Graphene oxide/chitosan doped polysulfone membrane for the treatment of industrial wastewater

Abstract

AbstractRapid urbanization and industrialization have created tremendous stress on fresh water sources. Moreover, discharge of industrial wastewater has left public health and environment under high potential risks. In this paper, chitosan-functionalized graphene oxide (GO-CH) was synthesized and incorporated into polysulfone (Psf) ultrafiltration membranes. The concentration of the nanocomposite and the ratio of GO to CH in the nanocomposite were varied to produce different GO-CH doped polysulfone membranes. The effect of GO-CH addition on the morphology and membrane performance was studied through water contact angle, scanning electron microscopy, atomic force microscopy, porosity, pore size, and permeation measurements as well as rejection and antifouling tests, while produced GO-CH nanocomposite was characterized using FTIR and XRD analyses. The GO-CH/Psf membrane exhibited higher water flux, bovine serum albumin (BSA) rejection rate, and water flux recovery ratio, and lower BSA solution flux attenuation rate than pristine Psf membrane. GO-CH/Psf membrane containing 0.085 wt% nanocomposite with GO to CH ratio of 1 to 0.01 had an improved permeate flux of 136%. Maintaining the same GO-CH composition of 0.085 wt% and changing GO to CH ratio to 1:1 resulted in better hydrophilicity (contact angle 68°) and increased reversible fouling from 23 to 33%. The best membrane was further tested with real industrial wastewater obtained from a GTL plant in Qatar showed 28% improvement in COD removal.