Zhang, LeileiBai, ChutianZhang, ZhuqingWang, XinglinNguyen, Thao VyVavra, EricPuerto, MauraHirasaki, George J.Biswal, Sibani Lisa2023-08-012023-08-012023Zhang, Leilei, Bai, Chutian, Zhang, Zhuqing, et al.. "Application of magnetic nanoparticles as demulsifiers for surfactant-enhanced oil recovery." <i>Journal of Surfactants and Detergents,</i> 26, no. 3 (2023) Wiley: 401-408. https://doi.org/10.1002/jsde.12658.https://hdl.handle.net/1911/115027Nonionic surfactants are increasingly being applied in oil recovery processes due to their stability and low adsorption onto mineral surfaces. However, these surfactants lead to the production of emulsified oil that is extremely stable and difficult to separate by conventional methods. This research characterizes the stability of crude oil mixed with a nonionic surfactant, L24–22, in a brine solution. When subjected to gravity separation, a middle oil-rich and bottom water-rich emulsion are generated for various water–oil ratios. Thermal treatments can effectively break oil-rich emulsions, but the bottom water layer remains contaminated with micron-sized crude oil droplets. A magnetic nanoparticle treatment is shown to demulsify the crude oil emulsions, dropping the total organic carbon (TOC) in the water layer from 1470 to 30 ppm.engThis work is protected by copyright, and is made available here for research and educational purposes. Permission to reuse, publish, or reproduce the work beyond the bounds of Fair Use or other exemptions to copyright law must be obtained from the copyright holder.Journal articlehttps://doi.org/10.1002/jsde.12658