高浓度乳化剂引发的界面膜结构稳定性是废弃纳乳液破乳难的主要原因。磁性纳米颗粒因具有界面活性和磁响应性在乳化液破乳研究中引起关注，但针对含高浓度乳化剂纳乳液破乳的研究鲜见报道。本项目对磁性纳米颗粒表面进行特征官能团嫁接，并对颗粒形态和介孔结构进行调控，获得具有乳化剂捕集功能的磁性纳米颗粒(MNPs-EC)。研究磁场作用下MNPs-EC对不同阴/非离子乳化剂稳定的纳乳液的破乳规律，主要从乳化剂网络结构坍塌和液滴粒径时空演变两方面揭示破乳关键过程及影响因素。进一步研究MNPs-EC对油水界面乳化剂的捕集机制及其对界面膜稳定性的影响规律；搭建微流控-液滴磁操控平台探究磁场和MNPs-EC对液滴行为的作用特征，重点解析油滴聚集、聚并、迁移的磁响应力学特征，最终揭示磁场作用下MNPs-EC与油水界面上乳化剂相互作用对液滴行为的影响机制。研究成果为MNPs-EC处理废弃纳乳液提供理论依据和技术支撑。

The densely packed anion/non-ionic emulsifiers on the interface is essential to the exceptional stability of waste cutting nanoemulsion. Magnetic nanoparticles (MNPs) have the features of interfacial activity and mangnetic responsiveness, which have attracted great attention in emulsion breaking. However, the demulsification of nanoemulsion with high concentration of emulsifier has rarely been reported. This research designs a series of functional MNPs to capture emulsifier by modifying its surface composition and creating the mesoporous structure, which were named as MNPs-EC. The different demulsifying characteristics of MNP-CEs were investigated regarding to the anionic/non-ionic emulsifiers stabilized nanoemulsion in a magnetic field. The crucial stages of demulsification process and influencing factors were analyzed from the aspects of structure collapse of emulsifier network as well as spatial-temporal evolution of droplet size. Based on the above results, the influences of MNP-CEs and magnetic field on the emulsifier capture and the stability of interfacial film were studied. The droplet behavior was also studied by setting up the micropipe-magnetic field platform and the microfluidic device-magnetic field experimental platform. The mechanical characteristics of oil droplet coalescence, migration and separation under magnetic field were intensively analyzed to reveal the influence mechanism of the interaction between MNP-CEs and emulsifier on the droplet behavior. This research will provide theoretical basis and technical support for the applications of MNP-CEs in the treatment of practical waste cutting fluid.