Graphene oxide decorated copper nanoparticles embedded polysulfone nanocomposite membrane: Anti-bacterial, organo-bio fouling evaluation in pharmaceutical wastewater treatment via MBR

Abstract

This study investigates the impact of incorporating graphene oxide (GO) nanosheets and copper nanoparticles decorated reduced graphene oxide (Cu/rGO) on the performance of polysulfone (PSf) membranes in a membrane bioreactor (MBR) system. The characterization of the synthesized nanomaterials confirmed superior antibacterial activity of Cu/rGO compared to GO. Compared to the neat PSf membrane, the prepared nanocomposite membranes exhibited enhanced antibacterial, hydrophilic properties, pure water flux and porosity. Furthermore, the morphological analysis suggested that the GO and Cu/rGO nanohybrids exhibited outstanding interface compatibility and less release (<7%) during 20 days of immersion. During the treatment of the pharmaceutical wastewater in bench scale MBR system, total fouling ratio (TFR) was decreased from 80.24 % for neat PSf membrane to 74.37 % and 67.85 % for PSf-GO and PSf-Cu/rGO membranes, respectively. Notably, the flux recovery ratio (FRR) of the optimized PSf-Cu/rGO and PSf-GO nanocomposite membranes significantly increased 1.44 and 1.25 folds compared to the neat PSf membrane, respectively. The analysis of extracellular polymeric substances indicated an outstanding reduction in protein and carbohydrate concentrations in the cake layer in the presence of nanohybrids, confirming the membranes’ ability to mitigate organic and bio-fouling. These findings suggest GO and Cu/rGO nanohybrids enhance PSf membranes performance in MBR applications.