Fabrication of superhydrophobic/oleophilic membranes by chemical modification of cellulose filter paper and their application trial for oil-water separation

Water-oil separation from their emulsions and mixtures has been a prominent topic in fundamental research and in industries. A superhydrophobic/oleophilic membrane (SHP) was obtained by dipping a cellulose filter paper in an acetonitrile solution of toluene diisocyanate (TDI) and in that ofN-(2,4-diaminophenyl) maleimide, alternatively and repeatedly for three times, to make the paper coated by maleimide-containing polyurea (PU), which was then reacted withn-dodecanethiol (DAT) through Michael addition to obtain the superhydrophobic porous membrane (SHP). All the involved reactions were confirmed by different techniques. SHP membrane as prepared was demonstrated to be superhydrophobic and oleophilic and of high performance in separation of oil and water from their emulsions and mixtures. This study provides a new route to the fabrication of new materials of high superhydrophobicity and oleophilicity, featured by ease of fabrication, low-cost and versatile availability of the starting materials, both synthetic and natural. Graphic abstract