Engineering superhydrophobic-superoleophilic nylon mesh for high-efficiency oil-water separation

ABSTRACT With the aggravation of environmental pollution caused by oil and chemical leakages, oil-water separation has attracted great attention from both academia and industry. In this paper, a costeffective dip-coating and thermal treatment method based on the modification of nylon mesh has been developed for oil-water separation. Ultra-low surface energy polybenzoxazine and hydrophobic silica nanoparticles were adopted to engineer nylon mesh superhydrophobic-superoleophilic. The morphology, chemical composition and surface properties of the modified nylon mesh were characterized by using scanning electron microscopy, Fourier-transform infrared spectroscopy and contact angle (CA) measurements, etc. The modified nylon mesh exhibited excellent superhydrophobic property with a high water contact angle of 154.3° and distinct superoleophilic feature with a negligible oil CA of nearly 0°, leading to more than 99.5% ± 0.1% of oil-water separation efficiency with high permeate flux (up to 1.77 × 10 4 ± 100 L/(m 2 h)) merely under gravity. In addition, the novel nylon mesh displayed excellent reusability after more than 30-cycle measurements. Our findings may provide a promising approach to the treatment of oil spills and oily wastewater.