Zhang Tianyue, Wang Xuejiao, Dong Ying, Li Jing, Yang Xiao-Yu
Hubei Province Key Laboratory of Coal Conversion and New Carbon Materials, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Peace Avenue, Wuhan 430081, China; State Key Laboratory of Advanced Technology for Materials Synthesis and Processing & Shenzhen Research Institute & Laoshan Laboratory, Wuhan University of Technology, 122 Luoshi Road, Wuhan 430070, China; Shenzhen Huazhong University of Science and Technology Research Institute, 9 Yuexing Third Road, Nanshan District, Shenzhen 518000, China.
Hubei Province Key Laboratory of Coal Conversion and New Carbon Materials, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Peace Avenue, Wuhan 430081, China.
J Hazard Mater. 2024 Mar 5;465:133305. doi: 10.1016/j.jhazmat.2023.133305. Epub 2023 Dec 20.
Separating water-in-oil emulsions is important in terms of environmental protection and resource recovery. To address the challenges posed by the water-oil interface, superwetting materials have been designed to accomplish separation through filtration and adsorption. Superhydrophobic membranes prevent the permeation of water droplets owing to extreme repellence and their size-sieving abilities. However, their use in remediating water-contaminated oil is limited by high oil viscosities. Meanwhile, in-air superhydrophilic sorbents are rarely employed for the separation of water-in-oil emulsions due to the thermodynamic and kinetic limitations of water adsorption in oil. Herein, the integration of an under-medium superlyophilic membrane with the hierarchical porous structure of wood is presented for filtration-driven selective adsorption of water from surfactant-stabilized (10 g/L) water-in-oil emulsions. Compared to filtration through a natural wood membrane or direct adsorption using an under-oil superhydrophilic wood membrane, the under-medium superlyophilic wood membrane demonstrated high separation efficiencies of > 99.95% even when applied to the regeneration of high-viscosity lubricating (6.3 mPa s) and edible (50.5 mPa s) oils, exhibiting viscosity-dependent fluxes and excellent stability. Moreover, the cost of purifying 200 mL of lubricating oil using the modified wood membrane was much lower than the oil's market price and required a low energy consumption of ca. 1.72 kWh. ENVIRONMENTAL IMPLICATION: The ever-growing use of petroleum and industrial/domestic oil products has led to excessive (estimated at a million tons per year) output of waste oils. Because direct discharge of waste oils into the environment causes serious pollution problems, separating water-in-oil emulsions is important in terms of environmental protection and resource recovery. Here filtration-driven water adsorption has been demonstrated to be a feasible method for the remediation of water-contaminated waste oils, even those that are highly viscous.
分离油包水乳液在环境保护和资源回收方面具有重要意义。为应对油水界面带来的挑战，人们设计了超润湿性材料，通过过滤和吸附来实现分离。超疏水膜由于具有极强的排斥性及其尺寸筛分能力，可防止水滴渗透。然而，它们在修复受水污染的油方面的应用受到高油粘度的限制。同时，由于油中吸水的热力学和动力学限制，空气中的超亲水吸附剂很少用于分离油包水乳液。在此，我们展示了一种具有木材分级多孔结构的介质下超亲膜，用于从表面活性剂稳定的（10 g/L）油包水乳液中过滤驱动选择性吸附水。与通过天然木材膜过滤或使用油下超亲水木材膜直接吸附相比，即使应用于高粘度润滑（6.3 mPa·s）和食用（50.5 mPa·s）油的再生，介质下超亲木材膜也显示出>99.95%的高分离效率，表现出粘度依赖性通量和出色的稳定性。此外，使用改性木材膜净化200 mL润滑油的成本远低于该油的市场价格，且能耗低，约为1.72 kWh。环境意义：石油以及工业/家用油品的使用不断增加，导致废油产量过高（估计每年达一百万吨）。由于将废油直接排放到环境中会造成严重的污染问题，分离油包水乳液在环境保护和资源回收方面具有重要意义。在此，过滤驱动的水吸附已被证明是一种可行的方法，可用于修复受水污染的废油，即使是高粘度的废油。
