CORK MEMBRANE FOR EFFICIENT OIL AND WATER SEPARATION

Cork is a renewable, biocompatible, environmentally friendly and abundant biological material with microscale cellular structure. Fabrication of filtration membranes for the separation of oil and water by utilizing such natural materials to replace nonnatural membranes is a green method. A cork membrane with a water contact angle greater than 150 degrees and an oil contact angle close to 0 degrees was fabricated by chemically modifying cork membranes with 1H, 1H, 2H, 2H-perfluorodecyltrichlorosilane. The special wettability was achieved owing to the cellular structure and the surface composition of the cork membrane. Just like nonnatural filtration membranes, natural cork membranes exhibited excellent permeability for oils. After at least 40 cycles of oil-removal processes, the separation efficiency of the membrane was still above 99.1%. Under harsh conditions such as strong acid/alkali, high humidity, and high temperature environments, the wettability and separation efficiency exhibited excellent stability and durability. This method offers an opportunity to the practical applications of the superhydrophobic cork membrane.