Research advancement on magnetic nanomaterial demulsifier for oil-water separation

A large number of oil–water emulsions are produced in petroleum, petrochemical, and other industries and are stabilized by natural and acquired surfactants or solid particles. If these emulsions are not demulsified, then the oil phase is difficult to separate effectively from the water phase. Moreover, direct discharge will not only cause a waste of oil resources but also harm the ecological environment. Magnetic nanomaterial demulsifier prepared by magnetic nanoparticles (MNPs) has excellent demulsification performance and and is simple, green, and clean to prepare. It can be recycled and has strong application potential. This paper systematically summarizes the demulsification principle, main preparation methods, and various typical applications of magnetic nanomaterial demulsifier, discusses its recycling performance, and presents future development prospects. This paper has reference value for the design, synthesis, and application of new magnetic nanomaterial demulsifier.