Developing a new superhydrophilic and superoleophobic poly(4-(1-vinyl-1H-imidazol-3-ium-3-yl) butane-1-sulfonate): vinyl imidazole@Perfluorooctanoic acid@SiO2 coated stainless steel mesh for highly efficient, stable, and durable oil/water separation

The design and development of efficient approaches for water-oil separation have had widespread interest. Most previously introduced techniques and materials used for development of the successful separation of oily wastewater could not answer all the desired demands, such as being efficient and environmentally and economically friendly. Therefore, in seeking a novel method capable of answering these expectations, surfaces with special wettability were introduced. A novel, reusable, and recyclable superhydrophilic and superoleophobic poly(Vsim-Vim)@PFOA@SiO2 nanocomposite-coated stainless steel mesh was synthesized through a facile preparation process. Since the most important factors of these coatings are their oleophobicity and hydrophilicity values, the water contact angle (WCA) and the oil contact angle (OCA) were measured. The coating indicated the excellent characteristics in which the results showed that WCA was 0 degrees, while OCA was 142 degrees, which confirmed remarkable superhydrophilicity and superoleophobicity, respectively. It is worth mentioning that the coating owes its surface behavior mainly to the finer size of mesh and formation of silica, which causes the higher roughness and better oleophobicity, reduction of the surface energy of the synthesized poly(Vsim-Vim)@SiO2 nanocomposite by PFOA, the formation of hierarchical micro-nanometer scale roughness structures on the coating surface, and stable adhesion of SiO2 nanoparticles into poly(Vsim-Vim). Eventually, superb oil/water separation efficiency of 95% with high stability was attained. This result implied that the fabricated coating is a suitable candidate for water-oil emulsion separation which can potentially be employed in green industrial applications. Also, we believe this approach provides a potential application in controllable oil/water separation in large volumes.

Automated summary

The novel coating with superhydrophilic and superoleophobic properties demonstrated excellent oil-water separation efficiency of 95%, making it a promising candidate for green industrial applications.