Hydrophobic Phase Inverted Polyethersulfone Mixed Matrix Membrane for Water-in-Oil Emulsion Separation

The limited access to clean water sources and the severe consequences of oil spills on the environment are of significant concern. Membrane technology showed superior performance to the other conventional techniques due to its higher performance, lower cost, ability to separate emulsions, and being more environmentally friendly. Emulsified water/oil emulsions are highly stable and have a small droplet size, hence are more challenging to separate than water/oil mixtures. Herein, hydrophobic iron oxide-oleylamine (Fe-Ol) nanomaterial was prepared and used to fabricate polyethersulfone (PES) mixed matrix membranes (MMMs) using non-solvent induced phase separation (NIPS). A similar procedure was used to fabricate pristine PES. The performance of the membranes in emulsion separation was tested using a dead-end vacuum filtration setup and a 1 vol.% water-in-n-hexane surfactant stabilized emulsion. The use of the hydrophobic Fe-Ol nanomaterial enhanced the separation efficiency of the membranes. The 1.5 wt.% PES/Fe-Ol MMM exhibited a 97.4% separation efficiency and a high filtrate flux of 1020 L/m2h (LMH), hence, showing great potential in the application of water-in-oil separation.