High performance polyamide composite nanofiltration membranes via reverse interfacial polymerization with the synergistic interaction of gelatin interlayer and trimesoyl chloride

Abstract

A novel polyamide (PA) thin film nanofibrous composite (TFNC) nanofiltration membrane consisted of electrospun polyacrylonitrile (PAN) nanofibrous substrate, gelatin interlayer and polyamide barrier layer was fabricated by reverse interfacial polymerization (IP-R). The prepared PA separating layer was ultrathin, crumpled, and defect-free, which was benefited from the synergistic interaction of the gelatin nanofibrous interlayer and trimesoyl chloride (TMC). The ultrafine gelatin nanofibrous interlayer could absorb and react with TMC in n-hexane, regulating the rising speed of the n-hexane under aqueous phase for the formation of the polyamide layer. Significantly, the nanofiltration performance of TFNC membranes was tuned by changing the deposition amount of gelatin in the nanofibrous interlayer. The flux of the optimized TFNC membrane was up to 135.6 L m−2 h−1 (about 98.1% Na2SO4 rejection) under 0.5 MPa, which was nearly triple fold of that of the membrane prepared at the same condition by interfacial polymerization (IP–F). This work may provide an efficient and facile approach to fabricate high performance nanofiltration membranes with unique structures.