Liquid-assisted strategy for dual-purpose oil-water separation with super-omniphobic mesh

Abstract

Sustainable methods for oil–water separation are highly desirable for industries globally as their significant role in various applications, such as the treatments for industrial wastewater or marine oil leakage, which harms the environment and ecology deeply. However, existing super-hydrophobic/super-oleophilic and super-oleophobic/super-hydrophilic surfaces fail to satisfy the requirement of continuous oil–water separation owing to either affinity to viscous oil or poor water resistance. Novel methods available for sustainable oil–water separation are widely desired. Until now, there has been no research conducted on the application of super-omniphobic meshes for oil–water separation. Herein, a liquid-assisted strategy for dual-purpose oil–water separation with super-omniphobic meshes was proposed. The strategy can be applied for oil–water separation by removing either water or oil with high separation efficiency. Meanwhile, by taking advantage of the anti-liquid property of the super-omniphobic mesh, the existing common problems such as viscous oil contamination and caustic aqueous corrosion could be avoided. Moreover, since this strategy adopts super-omniphobic meshes, oil–water separation using this strategy in a harsh environment can also be guaranteed. Compared with the conventional super-wetting meshes for oil–water separation, the strategy proposed in this work ensures that the separation mesh always maintains super-oleophobicity during the oil–water separation process and is universally applicable to a variety of super-omniphobic meshes. The present novel strategy provides a general guide for dual-purpose oil–water separation and a sustainable method for anti-contamination wastewater treatment, which indicates promising applications.