Superhydrophobic Hair-Like Nanowire Membrane for the Highly Efficient Separation of Oil/Water Mixtures

Abstract

Water pollution caused by oil leakage and oily wastewater has become a serious environmental problem. Therefore, it is important to develop an efficient material to remove oil from water. Given the cost and efficiency, the membrane with superhydrophobicity is the most used material for the separation of oil/water mixtures. However, many works have been done through modification with a fluorinated reagent, causing high cost and damage to the environment. In this work, a simple and fast two-step method is employed to achieve a superhydrophobic hair-like nanowire membrane. Through the alkali-assisted oxidation process and modification with nonfluorinated low surface energy chemical, the so-obtained membrane (denoted as SHM), with the water contact angle of about 164°, exhibits excellent separation efficiency for binary mixtures of water and oils (toluene, hexane, gasoline, and so on). Meantime, this membrane also exhibits excellent durability and reusability in the long-term separation process, indicating its great potential for practical application in the future.

Fabrication of a Janus Copper Mesh by SiO2 Spraying for Unidirectional Water Transportation and Oil/Water Separation

“…Recently, oil/water separation technologies based on materials with unique wettability have attracted global attention as a result of their advantages of simplicity, recyclability, and inexpensive costs. − In comparison to traditional single- and switchable-wettability membranes for oil/water separation, , the Janus membranes have particular liquid transport behaviors because of their unique asymmetric wettability, showing excellent separation performances as well as expansion in the construction of three-dimensional (3D) porous materials with superwettability . Janus membranes with asymmetric surface wettability on two sides allow water droplets to transport unidirectionally from the hydrophobic side to the hydrophilic side while preventing the penetration of water droplets from the hydrophilic side to the hydrophobic side. − As a result of these fascinating and unique properties, Janus membranes exhibit great potential for applications in oil/water separation, − unidirectional liquid transportation, ,, fog collection, membrane distillation, , sensors, Janus liquid diode, , demulsification of oil, , etc.…”

Icephobic Performance of Combined Fluorine-Containing Composite Layers on Al-Mg-Mn–Si Alloy Surface

“…Impacting the icephobic properties of a surface is a particular complex of measures directed at its modification to provide the lowest adhesion of water droplets at low temperatures to avoid ice crystal growth. Superhydrophobic surfaces (i.e., surfaces characterized by a high value of the contact angle (CA), a low contact angle hysteresis and a sliding angle of less than 10 • ) can retain an air layer between water and structural elements, forming the surface relief and preventing droplet retention on the surface of the material [1][2][3][4][5][6][7][8]. It is noted that superhydrophobic surfaces enhance the rebound of falling liquid droplets at low substrate temperatures and high relative humidity [9].…”