛的结晶度为64%;正己烷在5A-1和5A-6分子筛上均存在两个(DTA)脱附峰,第一脱附峰对应的表观脱附活化能分别为33.44和39.35 kJ mol 1,第二脱附峰对应的表观脱附活化能分别为52.21和67.48 kJ mol 1;正己烷在5A-1和5A-6上的脱附温度不宜小于200℃;在200℃下,用氦气吹扫可使正己烷在5A-1和5A-6分子筛上的脱附完全,且正己烷在5A-1脱附性能优于5A-6。The crystal structures of binder-free 5A zeolite pellets（5A-1,5A-6） were determined by XRD,and the results show that the 5A-1 and 5A-6 zeolite pellets have strong XRD characteristic peaks of 5A zeolite and no other miscellaneous peak.The relative crystallinity of 5A-1 zeolite is 64% compared to that of the 5A-6 zeolite.The apparent desorption activation energy and desorption parameters of n-hexane adsorbed on binder-free 5A zeolite pellets were studied by thermo gravimetric differential analyzer（TG-DTA）.The helium purging desorption curves of n-hexane adsorbed on 5A-1 and 5A-6 zeolite pellets were studied by a dynamic adsorption and desorption experimental equipment.The TG-DTA profiles of n-hexane adsorbed on 5A-1 and 5A-6 zeolite pellets show two desorption peaks： the activation energies of the first desorption peak on 5A-1 and 5A-6 zeolite pellets are 33.44 kJ.mol.1and 39.35 kJ.mol.1,respectively,while the activation energies of the second desorption peak are 52.21 kJ.mol.1 and 67.48 kJ.mol.1,respectively.The suitable desorption temperatures of n-hexane adsorbed on 5A-1 and 5A-6 zeolite pellets all exceed 200℃.The n-hexane adsorbed on 5A-1 and 5A-6 zeolite pellets can completely desorbed by being purged with helium at 200℃,and the 5A-1 zeolite pellet has better desorption performance than that of 5A-6.

关 键 词：正己烷 成型无黏结剂5A分子筛 脱附活化能 氦气 吹扫 

分 类 号：TQ028.15[化学工程] TQ424.25