In situ generated micro-bubbles enhanced membrane antifouling for separation of oil-in-water emulsion

Abstract Membrane fouling has been considered as the greatest challenge for membrane separation especially in oil/water separation process. Novel strategies for reducing membrane fouling are highly important for membrane separation. In this study, a novel membrane antifouling method in oil/water separation was proposed through in situ generated micro-bubbles. The fouling reduced process was realized by combination of membrane separation and catalytic reaction. Oxygen micro-bubbles were in situ generated by the decomposition of hydrogen peroxide (H2O2) under the catalysis of manganese oxide nanoparticles, which were loaded on the surface of carbonized PAN (cPAN) nanofibrous membrane. In situ generated micro-bubbles significantly inhibited the surface deposition of rejected oils through hydrophobic interaction between micro-bubbles and oils. Membrane permeability was significantly reduced to 909 ± 286 Lm−2h−1bar−1 (3% of its initial data) after 65 min of continuous oil-in-water separation. However, it remains as high as 14755 ± 1930 Lm−2h−1bar−1 (67.6% of initial data) with the presence of H2O2, which was 16.2 times higher. The current study presents a potential approach to achieve continuous oil/water emulsion separation with reduced membrane fouling and advance the practical application of membranes for oil/water separation.