U型PEBA中空纤维渗透汽化膜组件及其优先透醇性能

U-shaped PEBA hollow fiber pervaporation membrane module and its alcohol permselectivity performance

以聚偏氟乙烯(PVDF)中空纤维超滤膜为基膜,构建了具有U型结构的中空纤维膜组件.采用浸渍-提拉法将聚醚酰胺嵌段共聚物(PEBA)组装到PVDF膜表面,获得了具有优先透醇性能的PEBA/PVDF中空纤维渗透汽化复合膜.分析和表征了组装前后PVDF膜表面的形貌和化学性质,研究了PEBA质量分数、干燥温度、干燥时间和提拉速率等制备条件对复合膜性能的影响,考察了进料温度和进料流速等操作条件的影响.此外,考察了具有U型结构的PEBA/PVDF中空纤维渗透汽化复合膜的稳定性以及对ABE发酵液模拟体系的分离性能.结果表明,PEBA/PVDF中空纤维复合膜在分离质量分数1%正丁醇/水体系时,渗透通量为2 720 g/(m~2·h),分离因子为17.38,表现出良好的优先透醇渗透汽化性能.

Polyvinylidene fluoride(PVDF)hollow fiber ultrafiltration membrane was used to construct a hollow fiber membrane module with U-shape structure.The polyether amide block copolymer(PEBA)was assembled on the surface of PVDF membrane by dip-coating and lifting method.The PEBA/PVDF hollow fiber composite membrane was obtained with alcohol permselectivity.The morphology and chemical properties of PVDF membrane before and after assembly were analyzed and characterized.The effects of preparation conditions such as PEBA concentration,drying temperature?drying time and lifting speed on the separation performance of composite membrane were studied・The effects of operating conditions such as feed temperature and feed flow rate on the membrane were also investigated・In addition,the stability of PEBA/PVDF hollow fiber pervaporation composite membrane module with U-shaped structure and the separation performance of ABE fermentation broth simulation system were investigated.The results show that PEBA/PVDF hollow fiber composite membrane has a permeation flux of 2720 g/(m2·h)and a separation factor of 17.38 in the separation of 1%(mass fraction)n-butanol/water system,showing a good pervaporation performance.