Cellulosic fiber filter with special wettability for efficient water/fuel oil separation

Abstract

Hydrophobic/oleophilic filters have great potential for application in oil/water separation. Herein, we describe the successful preparation of environment friendly superhydrophobic cellulosic fiber filter to remove water from diesel. The modified TiO2 particles were used to fabricate the rough structure of superhydrophobic filter paper via a dip-coating method with epoxy resin as a binder. With the further dipping modification by hexadecyltrimethoxysilane (HDTMS), the filter paper obtained excellent water-resistance with water contact angle (WCA) ranging from 126.0° to 151.8°, and strong stability against acid, alkali and UV lights. In this work, it was found that the WCA was proportional to the surface roughness. The obtained hydrophobic filter papers could selectively absorb oil from water-containing fuel oil and could separate water/fuel oil mixture very efficiently with separation efficiency higher than 99%. This simple and mild strategy would inspire the large-scale fabrication of multifunctional surfaces for practical applications in water/oil separation.