Simple anodic oxidation method for the preparation of superhydrophobic stainless-steel mesh for oil-water separation

Nowadays, all kinds of oil products have become an important pillar of human economic development. The generation and leakage of oily wastewater in the process of oil collection, processing and transportation will have a bad impact on human and nature. Oil-water separation has become a research hotspot. Materials with special wettability have attracted great attention. In this work, 316L stainless-steel mesh with micro-nano composite structure on the surface was obtained by a simple anodic oxidation method. After perfluorooctanoic acid modification, superhydrophobicity was obtained, which showed reverse affinity to oil and water, and could realize the separation and collection of oil in oil-water mixture. The separation efficiency of various oils was above 95 %. After 15 separation cycles for N-hexane and water mixture, the separation efficiency was still above 96 %. The simple anodic oxidation method can complete the construction of micro-nano composite structure of 316L stainless-steel mesh within 5 min, which has high preparation efficiency, and the superhydrophobic stainless-steel mesh can also be reused.