An instant oil separation by octadecyl-polysiloxane-reticulated recyclable superhydrophobic polyester fabric

Of all the environmental concerns, water pollution by oily wastewater is arguably one of the most severe problems facing humanity. This universal challenge needs to resolve the effective oil–water​ separation. Hither, an excellent water repellent superhydrophobic material propelled by the lotus leaf were prepared by cross-linking of fumed silica and octadecyltrichlorosilane via polycondensation reactions on polyester fabric by a one-step dip-coating method. The constructed octadecyl-polysiloxane networked silica material exhibits superhydrophobic behavior at a maximum high-water contact angle of 178o. AFM and SEM morphological studies showed nanoscale hierarchy structures forming large-scale microstructures, and they were well-anchored with the fabric. A high oil (dichloromethane) flux up to 1604 L m-2 h-1 with a separation efficiency of nigh >99.5% was obtained even after repeating use for ten separation cycles. The material showed a fast and effective oil–water separation under gravity and has excellent stability over time, which makes it an ideal option for treating industrial oily wastewater.