(529g) Graphene Oxide-Polysulfone Mixed Matrix Membranes: Effect of Graphene Functionalization and Loading on Oil-Water Separation Performance and Membrane Fouling

Microfiltration and ultrafiltration polymeric membranes plays significant role in water treatment and water desalination pre-treatment applications. The performance of these membranes is characterized by their flux, percentage rejection of impurities and resistance to inorganic, organic, and biofouling. In this presentation, the performance of polysulfone (PS) ultrafiltration (UF) membranes is enhanced by incorporating small fractions (< 0.8 wt.%) of graphene oxide functionalized with amine (a-GO) and carboxylic (cGO) groups. Pure PS and PS mixed matrix membranes (MMM) containing a-GO and c-GO are fabricated by the phase inversion method and membrane hydrophilicity, morphology, porosity, and mechanical properties are investigated using contact angle measurements, SEM, AFM, and dynamic mechanical analysis. The impacts of GO functionalization on the separation of oil-water emulsion and protein (bovine serum albumin (BSA)) fouling were investigated. The hydrophilicity of the membrane increased with increasing the concentration of the functionalized GO, regardless of the functionalization type. On the other hand, the flux and rejection was increased with GO loading up to an optimum loading of ~ 0.2 wt.% and then declined with higher concentrations. Moreover, the addition of f-GO leads to not only enhanced permeability and rejection but also significant improvement in the mechanical properties and durability compared to pristine PS membrane. The antifouling testing of the fabricated membranes was assessed by the filtration of bovine serum albumin (BSA) solution and the f-GO membranes demonstrated better fouling resistances compared to pristine PS membrane. Our results indicates that f-GO membranes have outstanding potential in the field of water treatment as they offer significant enhancement in the performance, mechanical properties and antifouling characteristics at very low concentration that does not affect the theological properties of the PS-f-GO formulation and therefore requires no alteration to the current commercial fabrication process.