Electrospun PVDF-SiO2 nanofibrous membranes with enhanced surface roughness for oil-water coalescence separation

Abstract Oily wastewater pollution is considered as one of the most serious global environmental problems. Treating oily wastewater is particularly important and challenging because emulsified oil was difficult to be effectively and economically removed from wastewater. In this work, a novel rough poly(vinylidene fluoride) (PVDF)-SiO2 nanofibrous membrane based on the commercial nylon medium was developed via a facile one-step electrospinning approach by assembling SiO2 nanoparticles for effective coalescence separation of oily wastewater. The PVDF-SiO2 nanofibrous membrane showed high hydrophobicity with water contact angle 135o in air and poor oleophilicity with oil contact angle 87° under water. The membrane performed high coalescence separation efficiency of 98.6% for hexadecane-in-water emulsion. Besides, the nanofibrous membrane exhibited good separation performances with different flow velocities, initial oil concentrations and types of oil-water systems, which showed high potentials in oily wastewater treatment.