Preparation of poly(2,4,6‐triaminopyrimidine‐TMC)/P84 composite nanofiltration membrane with enhanced chlorine resistance and solvent resistance

Abstract

AbstractBACKGROUNDNanofiltration membrane has attracted great study interest because of its high permselectivity and low operating cost. However, most commercial nanofiltration membranes are still not applicable for chemical separation processes due to their low resistance to organic solvent and chlorination.RESULTS2,4,6‐triaminopyrimidine (TAPI) was employed as an aqueous phase monomer to prepare poly (2,4,6‐triaminopyrimidine‐TMC) composite nanofiltration membrane with interfacial polymerization. Polyimide (P84) ultrafiltration (UF) membrane was crosslinked with TAPI and used as the supporting membrane. The composite membrane showed high rejection (91.4%) of Na2SO4 and a high flux (7.3 L m−2 h−1) at 0.3 MPa and ambient temperature. The membrane also showed high stability during 120 h immersion in N,N‐dimethylacetamide (DMAc) and acetone. The performance of membrane immersed in 200 ppm NaClO solution did not decline over 96 h.CONCLUSIONTAPI with reactive amino group can be used as aqueous phase monomer to prepare poly (2,4,6‐triaminopyrimidine‐TMC) composite nanofiltration membrane with high permselectivity. The pyrimidine ring of TAPI endows the functional layer with excellent chlorine resistance while the crosslinking of P84 membrane with TAPI significantly improves the solvent resistance. © 2018 Society of Chemical Industry