A loose polyamide nanofiltration membrane prepared by polyether amine interfacial polymerization for dye desalination

It is crucial for fractionating dye/salt mixture in dyeing wastewater treatment. Herein, a polyamide nanofiltration (NF) membrane (PEA-TMC) for high efficient dye desalination was prepared through polyether amine (PEA) and trimesoyl chloride interfacial polymerization. Due to the large molecular size and hydrophilicity of PEA, the resulting NF membrane possessed a relatively loose membrane structure and good hydrophilicity, which improved membrane water flux and dye desalination performance. The influences of PEA concentration and reaction time on the NF performance were systematically investigated. Under the optimal conditions, the membrane exhibited a high water flux of 66.4 L m -2 h −1 at low operating pressure (0.4 MPa), and showed a high methyl blue rejection (95.4%) and low NaCl rejection (16.4%) when nanofiltrated methyl blue/ NaCl mixture solution. Moreover, PEA-TMC membrane exhibited good stability in continuous operation and antifouling performance. These results disclosed the promising applications of PEA-TMC membrane in dye/salt separation process.