GO–Polymer Modified Anion Exchange Membranes for Antifouling

Organic fouling was one of key issues limiting the application of electrodialysis in the treatment of industrial wastewater, which results in degradation of membranes and high energy consumption. In this study, a novel graphene oxide (GO)–polymer modified anion exchange membrane (AEM) for antiorganic fouling was first developed by layer-by-layer interfacial polymerization (IP). The surface of AEM was alternately contacted with GO and tannic acid (TA) aqueous as the water phase and an n-hexane solution of trimesoyl chloride (TMC) as the organic phase; thus, a multilayer GO–polymer structure was fabricated on the surface of AEM. Results showed that the aqueous phase was preferred to be the final treatment of layer-by-layer interfacial polymerization, which was more conducive to enhancing hydrophilicity and negative charge density of the membrane surface. Compared with TA-TMC modified AEM, the introduction of GO nanosheets with carboxyl groups into aqueous solution significantly increased the negative charge density of the membrane surface and reduced membrane resistance. The desalination rate of (GOTA-TMC)_1.5 was mostly close to that of pristine AEM without fouling, exhibiting significant antifouling performance and good stability. The study provides promising insights into the modification of ion exchange membranes with functional materials and a polymer composite layer.