Preparation of Superhydrophobic Polyurethane Sponge for Oil/Water Separation

Oil spillage and industrial oily wastewater have caused severe environmental concerns. The main goal of this research is fabrication of a suitable sorbent for separation of hydrocarbon contaminants from water. Superhydrophobic porous materials have great potential for oil absorption due to their good stability, high absorption capacity and recyclability. Polyurethane (PU) sponge that is a 3D porous material was selected due to its suitable structural properties. PU has hydrophilic nature while a desirable sorbent must be hydrophobic and thus, the surface of sponge was modified. Grapheneoxide (GO) nanoparticles and octadecylamine (ODA) were chosen as coating materials. Naturally GO has hydrophilic functional groups that were removed by means of dopamine and its polymerization to polydopamine. Furthermore, polydopamine caused GO and ODA to bind on the skeleton of PU sponge. Water contact angle of processed sponge was 155.33 and that showed the as-prepared sorbent has become superhydrophobic. Absorption capacity of sponges for kerosene, diesel, and sesame oil were measured to be 49.07±0.58 g.g-1, 50.20±0.79 g.g-1 and 51.03±0.87g.g-1, respectively.