Comparative Analysis of the Stainless Steel Mesh Size Effect on Oil–Water Emulsion Separation with and Without Ni Coating

Oil–water separation is of enormous importance because it has practical implications for addressing corrosion problems in the oil industry, arising from direct contact between the inner surfaces of pipelines and water containing oil. Therefore, the development of functional materials for handling oil–water mixtures is crucial and has significant economic benefits in the future. Using metal meshes remains a complex process because the properties of the extracted oil mixture (emulsion) vary across fields, which can affect the efficiency of the separation process and the required mesh size for optimal results. Still, it is considered a promising approach for separation. In this study, stainless steel meshes of various mesh sizes (180, 200, 300, 400, and 500 meshes) were coated with a 0.1-micron-thick layer of nickel by physical vapour deposition (PVD). The separation efficiency of stainless steel meshes, both with and without Ni coating, was examined at room temperature using an emulsion (50% vol. petroleum and 50% vol. water) prepared in the laboratory. The Ni-coated meshes achieved high separation efficiencies of 97% and 92% for mesh sizes 400 and 300, respectively. An 8% increase in the separation efficiency of the 200 mesh size resulted in about 80% efficiency with a Ni coating. Hence, it can be concluded that the prepared meshes have potential for high-efficiency oil–water separation, which may help reduce water transport to subsequent processing stages and mitigate corrosion-related issues.