Synthesis and application of graphene oxide and sulfonated graphene oxide nanoparticles for using in nanofiltration membranes polyether sulfone

In this study, graphene oxide (GO) was synthesized through the improved Hummer method and sulfonated graphene oxide nanoparticles (s-GO) were prepared by effective sulfonation reaction. To evaluate the effectiveness of nanofiltration membranes, the membranes were prepared based on the mixing of polyether sulfone with graphene oxide (GO) and sulfonated graphene oxide nanoparticles. Synthesis of GO and s-GO nanoparticles was structurally evaluated using FT-IR and Raman spectroscopy. Nanocomposite membrane containing nanoparticles were fabricated via phase inversion method and their performance was evaluated using membrane evaluation tests. Surface, cross-section morphology and membrane structure were observed by FE-SEM. The wettability of the membrane surface was determined by the test of contact angle, membrane porosity, water absorption and average membrane pore radius. Nanofiltration membrane performance was evaluated by measuring pure water flux, dye removal ability, desalination from aqueous solution, removal of heavy metals, fouling rate and flux recovery ratio. It seems, practically very hydrophilic -OSO3H groups located on GO surfaces can increase the hydrophilicity of the membrane and improve its anti-fouling properties in the final membrane. Fouling test for graphene sulfone-containing membranes showed better results.