聚乙烯胺/埃洛石纳米管混合基质膜的制备及其CO_2/N_2分离  

Preparation of PVAm mixed matrix membranes by incorporating halloysite nanotubes for CO_2/N_2 separation

作　　者：侯蒙杰 张新儒[1,2] 王永洪 李晋平[1,2] 刘成岑 凌军[3] HOU Mengjie;ZHANG Xinru;WANG Yonghong;LI Jinping;LIU Chengcen;LING Jun(College of Chemistry and Chemical Engineering,Taiyuan University of Technology,Taiyuan 030024,Shanxi,China;Shanxi Key Laboratory of Gas Energy Efficient and Clean Utilization,Taiyuan 030024,Shanxi,China;Technology Centre,China Tobacco Yunnan Industrial Co.,Ltd.,Kunming 650231,Yunnan,China)

机构地区：[1]太原理工大学化学化工学院,山西太原030024 [2]气体能源高效清洁利用山西省重点实验室,山西太原030024 [3]云南中烟工业有限责任公司技术中心,云南昆明650231

出　　处：《化工学报》2018年第9期4106-4113,共8页CIESC Journal

基　　金：国家自然科学基金青年基金(21506140);山西省煤层气联合基金(2015012009);中国博士后基金(2016M601289);山西省留学人员科技活动项目择优资助经费~~

摘　　要：制备高性能的气体分离膜,是实现CO_2高效回收的关键。为了提高CO_2分离膜的性能,将中空管状结构的埃洛石纳米管(HNTs)添加到聚乙烯胺(PVAm)中配制涂膜液,并将PVAm-HNTs涂膜液涂覆到聚砜(PSf)超滤膜上制备PVAm-HNTs/PSf混合基质膜。其中PSf超滤膜作为支撑层,PVAm-HNTs致密涂层作为功能层,功能层结构与形态对CO_2分离具有关键作用。采用XRD、SEM对HNTs的结构与形态进行表征,并借助FTIR和SEM对膜的形态与结构进行分析。在进料气为纯气条件下,系统地研究了HNTs添加量、进料压力、PVAm-HNTs涂层厚度对PVAm-HNTs/PSf膜的CO_2分离性能影响,并考察了混合基质膜的CO_2/N_2混合气分离性能。结果显示:在水溶液中显示正电性的PVAm与负电性的HNTs具有较好的界面相容性。HNTs添加量为1%(质量)、PVAm-HNTs湿涂层厚度为50μm的混合基质膜,表现出最优的CO_2分离性能。在进料气压力为0.1 MPa、测试温度为25℃、CO_2/N_2(15/85,体积比)混合气进料的条件下,膜的CO_2渗透速率为178 GPU,CO_2/N_2选择性为83;该膜具有较好的稳定性,经过120 h运行后,渗透性和选择性仍能保持稳定。The preparation of gas separation membranes with high permselectivity is the key for CO2 efficient recovery.To improve the CO2 separation performance of membrane,halloysite nanotubes(HNTs)with hollow and tubular structure were incorporated into polyvinylamine(PVAm)aqueous solution to fabricate PVAm-HNTs coating solutions.PVAm-HNTs/polysulfone(PSf)mixed matrix membranes(MMMs)were prepared by coating PVAm-HNTs solutions on PSf ultrafiltration membranes.The PSf membrane is the supporting layer,and PVAm-HNTs coating layer is the functional layer,which is the key for CO2 separation.The structure and morphology of HNTs were characterized by XRD and SEM.The morphology and structure of the membranes were analyzed by FTIR and SEM.The effects of HNTs content,feed pressure,and the thickness of PVAm-HNTs coating layer were systematically investigated by using pure CO2 and N2 pure gas.The CO2/N2[15/85(volume)]mixed gas separation performance also were investigated.The good interfacial interaction is attributed to the electrostatic attraction between PVAm and negatively charged HNTs.At testing temperature of 25℃and feed gas pressure of 0.1 MPa,PVAm-HNTs/PSf-1%(mass)MMMs with wet coating thickness of 50μm exhibited long-term performance stability,and the CO2 separation performance maintained high CO2 permeability of 178 GPU with CO2/N2 selectivity of 83 for CO2/N2 mixed gas over 120 h.

关 键 词：埃洛石纳米管 聚乙烯胺 膜 烟道气 CO2捕集 

分 类 号：TQ028.8[化学工程]