Cupric Phosphate Nanosheets-Wrapped Inorganic Membranes with Superhydrophilic and Outstanding Anticrude Oil-Fouling Property for Oil/Water Separation

Abstract

Developing an effective and sustainable solution for cleaning up or separating oily water is highly desired. In this work, we report a completely inorganic mesh membrane made up of cupric phosphate (Cu(PO)) in a special intersected nanosheets-constructed structure. Combing the hierarchical structure with strong hydration ability of Cu(PO), the nanosheets-wrapped membrane exhibits a superior superhydrophilic and underwater anti-oil-fouling and antibio-fouling property for efficient oil/water separation to various viscous oils such as heavy diesel oil, light crude oil, and even heavy crude oil with underwater oil contact angles (CAs) all above 158° and nearly zero underwater oil adhesive force even when a large preload force of up to 400 μN was applied on the oil droplet. Simultaneously, the membrane exhibits a high chemical and thermal stability and outstanding salt tolerance. Continuous separation operated on a cross-flow filtration apparatus demonstrates a large separation capacity and long-term stability of the membrane during treating a 2000 L crude oil/water mixture with constantly stable permeating flux of ∼4000 L/m h and oil content in the filtrate below 2 ppm. The excellent anti-oil-fouling property, high separation capacity, and easily scaled-up preparation process of the membrane show great potential for practical application in treating oily wastewater.

Polyphenol‐Sensitized Atomic Layer Deposition for Membrane Interface Hydrophilization

“…[ 14 ] For the membrane without TA‐sensitized treatment (Pristine‐70× showed an initial water contact angle of 54° and a long infiltration time of the water droplet), the permeate flux cannot be recovered as the poor hydration ability could not defend against viscous crude oil contamination. [ 15 ]…”

Micro‐/Nanostructured Interface for Liquid Manipulation and Its Applications

“…Based on the principles mentioned above, novel materials were invented and fabricated as proof‐of‐concept. Oil–water separators are generally porous meshes, foams and sponges made from a wide range of materials, including metal, polymers, ceramics, fabrics, cellulose‐based derivatives, particles, and novel nanomaterials . Recently, Wang et al reported a highly compressible wood sponge with spring‐like lamellar structure (Figure b–d), which was fabricated by sequential chemical treatment, freeze drying and chemical vapor deposition of natural balsa wood.…”

One-step electrodeposition to fabricate superhydrophobic coating and its reversible wettability transformation

“…Since the as-prepared meshes are superhydrophobic or superoleophilic that can be a practical property for oil spill clean [31][32][33][34]. We investigate the oil absorption ability of the brick red superhydrophobic and black superhydrophilic meshes.…”