title: Hygro-responsive membranes for effective oil-water separation.
abstract: There is a critical need for new energy-efficient solutions to separate oil-water mixtures, especially those stabilized by surfactants. Traditional membrane-based separation technologies are energy-intensive and limited, either by fouling or by the inability of a single membrane to separate all types of oil-water mixtures. Here we report membranes with hygro-responsive surfaces, which are both superhydrophilic and superoleophobic, in air and under water. Our membranes can separate, for the first time, a range of different oil-water mixtures in a single-unit operation, with >99.9% separation efficiency, by using the difference in capillary forces acting on the two phases. Our separation methodology is solely gravity-driven and consequently is expected to be highly energy-efficient. We anticipate that our separation methodology will have numerous applications, including the clean-up of oil spills, wastewater treatment, fuel purification and the separation of commercially relevant emulsions.
authors.affiliation: Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors.forename: Arun K
authors.initials: AK
authors.lastname: Kota
authors.forename: Gibum
authors.initials: G
authors.lastname: Kwon
authors.forename: Wonjae
authors.initials: W
authors.lastname: Choi
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Mabry
authors.forename: Anish
authors.initials: A
authors.lastname: Tuteja