(711d) Fabrication of Newly Developed Nanofiltration (NF) Composite Membranes Via IP for Aqueous Dye Removal

Taking into account of energy consumption and environment issues, nanofiltration emerges as a process substituting for the conventional separation processes and purification technique such as distillation for their high energy consumption in separating mixtures on molecular level. Among all of the configuration of nanofiltration modules, hollow fiber nanofitration module has higher the obvious advantages of higher packing density, less pre-treatment and maintenance, which has motivate many researchers’ interests. In this study, thin-film-composite (TFC) nanofiltration (NF) membranes were newly developed through interfacial polymerization (IP) on the lumen side of hollow fiber support membranes by exploring novel combination of reacting monomers and the optimum conditions of fabrications and further utilized to remove typical dyes in aqueous solutions at different conditions. Based on the different combinations of reacting monomers, the molecular weight cut off (MWCO) of NF membranes in the hollow fiber module can be adjusted to be around 300.0 g mol^-1 with the high pure water permeability of 3.1 L m^-2 h^-1 bar^-1 at 3.0 bar. The hollow fiber NF membranes demonstrated different rejections for different salts in the order of R(Na₂SO₄)>R(MgSO₄)>R(NaCl)>R(MgCl₂) and high pressure resistance. For both of Safranin O and Aniline blue dyes, the rejection can be higher than 90% under testing conditions, and the excellent performance of NF membranes to remove dyes from waste water can be maintained in a wide range of pH values although the best performance was obtained at the pH value of 11. Therefore, the novel NF membranes are promising for removing crucial dyes as the next-generation technology for industrial wastewater treatment.