PA/PEG交联共聚反渗透膜的制备及耐污染性能

Fabrication and anti-fouling performance of PA/PEG cross-linked copolymer reverse osmosis membranes

以聚丙烯腈(PAN)超滤膜为基底,在均苯三甲酰氯(TMC)和间苯二胺(MPD)界面聚合反应过程中引入聚乙二醇(PEG),制备聚酰胺(PA)/PEG反渗透复合膜。利用傅里叶红外光谱(FTIR)、X射线光电子能谱(XPS)、场发射扫描电镜(FE-SEM)和原子力显微镜(AFM)等对膜的结构和物化性质进行了表征。考察了PEG分子量、PEG加入量、热处理温度及时间对膜反渗透性能的影响,并系统考察了膜对十二烷基硫酸钠(SDS)、十二烷基三甲基溴化铵(DTAB)以及牛血清蛋白(BSA)三种不同荷电性典型污染物的耐受性能。实验结果表明,相比于未改性的PA反渗透膜,PEG交联共聚反渗透膜的盐截留率和通量恢复率均有所提高。其中PA/PEG1000-0.1膜渗透通量为3.96kg/(m^(2)∙h),NaCl表观截留率为97.5%,并且对于SDS、DTAB和BSA都表现出较高的耐污染性,其中,SDS污染清洗后膜的通量恢复率可达89.4%。

Polyethylene glycol(PEG)modified polyamide(PA)reverse osmosis(RO)composite membranes were fabricated via an interfacial polymerization of trimesoyl chloride(TMC)and m-phenylenediamine(MPD)with PEG using the polyacrylonitrile(PAN)ultrafiltration membranes as the supports.Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),field emission scanning electron microscope(FE-SEM)and atomic force microscope(AFM)were used to characterize the textural and physicochemical properties of the membranes.The effects of PEG molecular weight,PEG content,heat treatment temperature and time on RO performances of the membranes were investigated.Moreover,three typical pollutants,sodium dodecyl sulfate(SDS),dodecyl trimethyl ammonium bromide(DTAB)and bovine serum albumin(BSA)were used to examine fouling resistance of the membranes.Compared with the unmodified PA membranes,the salt rejection and flux recovery of PEG cross-linked PA membranes were improved.The PA/PEG1000-0.1 membranes delivered an observed NaCl rejection of 97.5%and a water flux up to 3.96kg/(m^(2)∙h).Moreover,the membrane exhibited high fouling resistance to SDS,DTAB and BSA with a flux recovery rate of 89.4%after fouling of SDS.