PEI/SA/Cu三元体系改性荷正电纳滤膜及其脱盐性能  

PEI/SA/Cu ternary system modified positively charged nanofiltration membrane and its desalting performance

作　　者：马晓华[1] 梁晓康 许振良[1] MA Xiaohua;LIANG Xiaokang;XU Zhenliang(Membrane Science and Engineering R&D Lab,School of Chemical Engineering,East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]华东理工大学,化工学院,化学工程研究所,膜科学与工程研发中心,上海200237

出　　处：《膜科学与技术》2024年第4期8-16,共9页Membrane Science and Technology

基　　金：国家重点研发计划项目(2021YFB3801103)。

摘　　要：通过将海藻酸钠(SA)与聚乙烯亚胺(PEI)共混作为二次界面聚合反应的水相溶液,SA与PEI强相互作用使SA嵌入到聚酰胺层中,从而提高膜的致密性.随后通过Cu^(2+)与SA结合提高膜表面荷正电性,提高膜对多价阳离子的截留性能.对比研究了SA和Cu^(2+)浓度对复合膜物化性质、表面形貌及分离性能的影响.结果表明,荷正电纳滤膜的最佳制备条件为:SA质量分数为0.01%,Cu^(2+)浓度为25 mmol/L,所对应的PS/Cu-3复合膜亲水性提高.与Control-PEI膜相比,其通量提高了257%,为(40.0±0.8)L/(m^(2)·h),对MgCl2的截留率从92.0%提升至97.1%,且具有良好的耐压性和稳定性.In this paper,sodium alginate(SA)and polyethylenimine(PEI)were blended as aqueous solution for secondary interfacial polymerization(SIP)reaction.The strong interaction between PEI and SA made SA embed into polyamide(PA)layer,thus improving the density of the membrane.Subsequently,the surface positive charge was improved through the complexation of Cu^(2+)with SA and PEI,and the retention of polyvalent cations was improved.The effects of SA and Cu^(2+)concentrations on physicochemical properties,surface morphology and separation performance of the composite membranes were studied.The results showed that the optimal membrane preparation conditions were as follows:SA concentration was 0.01%,Cu^(2+)concentration was 25 mmol/L.The corresponding PS/Cu-3 composite membrane has enhanced hydrophilicity and density,and decreased pore size.Compared with Control-PEI membrane,its flux is increased by 257%to(40.0±0.8)L/(m^(2)·h),and the rejection of MgCl_(2) is increased from 92.0%to 97.1%,and it has good pressure resistance and stability.

关 键 词：PEI/SA/Cu三元体系改性 荷正电 纳滤膜 脱盐性能 

分 类 号：TQ028.8[化学工程]