Influence of the polyacrylonitrile proportion on the fabricated UF blend membranes’ performance for humic acid removal

Asymmetric blend membranes of polyethersulfone (PES)/polyacrylonitrile (PAN) were prepared and developed for ultrafiltration applications. The membranes were prepared by dissolving two polymers in N-methyl-2-pyrrolidone (NMP) as a solvent with diethylene glycol (DEG) and polyvinylpyrrolidone (PVP) as non-solvent and pore former, respectively. The produced membranes were characterized by scanning electron microscopy (SEM) and fourier transform infrared (FTIR) spectroscopy, and the hydrophilicity of membranes was tested by contact angle measurements. The performance of prepared membranes was carried out by an ultrafiltration testing unit, where the efficiency of membranes was determined according to the humic acid separation and treated water permeate flux. The results indicated that using 1 wt.% of PAN in polymer mixture provided a blending membrane with high mechanical properties and high performance; the humic acid rejection reached 92.47% with treated water permeate flux 70 l/m(2).h at feed pressure 6 bar.