Preparation and characterization of PSF/PEI/CaCO nanocomposite membranes for oil/water separation.

Ultrafiltration (UF) is one of the significant advanced processes for oily wastewater treatment due to its clear advantages, for instance, ease in operation and efficient separation. The main drawback of these processes is the fouling problem and many researchers' effort on fabrication of high-performance membranes with higher hydrophilicity and antifouling properties. In this study, flat-sheet polysulfone (PSF)/polyethylenimine (PEI)/CaCO nanocomposite membranes were prepared by phase inversion method for oil/water emulsion separation. Structural properties of membranes were characterized by SEM, FT-IR, contact angle, tensile strength, and atomic force microscopy analysis. Increasing the CaCO nanoparticle loading exhibited the increased the water flux and BSA rejection. PSF/PEI/10 wt% CaCO nanocomposite membranes have 145 L/m h water flux at 2 bar with a contact angle of 84° and with 92% BSA rejection. All prepared CaCO nanocomposite membranes reached similar oil rejections at above 90%. Besides the higher water flux and oil removal efficiencies, 10 wt% of CaCO nanoparticle-blended PSF membranes has notable antifouling capacity with the highest flux recovery ratio (FRR) and lowest flux decay ratio (DR) values. The results showed that there is a great potential to use PSF/PEI/CaCO nanocomposite membranes for the treatment of oil water emulsions with higher permeability and antifouling capacity.