Regulation of isobutane/1-butene adsorption behaviors on the acidic ionic liquids-functionalized MCM-22 zeolite  

作　　者：Keting Jin Tao Zhang Shaojun Yuan Shengwei Tang 

机构地区：[1]Multi-phase Mass Transfer and Reaction Engineering Lab,College of Chemical Engineering,Sichuan University,Chengdu 610065,China

出　　处：《Chinese Journal of Chemical Engineering》2018年第1期127-136,共10页中国化学工程学报（英文版）

基　　金：Supported by the National Natural Science Foundation of China(21576168,21276163)

摘　　要：The adsorption ratio of isobutane/1-butene on the catalyst surface is one of the most important factors for the C4 alkylation process. Regulation of isobutane/1-butene adsorption ratio on the zeolite-supported acid catalyst is a big challenge for catalyst preparation. To regulate the isobutane/1-butene adsorption ratio, four types of ionic liquid （i.e., IL） with different alkyl chain lengths and different acid group numbers were synthesized and were subsequently immobilized onto the MCM-22 zeolite. The as-synthesized IL-immobilized MCM-22 （i.e., MCM-22-IL） was characterized by FT1R, TGA, BET, XPS and XRD, and their adsorption capacities and adsorption molar ratios of isobutane to l-butene （I/O） were investigated to correlate with surface features of MCM-22-IL Results showed that the immobilization of ILs led to a decrease of specific surface area and pore volume. But the surface density of acid groups was increased and the adsorption molar ratio of isobutane/1-butene （I/O） was significantly im- proved by the immobilization of ionic liquids. The adsorption molar ratio of I/O is substantially improved from 0.75 to above 0.9 at 300 kPa upon immobilizing ILs. Although the alkyl chain length oflLs was found to have little effect on the adsorption molar ratio of I/O, the increase of acid group numbers led to a dramatic decrease in the adsorption I/O ratio. The results illustrated that immobilizing ionic liquids is an effective way to modify the textural, chemical and morphological properties of MCM-22. Accordingly, the immobilization of ionic liquids provides a novel and a feasible way to regulate the adsorption I/O ratio on an adsorbent or a solid catalyst.The adsorption ratio of isobutane/1-butene on the catalyst surface is one of the most important factors for the C_4 alkylation process. Regulation of isobutane/1-butene adsorption ratio on the zeolite-supported acid catalyst is a big challenge for catalyst preparation. To regulate the isobutane/1-butene adsorption ratio, four types of ionic liquid(i.e., IL) with different alkyl chain lengths and different acid group numbers were synthesized and were subsequently immobilized onto the MCM-22 zeolite. The as-synthesized IL-immobilized MCM-22(i.e., MCM-22-IL)was characterized by FTIR, TGA, BET, XPS and XRD, and their adsorption capacities and adsorption molar ratios of isobutane to 1-butene(I/O) were investigated to correlate with surface features of MCM-22-IL. Results showed that the immobilization of ILs led to a decrease of specific surface area and pore volume. But the surface density of acid groups was increased and the adsorption molar ratio of isobutane/1-butene(I/O) was significantly improved by the immobilization of ionic liquids. The adsorption molar ratio of I/O is substantially improved from 0.75 to above 0.9 at 300 kPa upon immobilizing ILs. Although the alkyl chain length of ILs was found to have little effect on the adsorption molar ratio of I/O, the increase of acid group numbers led to a dramatic decrease in the adsorption I/O ratio. The results illustrated that immobilizing ionic liquids is an effective way to modify the textural, chemical and morphological properties of MCM-22. Accordingly, the immobilization of ionic liquids provides a novel and a feasible way to regulate the adsorption I/O ratio on an adsorbent or a solid catalyst.

关 键 词：Adsorption Catalyst Ionic liquids lsobutane 1-Butene 

分 类 号：O643.36[理学—物理化学] O647.3[理学—化学]