Facile fabrication of anti-corrosive superhydrophobic diatomite coatings for removal oil from harsh environments

Abstract

The separation of oil/water mixtures under acidic, alkaline and salty conditions remains a great challenge. Facile, low-cost and easily scale-up processes for the fabrication functional materials to effective oil/water separation under harsh environment are urgently desired. Herein, a superhydrophobic diatomite coating was successfully fabricated by a facile one-step spray-coating process for the gravity driven separation of oil/water mixtures in strong acidic, alkaline and salty environments. In addition, the as-prepared superhydrophobic diatomite-coated meshes can separate a series of oil/ water mixtures with separation efficiency up to 99.8%. Moreover, the as-prepared coated mesh still maintained a separation efficiency exceeding 99.5% and stable recyclability after 40 separation cycles. Meanwhile, the electrochemical corrosion test results indicated that the superhydrophobic coating maintained excellent chemical stability and corrosion resistant effect in 3.5 wt% NaCl solutions. Therefore, our work provides a facile method to fabricate the superhydrophobic diatomite coatings with outstanding anti-corrosive property that can be used for removal oils from harsh environment.