Development of graphene oxide (GO)/multi-walled carbon nanotubes (MWCNTs) nanocomposite conductive membranes for electrically enhanced fouling mitigation

In this study, we fabricated electrically conductive membranes using graphene oxide (GO) and multi-walled carbon nanotubes (MWCNTs) via the blending phase inversion method. The effects of the membrane polymer: solvent and the GO: MWCNTs weight ratios on the electrical conductivity of membrane were investigated. It was discovered that batch M10 membranes exhibited moderately high electrical conductivity due to incorporation of carbon nanomaterials forming continuous electron paths across the membrane matrix. Using this optimized batch of membranes, performance test was conducted on the palm oil mill effluent (POME). In general, the flux decline was reduced with the continuous and intermittent electric fields. The presence of an electric field exerted a stronger repulsion force to repel the foulant and thus reduced the blockage of the membrane surfaces. As compared to the absence of electric field, M10(c)-5, M10(c)-10, and M10(c)-20 had improved the normalized flux by 108.14%, 90.54%, and 89.69%, respectively, with the continuous electric field of 300 V/cm. M10(c)-5 exhibited the optimal extent of fouling mitigation, as attributed to the enhancement of membrane electrical conductivity without compromising other membrane characteristics. Overall, this study showed that, with the right membrane formulation, a good conductive membrane with electrically-enhanced antifouling properties can be fabricated.