新型高通量复合纳滤膜的制备及其性能研究

Study on the Preparation of Novel Composite Nanofiltration Membrane with High Flux and Its Performance

以聚乙烯亚胺(PEI)和单宁酸(TA)为水相单体、均苯三甲酰氯(TMC)为油相单体,通过界面聚合制备了复合纳滤膜,并对膜性能进行了表征和评价测试。结果表明,水相溶液TA、PEI的质量分数分别为0.3%、0.2%,水相pH为12,油相溶液TMC的质量浓度为0.2 g/L,反应时间为1 min,在60℃下烘干成膜为优化制备条件。此复合膜在温度为25℃、压力为0.5 MPa下得到的对4种无机盐截留顺序为Na2SO4>MgSO4>MgCl2>NaCl,水通量MgCl2>NaCl>Na2SO4>MgSO4。该纳滤膜具有良好的SO4^2-和Cl^-的分离效果。同时,该纳滤膜具有良好的耐污染性能,对腐殖酸和牛血清蛋白的24 h抗污染测试,水通量仍达到初始水通量的84.2%以上。

The composite nanofiltration membrane was prepared by interfacial polymerization with polyethyleneimine(PEI)and tannic acid(TA)as monomer in aqueous phase,and trimesoyl chloride(TMC)as monomer in oil phase.The membrane properties was characterized and tested.The results showed that,the optimal preparation conditions was that the mass fractions of TA and PEI in the aqueous solution was 0.3%and 0.2%,the pH of the aqueous phase was 12,the mass concentration of the TMC in the oil phase was 0.2 g/L,the reaction time was 1 min and the curing temperature was 60℃.The rejection sequence of four inorganic salts obtained at 25℃and 0.5 MPa was Na2SO4>MgSO4>MgCl2>NaCl and the water flux sequence was MgCl2>NaCl>Na2SO4>MgSO4.The nanofiltration membrane had good separation effect of SO4^2-and Cl^-.Meanwhile,the nanofiltration membrane also had good anti-fouling performance.For the 24 h anti-fouling test of humic acid(HA)and bovine serum albumin(BSA),the water flux reached more than 84.2%of the initial water flux.