Facile Preparation of a Robust Superhydrophobic Ceramic Composite Membrane for Oil/Water Mixture Separation

Superhydrophobic membranes have been extensively applied in oil/water separation processes. Developing a facial approach toward fabricating a robust superhydrophobic ceramic membrane for efficient oil/water (including emulsified systems) separation is critical to mitigate the danger of oil contamination. Herein, we propose a strategy for fabricating superhydrophobic ceramics using a dual cross-linking mechanism. This approach, which leverages epoxy–amine addition reactions to create strong interfacial bonds among amino-mesoporous SiO2 nanoparticles, low-surface-energy modifiers, and the porous ceramic substrate, successfully constructs a robust micro/nanohierarchical PDMS-based organic–inorganic composite superhydrophobic coating. The resulting CLPDMS@NH2-MSN@CM membranes exhibit exceptional superhydrophobicity, self-cleaning capability, efficient separation of various oil/water immiscible mixtures and water-in-oil emulsions, and remarkable interfacial durability and stability. The CLPDMS@NH2-MSN@CMs exhibited exceptional superhydrophobicity, with the water contact angle (WCA) up to 156° and the water sliding angle (WSA) as low as 1.6°. It demonstrated a high separation efficiency up to 99.9% for both immiscible oil/water mixtures and water-in-oil (W/O) emulsions. It sustained over 98.4% efficiency after 40 cycles of repeating separation. In summary, the CLPDMS@NH2-MSN@CM membranes fabricated through dual cross-linking strategies exhibit exceptional durability, high separation efficiency, and scalable fabrication. These properties indicate the potential for application across various hydrophilic porous ceramic substrates, potentially offering innovative solutions for practical oil/water separation, oil resource recovery, and oily wastewater treatment applications.