Enhanced flux of PDA@SiO2 ceramic membranes by metal mesh-assisted phase inversion method for efficient separation of oil-in-water emulsions

The pore structure and surface properties of ceramic membranes lead to a low separation flux, which limits their further application. Changing the microstructure of membranes by introducing new technologies is a very effective method. In this study, high flux ceramic substrate membranes were prepared by metal mesh-assisted phase inversion method, and then new PDA@SiO 2 ceramic membranes were prepared by introducing PDA@SiO 2 core-shell structure. During the phase inversion, the metal mesh pores restrict the path of the water nuclei to extract the polymer, and the microchannels grow along the extraction path, creating a uniform pore size above the metal mesh and removing the dense layer below, allowing the ceramic substrate membranes to exhibit high fluxes. PDA@SiO 2 core-shell structures were stably grown on the surface of ceramic membranes by vacuum self-assembly. Due to the introduction of hydrophilic groups and micro-nano scale roughness, the PDA@SiO 2 ceramic membranes exhibit super-hydrophilic/underwater super-oleophobic performance, stabilizing the separation of oil-in-water emulsions with excellent permeation fluxes (1058 L·m⁻²·h⁻¹·0.2 bar⁻¹) and oil removal rate (99 %). PDA@SiO 2 ceramic membranes exhibit excellent stability, fouling resistance, and durability in harsh environments, contamination tests, and cycling tests. Excellent oil-water separation, stability, and durability make PDA@SiO 2 ceramic membranes a promising solution for the treatment of oil-in-water emulsions.