高溶剂含量第1凝固浴停留时间对PVDF膜结构和性能的影响  

EFFECT OF HIGH-CONCENTRATION FIRST COAGULATION BATH RETENTION TIME ON THE STRUCTURES AND PROPERTIES OF PVDF MEMBRANE

作　　者：李薇[1] 王磊[1] 孟晓荣[2] 王旭东[1] 原巍[1] 黄丹曦[1] 

机构地区：[1]西安建筑科技大学环境与市政工程学院,陕西西安710055 [2]西安建筑科技大学理学院,陕西西安710055

出　　处：《水处理技术》2011年第9期51-54,共4页Technology of Water Treatment

基　　金：教育部博士点基金项目-博导类(20096120110010);国家自然科学基金项目(51008243);陕西省"13115"科技创新工程重大科技专项(2010ZDKG-56);陕西省重点实验室项目(2010JS028);陕西省教育厅专项基金项目(09JK543);西部建筑科技国家重点实验室(筹)开放研究基金(10KF08)

摘　　要：以聚偏氟乙烯(PVDF)、聚乙烯吡咯烷酮(PVP)、二甲基乙酰胺(DMAc)为铸膜液体系,采用高含量溶剂DMAc水溶液作为第1凝固浴,水为第2凝固浴组成的双凝固浴制备PVDF中空纤维膜。通过扫描电镜(SEM)形貌观察,纯水水通量和BSA截留率测试,探讨了第1凝固浴停留时间对PVDF-PVP中空纤维膜性能与结构的影响。结果表明,随着膜丝在高溶剂含量第1凝固浴中停留时间从0变化至10 s,膜丝纯水通量在2 s时下降,之后持续增加,而BSA截留率不断降低。SEM显示随停留时间延长,膜表面孔隙率增加,亚层指状孔增多,大孔孔径增大,亚层海绵结构变得疏松。在停留时间为10 s时,膜水通量达315 L.m-2.h-1,BSA截留率86%,可做为制备高通量PVDF超滤膜的最佳成形条件。Polyvinylidene fluoride （PVDF）/polyvinylpyrrolidone （PVP）/N,N-dimethylacetamide （DMAc） solutions composite hollow fiber membrane were fabricated by the dual-bath coagulation method, using high concentrations of DMAc/water solution as the first coagulation bath, water for the second coagulation bath. The effect of first coagulation bath residence time on the performance and microstructure of PVDF-PVP hollow fiber membrane were investigated with scanning electron microscopy （SEM）, pure water flux and Bovine Serum Albumin （BSA） solute rejection performance in this paper, The experimental results indicated that with the first coagulation bath residence time changes from 0 to 10 s, pure water flux was reduced in the 2 s, and then turned to increase, while the BSA retention rates had decreased. The SEM images showed the sponge-like structure was looser with more and bigger macrovoid structure at the sub-layer, and the membrane upper structure varied from dense to porosity as the residence time prolonging. The pure water flux amounted to 315 L.m-Z.h ~ and the BSA rejection rate was moderate when the residence time was 10s, which was the best formation condition for high-permeance PVDF ultrafiltration membrane.

关 键 词：聚偏氟乙烯 中空纤维膜 双凝固浴法 第1凝固浴 停留时间 

分 类 号：TQ028.8[化学工程]