Facile preparation of superhydrophobic/superoleophilic diatomite porous ceramics for efficient oil-water separation

抄録

In this work, a superhydrophobic diatomite porous ceramic was successfully prepared via a straightforward impregnation and heat-treatment way using isobutylene-maleic anhydride copolymer and SiO₂ nanoparticles (NPs) as co-modifier. Due to the removal of the hydroxyl group after 1 h heating at 573 K in a 5 % H₂/Ar atmosphere, the amide group in the original isobutylene-maleic anhydride copolymer was transformed to imide group, endowing the porous ceramics with excellent hydrophobic property. Furthermore, the addition of SiO₂ NPs which enhanced the surface roughness resulted in the superhydrophobic properties of the final products. The continuous oil-water separation test of as-prepared superhydrophobic diatomite porous ceramics exhibited an initial separation flux of over 205.5 kg·min⁻¹·m⁻² with a separation selectivity of over 93 % for various oil-water mixtures. Moreover, their oil-adsorption tests demonstrated an 1.6–57 times adsorption capacity as high as these of other traditional inorganic sorbent materials.