Selective separation of oil and water with mesh membranes by capillarity

Abstract

The separation of oil and water from wastewater generated in the oil-production industries, as well as in frequent oil spillage events, is important in mitigating severe environmental and ecological damage. Additionally, a wide arrange of industrial processes require oils or fats to be removed from aqueous systems. The immiscibility of oil and water allows for the wettability of solid surfaces to be engineered to achieve the separation of oil and water through capillarity. Mesh membranes with extreme, selective wettability can efficiently remove oil or water from oil/water mixtures through a simple filtration process using gravity. A wide range of different types of mesh membranes have been successfully rendered with extreme wettability and applied to oil/water separation in the laboratory. These mesh materials have typically shown good durability, stability as well as reusability, which makes them promising candidates for an ever widening range of practical applications.

A stable ZIF-8-coated mesh membrane with micro-/nano architectures produced by a facile fabrication method for high-efficiency oil-water separation

“…5b). The performances of the ZIF-8-coated membrane were among the best reported [12]. In addition, after the oil-water mixtures were separated, the ZIF-8-coated mesh membrane can be easily recovered by simply washing the surface with ethanol, possessing good recyclability.…”

“…Recently, membrane technologies have attracted increasing interest in the separation application as a promising and economical approach [9][10][11]. Mesh membrane for separating oil-water mixture driven by capillarity has been recognized as an effective way to achieve high flux and separation efficiency [12][13][14][15][16]. Some polymers, such as polytetrafluoroethylene (PTFE), polydimethylsiloxane (PDMS) and poly(stearylmethacrylate) (PStMA) have been successfully applied on mesh membranes [17,18], however, owing to their oleophilic property, the surface of these membranes is easily polluted or even blocked up by oil [19].…”

Corrosion resistance for superwetting immiscible oil/water separation porous materials

“…5 Therefore, many superwettability materials such as coating meshes, [6][7][8] sponges, [9][10][11] membranes, [12][13][14][15] foams, 16,17 textiles, 18,19 aerogels, 20,21 particles, 22,23 and others [24][25][26] are applied for oils/water separation. [27][28][29][30] Superwetting porous copper foam with superhydrophobicity and superoleophilicity are of greatest concern since these materials are affordable and well-prepared 3 dimensional (3D) network composite structures and large surface area compared with their counterparts in the form of membrane, sponges, textiles, ber and particle. [31][32][33][34][35][36][37] Moreover, the material could achieve the rapid separation of sundry immiscible oil/water mixtures and high adsorption capacity with superwettability caused by the hierarchical micro-nano structures and chemical compositions, revealing the coactions of structure and performance.…”

Review on Membranes for the Filtration of Aqueous Based Solution: Oil in Water Emulsion

“…With increasing industrial development and rapid population growth, discharging of oily wastewater from the activity and process of different industries such as, petrochemical, beverages, metal-finishing, metallurgical, food industries etc. is increasing at alarming rate, causing unprecedented harm to natural environment and human being and this is due to the fact that oil is flammable and also can decompose to form other harmful chemical, further aggravating pollution in the environment and adversely affects aqueous habitants and human's health [1][2][3][4][5][6]. Besides, Oily waste water is one of the factor that cause water pollution, which can have a concentration of 100-5000 mg/L or higher, depending on the nature of crude oil [7].…”

“…These are surface membrane with super-hydrophobic and super-oleophilic or surfaces with the inverse wettability that are super-oleophobic and super-hydrophilic. When such surface membranes are fabricated and subjected to oil/water mixture, it preferentially attract one of the phase in order to reduce the overall interfacial energy of the system [2].…”