摘要
通过接枝将离子液体1-烷基-3-（三乙氧基硅丙基）咪唑硫酸氢盐（烷基：甲基、乙基、丁基）在MCM-36分子筛表面进行负载改性,通过~1H-NMR、FT-IR、XPS、TGA、XRD、SEM、BET和正丁胺回滴法等对改性的MCM-36（MCM-36-ILs）进行表征。结果表明酸性离子液体通过化学作用在MCM-36表面进行负载;负载离子液体的催化剂可以在350℃以下稳定存在而不分解;负载离子液体能增加固体酸催化剂表面的酸量,但比表面积和平均孔容有一定程度的降低。Sip模型能很好描述异丁烷、1-丁烯在MCM-36负载离子液体前后固体酸催化剂上的平衡吸附量。异丁烷、1-丁烯在离子液体改性的MCM-36上的吸附性能与离子液体结构、离子液体负载量及催化剂表面特性等有关。负载酸性离子液体可以调节MCM-36上烷烯吸附比（nI/nO,相同压力下分子筛上吸附的异丁烷和1-丁烯的物质的量之比）。经1-乙基-3-（三乙氧基硅丙基）咪唑硫酸氢盐负载改性的MCM-36具有较好的烷烯吸附比调节性能,其表面的烷烯吸附比最高可以达到0.95,接近于烷基化反应所需的化学计量比。催化剂表面烷烯吸附比的改善有利于提高催化剂的性能和目标产物的选择性。
MCM-36 was modified by grafting ionic liquids （ILs） 1-alkyl-3-（triethoxysilylpropyl） imidazolium hydrogen sulfates （alkyl：methyl, ethyl,butyl）. The modified MCM-36 catalysts （MCM-36- ILs） were characterized by ^1H-NMR, FT-IR, XPS, TGA, XRD, SEM, BET and an n-butylamine titration method. The results show that the ILs were immobilized on MCM-36 by chemical bonds. MCM-36-ILs were stable below 350 ℃. The immobilizing of acidic ILs led to an increase of acid amount and a certain decrease of specific surface area and average pore volume of MCM-36. The equilibrium adsorption capacities of isobutane and 1-butene on MCM-36 and MCM-36-ILs could be described well by Sip model. The adsorption behaviors of isobutane and 1-butene on MCM-36-ILs were affected by the structure of IL, the loading amount of IL and the surficial properties of solid catalyst. The adsorption molar ratio of isoparaffin to olefin （ni/no） on MCM-36 could be adjusted by supporting acidic ionic liquids. In this study,an adsorption nI/nO of 0.95 on MCM-36 loaded by 1-ethyl-3-（triethoxysilylpropyl）imidazolium hydrogen sulfate was achieved,
出处
《华东理工大学学报（自然科学版）》
CAS
CSCD
北大核心
2016年第6期743-751,共9页
Journal of East China University of Science and Technology
基金
国家自然科学基金(21276163
21576168)
