Robust Superhydrophobic Sepiolite-Coated Polyurethane Sponge for Highly Efficient and Recyclable Oil Absorption

With the rapid increase of oil production and offshore transportation, the probability of accidental oil leakage is rising. Utilization of superhydrophobic materials constitutes an effective method to solve oil pollution on the water surface. In this study, a modified superhydrophobic sepiolite (SEP) layer was loaded onto the skeleton surface of three-dimensional (3D) porous polyurethane (PU) sponges through a one-step ultrasonic dip-coating process. The as-prepared superhydrophobic sponges can rapidly and selectively absorb multiple oils and nonpolar solvents that are more than 29 times the weight of the sponge, while completely repelling water. In addition, the as-prepared composite material could be reused for oilwater separation for more than 10 times with a high separation efficiency of over 99.45%. The composite material also exhibited robust superhydrophobicity in corrosive liquids and hot water. The results of this research may provide a promising absorbent material that might be used to effectively remove oil spills from the surface of water.