Construction of high selectivity and antifouling nanofiltration membrane via incorporating macrocyclic molecules into active layer

Abstract

We demonstrated the fabrication of a loose, hydrophilic and antibacterial nanofiltration (NF) membrane with high mono/divalent salt selectivity and antifouling ability. Macrocyclic molecule, primary amination Noria (PANoria), was synthesized firstly. Then the PANoria was taken as a novel aqueous phase monomer alone for thin film composite (TFC) membrane preparation via interfacial polymerization (IP) with trimesoyl chloride (TMC). Consequently, the well-defined pore structure, hydrophilic and antibacterial groups of PANoria could be effectively introduced into active layer of NF membranes. The hydrophilicity, zeta potential and pore size distribution of membranes could be altered by regulating the PANoria concentration or IP reaction time. When the PANoria concentration was 2.0 wt% and IP reaction time was 20 min, the PANoria membranes exhibited outstanding NaCl/Na2SO4 selectivity and the water permeance was 14.5 ± 0.5 L m−2 h−1 bar−1. Furthermore, the flux recovery ratio was more than 95% in the BSA/HA filtration test and the E.coli bacteria killing ratio was more than 92% in the bacteria contact experiment. Therefore, this work provided a viable strategy for fabricating NF membrane with high selectivity and outstanding antifouling ability.