Preparation of a novel antifouling mixed matrix PES membrane by embedding graphene oxide nanoplates

A novel polyethersulfone (PES) mixed matrix nanofiltration membrane containing graphene oxide (GO) nanoplates was prepared via the phase inversion method. The effect of the embedded nanosheet on the morphology and performance of the fabricated new membranes was investigated in terms of pure water flux, dye removal and fouling parameters. Scanning electron microscopy (SEM), atomic force microscopy (AFM), water contact angle and porosity measurements were employed to characterize the prepared membranes. FT-IR spectra of the graphene oxide nanoplates revealed that the hydroxyl and carboxylic acid groups are formed on the surface of the graphene oxide. The water flux from the nanocomposite membranes improved significantly after addition of graphene oxide to the casting solution, due to the higher hydrophilicity of the prepared membranes. The water contact angle measurement confirmed the increased hydrophilicity of the modified membranes. The morphology studies by SEM showed the wider finger-like pores of the GO incorporated membranes in comparison with those of the unfilled PES membrane. Evaluation of the nanofiltration performance was performed by investigating the retention of Direct Red 16. It was observed that the GO membranes have higher dye removal capacity than the unfilled PES. Fouling resistance of the membranes assessed by powder milk solution filtration revealed that 0.5 wt% GO membrane had the best antibiofouling property. In addition, the results showed that the 0.5 wt% GO membrane had the highest mean pore radius, porosity, and water flux. The prepared GO nanocomposite membrane showed noteworthy reusability during filtration.