Abstract Removing process water from crude oil emulsions is critically required prior to their downstream processings. In this work, cellulose-coated magnetic Janus nanoparticles (MJ NPs) of asymmetric surface wettability were applied to dewatering crude oil emulsions under an applied magnetic field. Despite the asphaltene film stabilizing emulsified water droplets, the MJ NPs showed stronger interfacial activities, making more secure deposition at the interface as compared with interfacially active magnetic nanoparticles (IM NPs) of uniform surface modification. The MJ NPs could remove > 90 % water from the emulsions of different water contents, showing their robust dewatering ability. The spent MJ NPs were regenerated via standard washing, drying and resuspension process, and reused for at least six cycles while retaining excellent interfacial activities and high dewatering efficiency. Due to the coating of environmentally benign and biodegradable celluloses, the MJ NPs could achieve excellent dewatering without generating secondary hazards to the crude oil.

中文翻译：

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纤维素包被的磁性 Janus 纳米颗粒用于原油乳液的脱水

摘要 在进行下游加工之前，迫切需要从原油乳液中去除工艺用水。在这项工作中，将具有不对称表面润湿性的纤维素涂层磁性 Janus 纳米粒子 (MJ NPs) 应用于外加磁场下的原油乳液脱水。尽管沥青质膜稳定了乳化水滴，但与均匀表面改性的界面活性磁性纳米粒子 (IM NPs) 相比，MJ NPs 表现出更强的界面活性，使界面处的沉积更安全。MJ NPs 可以从不同含水量的乳液中去除 > 90% 的水，显示出其强大的脱水能力。用过的 MJ NPs 通过标准的洗涤、干燥和再悬浮过程再生，并重复使用至少六个循环，同时保持优异的界面活性和高脱水效率。由于包覆对环境无害且可生物降解的纤维素，MJ NPs 可以实现出色的脱水效果，而不会对原油产生二次危害。