Highly Efficient Amorphous Carbon Sphere-Based Superhydrophobic\nand Superoleophilic Sponges for Oil/Water Separation

Abstract

In this experimental study, a commercially\navailable polyurethane\n(PU) sponge coated with amorphous carbon spheres (ACSs) is investigated\nfor oil/water separation. The ACSs synthesized using chemical vapor\ndeposition are embedded in the PU sponge by a simple dip-coating method.\nThe superhydrophobic ACS-PU sponge exhibits a water contact angle\n(WCA) of 156.2 ± 1° and a sliding angle <5°. The\nprepared sponge exhibits high absorption capacity, removal of oil\nspills from water, and demulsification of an oil-in-water emulsion.\nAbsorption capacities of 32–68 times the ACS-PU sponge weight\nwere obtained for different organic solvents and oils. It was found\nthat the prepared ACS-PU sponge can effectively absorb oils under\nboth static and turbulent conditions. Compared with the reported studies\non the loading of different carbon materials in sponges for oil/water\nseparation, ACSs in PU have a low loading percentage of ∼7\nwt % and better absorption recyclability. The method proposes a simple\nand cost-effective preparation technique of highly hydrophobic and\noleophilic ACS-PU sponges for effective oil/water separation.