Bamboo-leaf-derived SiO₂ nanoparticles for filtration and antifouling electrospun PAN membranes in oil-in-water emulsion separation

Surface engineering of filter membranes with hydrogels for oil-in-water emulsion separation

This review provides a brief introduction to filtration membranes with superwetting surfaces applied to oil/water emulsion separation and includes comprehensive discussions about the fabrication methods of each filtration membrane, which is expected to advance the development of biomimetic surface membranes for oil/water emulsion separation.

Layer-by-layer construction of super-hydrophilic and self-healing polyvinylidene fluoride composite membrane for efficient oil/water emulsion separation

Due to highly adhesive property, crude oil is easier to adhere on foul filtration membranes. Separation of crude oil‐in‐water emulsion is a continuing tough work. Hydrogels with low‐adhesive superoleophobicity are ideal materials for modifying filtration membranes to achieve efficient and antifouling separation of crude oil‐in‐water emulsion. A key challenge in fabricating the hydrogel modified filtration membranes is to design an ultrathin hydrogel layer with sufficient anti‐crude‐oil‐fouling ability and with controllable thickness, thus not blocking the micro‐ and nanosized membrane pores. Inspired by the novel harsh‐environment‐tolerant superoleophobicity of alginate‐rich seaweed, the construction of an ultrathin Cu2+/alginate hydrogel multilayer with controllable thickness at the nanometer scale on a polymer filtration membrane via a layer‐by‐layer self‐assembly method is achieved. Both the nanosized pores and the high flux of original membrane are well‐maintained. The Cu2+/alginate multilayer modified ultrafiltration membrane behaves a biomimetic superhydrophilicity, underwater superoleophobicity, and antifouling ability for crude oil. It is capable of efficiently separating crude oil‐in‐water emulsion with a high water flux of 1230 L m−2 h−1 bar−1, an ultrahigh efficiency of 99.8%, and an outstanding antifouling and cyclic ability. What's more, the membrane exhibits good salt‐tolerance, antibacterial ability, and long‐term stability.

An electrospun iron oxychloride/polyacrylonitrile nanofibrous membrane with superhydrophilic and excellent regeneration properties: Achieving superior oil-in-water emulsion separation

Underwater oleophobic PTFE membrane for efficient and reusable emulsion separation and the influence of surface wettability and pore size

Preparing ceramic membranes for oil-in-water emulsions separation with oil-based drilling cutting pyrolysis residues (ODPRs) as raw material

Hybrid aerogels derived from banana peel and waste paper for efficient oil absorption and emulsion separation

High-strength, super-hydrophilic alginate electrospun nanofibrous membranes for rapid oil-water emulsion separation

The filtration membranes have been acknowledged as efficient way for separation of emulsion. Nevertheless, most of the methods have limitations of high cost and complex fabrication process. Here, we present a simple method for preparing superhydrophobic/superoleophilic filter paper by solution immersion process. The superhydrophobic filter paper exhibited high selectivity for oil–water mixture. Importantly, the filter paper can be applied to separate surfactant-stabilized water-in-oil emulsion. Separation process is achieved by one step under gravity. Moreover, the superhydrophobic filter paper maintains stable superhydrophobicity and emulsion separation property after using for five cycles. We expected that this low-cost process can be used for water-in-oil emulsion separation.

Rational construction of highly transparent superhydrophobic coatings based on a non-particle, fluorine-free and water-rich system for versatile oil-water separation

A wood-based MOF membrane with high flux and efficiency for oil-in-water emulsions separation

Cupric phosphate mineralized polymer membrane with superior cycle stability for oil/water emulsion separation

In order to achieve efficient micron-scale water-in-oil emulsion separation, a facile and effective strategy is developed to prepare a super-hydrophobic/super-oleophilic fiberglass filter membrane (FGm). Methyl-trichlorosilane (MTS) is successfully cross-linked on the surface of the fiberglass filter membrane (FGm) and aggregates into a 3D nanowire array to provide low surface energy. Nano fumed hydrophobic silica (SH-SiO2) is used to construct the well-defined nanosphere structure on the surface of FGm and enhance the ability of the membrane to resist extreme conditions. The optimally modified membrane displays outstanding super-hydrophobic properties with a contact angle of 156.2°. It is impressive to find that the MTS@SH-SiO2@FGm not only demonstrates the ability to separate water-in-oil emulsions with a particle size of less than 20 μm, but also the removal efficiency of separation has reached 99.98%. More attractively, the membrane still has stable super-hydrophobic features and reusable water-in-oil emulsion separation performance even under exposure to diverse harsh conditions, including extremely acidic corrosive solutions and ultra-high temperature systems.

Common filter membranes for emulsion separation often require time-intensive preparation and extensive use of chemicals, necessitating a fast-processing and eco-friendly alternative. This study introduces a 2-layer stacked nylon mesh treated with surface diffuse atmospheric plasma (SDAP) for rapid and efficient emulsion separation. Commercial nylon mesh exhibited durable super-wetting properties after just 30 s of SDAP treatment, which was sufficient for effective emulsion separation. Multi-layer stacking further enhanced the oil-blocking capacity, with pre-wetted 2-layer meshes achieving over 98% separation efficiency, a flux exceeding 56 000 L m-2 h-1 bar-1 and excellent anti-aging performance, demonstrating applicability across various emulsions simultaneously. The emulsion droplet dynamics within the filter cake revealed high efficiency, offering valuable insights into membrane fouling issues. Furthermore, this work develops SDAP as a promising approach for material treatment, owing to its fast and environmentally friendly processing, scalable set-up and effectiveness under atmospheric conditions.