title: Separating oil-water nanoemulsions using flux-enhanced hierarchical membranes.
abstract: Membranes that separate oil-water mixtures based on contrasting wetting properties have recently received significant attention. Separation of nanoemulsions, i.e. oil-water mixtures containing sub-micron droplets, still remains a key challenge. Tradeoffs between geometric constraints, high breakthrough pressure for selectivity, high flux, and mechanical durability make it challenging to design effective membranes. In this paper, we fabricate a hierarchical membrane by the phase inversion process that consists of a nanoporous separation skin layer supported by an integrated microporous layer. We demonstrate the separation of water-in-oil emulsions well below 1 μm in size. In addition, we tune the parameters of the hierarchical membrane fabrication to control the skin layer thickness and increase the total flux by a factor of four. These simple yet robust hierarchical membranes with engineered wetting characteristics show promise for large-scale, efficient separation systems.
authors: Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge MA 02139.
authors: Brian R
authors: BR
authors: Solomon
authors: Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge MA 02139.
authors: Md Nasim
authors: MN
authors: Hyder
authors: Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge MA 02139.
authors: Kripa K
authors: KK
authors: Varanasi