Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials, University of Wollongong , Wollongong, New South Wales 2500, Australia.
Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of the Ministry of Education, School of Chemistry and Environment, Beihang University , Beijing 100191, People's Republic of China.
ACS Nano. 2017 Mar 28;11(3):2477-2485. doi: 10.1021/acsnano.6b07918. Epub 2017 Jan 25.
Developing an effective system to clean up large-scale oil spills is of great significance due to their contribution to severe environmental pollution and destruction. Superwetting membranes have been widely studied for oil/water separation. The separation, however, adopts a gravity-driven approach that is inefficient and discontinuous due to quick fouling of the membrane by oil. Herein, inspired by the crossflow filtration behavior in fish gills, we propose a crossflow approach via a hydrophilic, tilted gradient membrane for spilled oil collection. In crossflow collection, as the oil/water flows parallel to the hydrophilic membrane surface, water is gradually filtered through the pores, while oil is repelled, transported, and finally collected for storage. Owing to the selective gating behavior of the water-sealed gradient membrane, the large pores at the bottom with high water flux favor fast water filtration, while the small pores at the top with strong oil repellency allow easy oil transportation. In addition, the gradient membrane exhibits excellent antifouling properties due to the protection of the water layer. Therefore, this bioinspired crossflow approach enables highly efficient and continuous spilled oil collection, which is very promising for the cleanup of large-scale oil spills.
开发有效的大规模溢油清理系统具有重要意义，因为它们会造成严重的环境污染和破坏。超润湿膜在油水分离方面得到了广泛的研究。然而，由于膜很快被油污染，这种分离采用的是重力驱动方法，效率低且不连续。受鱼鳃的错流过滤行为的启发，我们提出了一种通过亲水、倾斜梯度膜进行溢油收集的错流方法。在错流收集过程中，随着油水平行于亲水膜表面流动，水逐渐通过孔过滤，而油则被排斥、输送并最终收集储存。由于水封梯度膜的选择性导通行为，底部大孔径具有高水流通量有利于快速水过滤，而顶部小孔径具有强的拒油性，便于油的输送。此外，由于水层的保护，梯度膜具有优异的抗污染性能。因此，这种仿生错流方法能够高效、连续地收集溢油，非常有希望用于大规模溢油的清理。
