Nanofiltration is a membrane-based separation process that has been used widely in the separation and purification fields for various applications such as dye desalting, applications of water softening, pharmaceuticals and wastewater treatment. In this research, polyethersulfone (PES), polyethylene glycol (PEG), Pluronic F108 and silver nanoparticles (AgNPs) nanofiltration membrane was prepared using casting solution technique with N-methyl-2-pyrrolidone (NMP) was used as a solvent. The effects of Pluronic F108 and silver nanoparticles (AgNPs) concentrations in the casting solutions on the membrane performance/properties were also studied. The membrane pure water permeation (PWP) and salt rejection tests were carried out for membrane performance analysis. Scanning electron microscopy (SEM) was used for the membrane morphology characterization. Fourier transform infrared spectroscopy was utilized to identify functional groups in the membrane. Membrane with 2.0 wt.% of Pluronic F108 and 0.05 wt.% of AgNPs showed the best performances for both PWP (40.89 L/m2h) as well as permeation flux of salts solution of NaCl (43.95 L/m2h), Na2SO4 (21.16 L/m2h), MgCl2 (26.46 L/m2h) and MgSO4 (20.41 L/m2h). All fabricated membranes with different formulation of dope composition obtained high salts rejection in the range of 79% to 91%. SEM images showed addition of AgNPs has improved fabricated membrane morphology with higher pore density and larger macro-void structure.

Recently, dyes are generally used in various industries and release of these dyes into streams will pose a serious threat to the environment. In this research, a nanofiltration membrane was fabricated via phase inversion as it is one of the most convenient methods for membrane fabrication. It is used in removing dyes by using pluronic as a surfactant and chitosan as an additive. By varying the concentration of pluronic as a surfactant at 1 wt%, 2 wt%, and 3 wt%, and a constant amount of chitosan as an additive, three newly dope solutions were formulated. The fabricated membranes were analyzed by evaluating the membrane in terms of pure water permeation (PWP), permeation flux, salts rejection and dyes rejection. The introduction of pluronic as a surfactant and chitosan as an additive to the nanofiltration membrane produced high PWP and presented high salts rejection and dyes removal. Generally, high dyes rejections were achieved by M3 which contained high weight percentage (wt%) of pluronic as it showed highest percentage rejection for acid red, methyl blue and reactive black 5. The functional groups of the membranes were characterized and verified by using Fourier transform infrared spectroscopy (FTIR).