部分碳化PTFE/PVDF中空纤维膜的制备及油水分离性能研究  

Preparation of partially carbonized PTFE/PVDF hollow fiber membrane and its oil-water separation performance

作　　者：张紫莹 肖芬 盛明鑫 董永全 ZHANG Ziying;XIAO Fen;SHENG Mingrin;DONG Yongquan(National and Local Joint Engineering Research Center for Heavy Metal Pollutant Control and Resource Utilization,Nanchang 330063,China;School of Environmental and Chemical Engineering,Nanchang Hangkong University,Nanchang 330063,China)

机构地区：[1]重金属污染物控制与资源化国家地方联合工程研究中心,南昌330063 [2]南昌航空大学环境与化学工程学院,南昌330063

出　　处：《膜科学与技术》2024年第1期45-55,共11页Membrane Science and Technology

摘　　要：聚四氟乙烯(PTFE)是一种强疏水的氟碳材料,很难用相转化成膜。本文将PTFE粉体分散在聚偏氟乙烯(PVDF)溶液中得到PTFE悬浮液,首先用干湿相转化法制得PTFE/PVDF中空纤维膜胚;然后在氮气气氛下进行部分碳化,制得部分碳化PTFE/PVDF中空纤维膜.用热重分析法、X射线光电子能谱(XPS)和扫描电镜研究了PTFE/PVDF中空纤维膜胚的碳化工艺、膜碳化前后表面元素和微观结构变化情况;最后测试了膜的亲疏水变化和油水分离性能.结果表明:PTFE/PVDF中空纤维膜胚中的PVDF在360~450℃时发生C-H断裂,PTFE保持原结构,可以得到部分碳化PTFE/PVDF中空纤维膜.经部分碳化工艺制得的中空纤维膜孔径减小,形成连续、完整的微孔结构.当PTFE含量为40%时,碳化后制得的膜接触角达到102°,疏水性提高;对10%的模拟含油废水的渗透通量达到30 L/(m^(2)·h)(跨膜压差:0.1 MPa)、分离效率达到80%,呈现出较好的油水分离性能和商业应用价值.The hydrophobic fluorocarbon material,polytetrafluoroethylene(PTFE),poses challenges in film formation through phase conversion.In this work,a PTFE suspension was obtained by dispersing PTFE powder in a polyvinylidene fluoride(PVDF)solution.Firstly,thePTFE/PVDF hollowfiber membrane embryo was prepared using a dry and wet phase conversion method.Subsequently,partial carbonization of the PTFE/PVDF hollow fiber membrane was achieved under a nitrogen atmosphere.The carbonization process of the membrane embryo,surface element and microstructure changes before and after membrane carbonization was studied using thermogravimetric analysis,X-ray photoelectron spectroscopy(XPS),and scanning electron microscopy(SEM).Finally,the changes in hydrophilicity and oil-water separation performance were evaluated for the membrane.The results revealed that PVDF within the PTFE/PVDF hollow fiber membrane embryo underwent C-H fracture at 360~450℃ whilepartially carbonizing the membrane structure.This led to a reduction in pore size and formation of a continuous and complete microporous structure within the partially carbonized hollow fiber membranes.With 40%PTFE content,after carbonization,the contact angle of the film reached 102°indicating increased hydrophobicity.Moreover,when tested with simulated oil-bearing wastewater containing 1o% oil content,these membranes exhibited an impressive permeation flux of 30 L/(m^(2)·h)(Transmembrane differential pressure 0.1 MPa)along with an efficient separation efficiency reaching up to 80%.These results highlight their promising potential for commercial applications in effective oil-water separation.

关 键 词：油水分离 非溶剂致相分离-碳化 聚四氟乙烯 中空纤维膜 

分 类 号：TQ028.4[化学工程]