Fabrication of robust superhydrophobic-superoleophilic mesh for oil-water separation under harsh environment

Abstract

Frequent oil spillage at sea and waste oily water draining cause severe harms to the environment and economy. Although various extreme wettable materials are designed to achieve oil-water separation, there are still limitations such as expensive materials, fluorine-containing reagents, and poor robustness of oil-water separating materials. Here, we resolved the above problems by proposing a simple and low-cost sandblasting plating method with Ni, P, and 1-octadecanethiol modification to manufacture a robust superhydrophobic stainless steel mesh for separating oily water under harsh environments. The mesh can achieve the light and heavy oily water with outstanding separating efficiency and high purity. It can be also used to separate HCl solution, NaOH solution, and NaCl solution-oil, with the separating efficiency larger than 95%. Moreover, the mesh still was superhydrophobic and had outstanding oil-water separating efficiency after sandpaper abrasion, tape stripping, simulated seawater corrosion, and natural environment corrosion tests. Therefore, the robust superhydrophobic stainless steel mesh proposed in this work can very efficiently separate oily water in harsh environments.