Development and Characterisation of a Nanocomposite Membrane Using Polyethersulphone and Graphene Oxide-Magnetite Nanoparticles for Rejection of Chromium Hexavalent Ions from Tannery Wastewater

Polyethersulphone (PES) polymer blended with Graphene Oxide (GO) and magnetite ( nano-composite was synthesized using an immersion precipitation process for the filtration of chromium hexavalent ions from leather processing waste water. PES is a synthetic polymer with good chemical resistance, wide pH range (2-13) as well as good mechanical and thermal properties. However, it is hydrophobic and prone to fouling hence its limitations in aqueous separation processes. In order to improve hydrophilicity, porosity, permeability and strength properties of the polymeric membrane, GO was synthesized from coal via a modified Hummers Method and then blended with anhydrous ferrous chloride to form Graphene oxide/ magnetite () hybrid nano-particles. To assess the performance of the membrane pure water flux, Equilibrium Water Content (EWC) and tensile strength test was measured. Structural analysis involved porosity measurement. The filtration efficiency of the membranes was found by testing the waste water for chromium ion concentration before and after filtration. It was established that both the physical properties and chromium ion rejection improved with increase in polymer concentration and addition of  hybrid nano-particles.