Abstract: A mass of oil-water mixture is generated in oil exploitation, and a large amount of oil-water wastewater is produced in our daily life. If these oily wastewaters are not treated effectively, direct discharge would cause serious damage to the natural ecology. How to deal with these oil-water mixtures is a critical issue of environmental protection and sustainable development. Due to the different composition and dispersion form of oily wastewater, and the harsh condition in the actual treatment process, the separation method should be selected to satisfy the separation requirements. Membrane separation is a common oil-water separation method. The separation principle is based on the different affinity of oil and water to the solid film surface. However, due to the diversity of separation environments and the limited mechanical properties of membrane materials, membrane separation has encountered kinds of challenges in industrial applications, especially for the high concentration of oil in water. In this work, nickel foam with good mechanical properties is used as filtration materials, and nano-structures are constructed on its surface to enhance the roughness of substrate surface and the underwater oil-repellency, so as to improve the oil-water separation performance. By electrochemical deposition method, copper particles are deposited on the surface of nickel foam. The surface structure and properties of the separation film are characterized by X-ray diffractometer, surface roughness tester and contact angle tester. The oil-water separation property to different kinds of oil and the stability of the prepared separation film are tested. The results show that the membrane has a high separation efficiency for different kinds of oil and good cycling separation performance, and the separation efficiency is more than 95% after ten cycles. This study shows the effectiveness of surface engineering in the development of efficient membrane for oil-water separation, and expands the applications of electrodeposition approach to surface modification.

Key words: Nickel sponge, Surface structure, Electrochemistry, Diffusion limitation, Oil and water separation

摘要： 石油开采过程中会产生大量的油水混合物，每天生产生活中也会产生大量含油废水，如何处理这些油水混合物，是环境保护和可持续发展的重大需求。针对含油量较高的油水混合物，本工作制备了疏水-超亲油分离膜。以机械性能较好的泡沫镍为过滤基体，采用电沉积方法，在泡沫镍表面沉积铜颗粒，构筑亲油疏水表面。研究了沉积电位和沉积时间对表面结构的影响，并测试了分离膜表面结构、表面粗糙度及水滴在膜表面的接触角，并对所制备的分离膜进行油水分离性能测试和多次循环的稳定性测试。结果表明，所制备的分离膜具有良好的循环分离性能，对于油水混合物循环十次后分离效率仍在90%以上。本研究为高效油水分离膜材料开发提供了新思路，并拓展了电化学表面改性的应用领域。

关键词: 泡沫镍, 表面结构, 电化学, 传质受限, 油水分离