Durable superhydrophobic Fe3O4@C/PVDF/PU sponge for efficient separation of surfactant-stabilized organic solvent/water emulsions

Abstract

Developing superhydrophobic material with good chemical stability, non-toxic and low-cost for effectively handling oil spill incidents, chemical leakages and industrial oily wastewater has become an urgent need. In this work, superhydrophobic Fe₃O₄@C microspheres have been successfully anchored on polyurethane (PU) sponge skeleton surface with polyvinylidene fluoride (PVDF) as intermediate layer. The superhydrophobic Fe₃O₄@C/PVDF/PU sponge possesses outstanding superhydrophobic performance with water contact angle (WCA) of 156.5° and sliding angle (SA) of 6°. Meanwhile, the Fe₃O₄@C/PVDF/PU sponge shows excellent chemical, thermal and mechanical stabilities under harsh conditions, high separation efficiencies for surfactant-stabilized organic solvent/water emulsions (more than 99.6% for both O/W and W/O emulsions) and preferable recyclability (more than 15 cycles). The comprehensive performances of the Fe₃O₄@C/PVDF/PU sponge make it a promising candidate for the treatment of industrial oily wastewater.