氨基MIL-101（Cr）强化CO2分离性能的混合基质膜优化制备  

Optimized fabrication of mixed matrix membranes based on amino-MIL-101（Cr） for highly efficient CO2 separation

作　　者：杨凯[1] 阮雪华[1] 代岩[1] 王佳铭 贺高红[1] YANG Kai;RUAN Xuehua;DAI Yan;WANG Jiaming;HE Gaohong(State Key Laboratory of Fine Chemicals,Research Center of Membrane Science&Technology,Dalian University of Technology,Dalian 116024,Liaoning,China)

机构地区：[1]大连理工大学精细化工国家重点实验室膜科学与技术研究开发中心

出　　处：《化工学报》2020年第1期329-336,共8页CIESC Journal

基　　金：国家自然科学基金项目(21978033,21606035);中国博士后科学基金(2019M650055)

摘　　要：金属有机骨架MIL-101(Cr)是大孔径、高孔隙率的新型膜材料,可显著提升混合基质膜的CO2渗透性,但其掺杂会明显降低选择性,有两方面原因:有机配体的CO2亲和性较低;填料干燥活化后再分散性差,易团聚形成缺陷。对此,首先以氨基对苯二甲酸为配体合成氨基MIL-101(Cr),提高溶解选择性,再采用先浇铸-后活化的制膜工艺,减少团聚缺陷。红外测试表明氨基填料成功合成;扫描电镜表明膜中填料分布均匀。掺杂15%(质量)氨基MIL-101(Cr)的乙基纤维素混合基质膜,CO2渗透系数达到200 barrer,比MIL-101(Cr)膜提高11.2%,较纯聚合物膜提高133.1%;同时,CO2/N2选择性达到23.9,比MIL-101(Cr)膜提高25.8%,较纯聚合物膜提高17.1%。综上,采用先浇铸-后活化的制膜工艺掺杂氨基MIL-101(Cr)填料,可同时提高混合基质膜的CO2渗透性和选择性。Metal-organic framework MIL-101(Cr)is a kind of new membrane materials with large pore size and high porosity,which can greatly enhance CO2 permeability for mixed matrix membranes.However,the blending with MIL-101(Cr)particles will lead to obvious decrease in CO2 selectivity,mainly caused by the following two reasons:terephthalic acid,as organic legend in MIL-101(Cr),is low in CO2 affinity relatively;particles after drying for activation,unable to be adequately dispersed in casting solution,would form defects in membranes.In response,two innovative attempts were carried through in this work.At first,amino-MIL-101(Cr)fillers were synthesized with 2-amino-terephthalic acid as organic legend,which could increase solution selectivity.Secondly,the retrofitted technique with MIL-101(Cr)activation after membrane fabrication was utilized to decrease defects caused by particle aggregation.FI-TR characterization revealed that amino-MIL-101(Cr)particles have been synthesized successfully.SEM images demonstrated that both MIL-101(Cr)and amino-MIL-101(Cr)particles can be evenly distributed in mixed matrix membranes through the retrofitted technique.Afterward,the membranes were fabricated with amino-MIL-101(Cr)blended in ethyl cellulose.Gas permeation tests revealed that the optimum particle loading is around 15%(mass).In this case,PCO2 is about 166 barrer(16.5%and 93.0%higher than MIL-101(Cr)blended and pristine membranes,respectively),whileαCO2/N2 is about 23.9(25.3%and 17.1%higher than that of MIL-101(Cr)blended and pristine membranes,respectively).On the whole,the blending with amino-MIL-101(Cr)particles through casting-activation approach can significantly enhance CO2 selective permeation in mixed matrix membranes.

关 键 词：二氧化碳 膜 分离 金属有机骨架 选择性 渗透系数 

分 类 号：TQ028.8[化学工程]