Fabrication of cost-effective and antifouling Al2O3-SiO2 membrane for efficient oil emulsion separation

Ceramic membrane technology is effective for oil emulsion separation, while its low permeance and fouling issue yield high energy consumption in practical applications. Herein, a series of ceramic membranes were fabricated by incorporating the SiO 2 sintering aid into Al 2 O 3 ceramic powder using a compression molding method. Due to the melting and recrystallizing of SiO 2 on the surface of coarse grains, the modified ceramic membrane exhibited the underwater superoleophobicity property. After optimizing the fabrication conditions, including sintering temperature, molar ratio of Al 2 O 3 /SiO 2 and molding pressure, the modified ceramic membrane had a pure water permeance of 1319 L·m −2 ·h −1 ·bar −1 and a petroleum ether rejection rate of 97.1 %. In addition, the increase in the square quartz phase narrowed the pore size and improved the hydrophilicity of the ceramic membrane, thereby alleviating the pore blocking and enhancing the flux recovery. The flux recovery rate was about 86.1 % after the sodium hydroxide backwashing. This study presents a rational strategy for developing ceramic membranes with scalable potential for efficient oil emulsion separation.