Cost-effective one-pot surface modified method to engineer a green superhydrophobic sponge for efficient oil/water mixtures as well as emulsions separation

摘要

Herein, a superhydrophobic and superoleophilic melamine sponge is fabricated by immersing the original sponges in ethanol solution containing tannin acid and n-octadecylamine. Meanwhile, the reagents are more economical and eco-friendly than commonly superhydrophobic modified materials such as dopamine, graphene, and 1-dodecanethiol. By integrating the high porosity, superior elasticity, and mechanical stability of the raw sponge with the low surface energy of n-octadecylamine and their nanometer scale roughness, the modified sponge not only possesses superhydrophobic surface with the water contact angle of 154.8 degrees but also exhibits excellent adsorption performance (absorption weight ranging from 70 to 148 times of its own) and extraordinary recyclability. The treated sponge also have superb separation efficiency for oil/water mixtures and emulsions, 99.95% and 99.57%, respectively. Besides, the simple processing is easy to scale up. All the merits manifest that this superhydrophobic sponge is the desired candidate for handing oil pollution in the sea.