Preparation of superhydrophobic and superoleophilic polypropylene fibers with application in oil/water separation

A novel type of fiber material for the separation of oil/water mixed liquids has been prepared by the chemical vapor deposition of hydrophobic silanes on commercially available polypropylene (PP) fiber. To achieve this, the PP fiber materials were first etched by concentrated H2SO4. Then, the as-prepared PP fiber materials were immersed in highly concentrated suspension of graphene oxide modified by amine-functionalized SiO2 nanoparticles (SiO2–GO). Finally, the as-prepared PP fiber materials were treated by the chemical vapor deposition of hydrophobic silane (octyltrichlorosilane) to form a superhydrophobic surface with a water contact angle more than 156o. The hydrophobic lightweight PP fiber materials are almost instantly filled with the oil phase when selectively absorbing oil from water. The oil can also be drained from the absorbed PP fiber materials. Moreover, the PP fiber material shows the good performance for repeated use.