Biodiesel produced from waste cooking oils was purified by use of polyethersulfone-co-TiO2 nanocomposite membranes. The membranes were prepared by solution casting technique through phase inversion method. Titanium dioxide nanoparticles were used as inorganic filler additive in membrane fabricating. The effect of nanoparticle concentration in the casting solution on the physico-chemical characteristics, morphology and performance of prepared membranes was studied. SEM, AFM and XRD analyses were carried out for the characterization of membrane. The results showed uniform nanoparticle distribution in the membranes matrix. XRD results also indicated a crystalline structure for the membranes. Membrane surface roughness was decreased sharply by increase of nanoparticle concentration up to 0.05%wt in membrane matrix and then increased slightly. Membrane flux, rejection, water content, porosity and membrane mechanical strength were enhanced initially by increase of nanoparticles concentration up to 0.05%wt and then decreased by more increase of nanoparticles content ratio. The nanocomposite membrane containing 0.05 wt% TiO2 showed more appropriate performance compared to others.
