相转化法制备PES/PAES-C/PEI紧密超滤膜及其染料/盐分离性能OA

A casting solution was initially prepared by blending polyethersulfone(PES)with carboxyl group-containing polyaryl ether sulfone polymer(PAES-C),and a polyethyleneimine(PEI)solution with a mass fraction of 1％was used as the coagulation bath.Owing to the interactions between the abundant amine groups of PEI and the carboxyl groups on the PAES-C chains,a hydrophilic and compact selective layer was constructed on the membrane surface and resulted the generation of a tight ultrafiltration membrane with high permeability,dye rejection,and excellent antifouling properties.The morphology,surface chemical composition,and hydrophilicity of membrane were characterized by scanning electron microscopy,Fourier transform infrared spectroscopy,and water contact angle measurements,respectively.The effects of the solid content of the casting solution on the pure water flux,Congo red dye flux,and rejection performance of the PES/PAES-C/PEI membranes were systematically investigated.The separation performance of the membranes toward different dyes under various salt concentrations and dye concentrations was evaluated,along with their antifouling behavior and long-term operational stability.The results demonstrated that the prepared PES/PAES-C/PEI membrane exhibited a high permeation flux of 230.6 L/(m2·h)while maintained rejection rates more than 99％for Congo red,Direct Red 23,and Coomassie Brilliant Blue.However,alow rejection rate only at 15.75％was observed for Na2SO4.Moreover,the membrane showed outstanding antifouling performance and operational stability in bovine serum albumin(BSA)fouling tests and 24 h continuous filtration experiments,indicating its great potentiality for the separation of high-salinity dye wastewater.