【摘要】 含聚合物老化油具有机械杂质含量高、乳化严重、黏度大、界面膜强度高以及稳定性好等性能特点，采用常规破乳剂存在筛选困难、渗透性差、破乳温度高和破乳剂用量大等诸多问题。在常温常压条件下，采用氧化还原法将Fe²⁺氧化成Fe₃O₄纳米颗粒的同时原位沉积在还原后的氧化石墨烯（rGO）表面，制备出一种磁性复合纳米材料Fe₃O₄-rGO,利用TEM、SEM、FTIR、XRD和XPS分别对Fe₃O₄-rGO的形貌、结构和化学性质进行了表征，证实Fe₃O₄-rGO是一种Fe₃O₄负载于还原氧化石墨烯层状结构中的二维片状纳米材料。低温条件下，在使用质量分数为0.04%的Fe₃O₄-rGO时，对老化油的破乳率可在2 h内达到90%以上且水相清澈，随着温度升高，Fe₃O₄-rGO对老化油的脱水率和脱水速率明显提升，在80℃条件下，脱水率高达98.0%;还研究了pH对Fe₃O₄-rGO破乳效率的影响，发现酸性和中性条件下（pH=2.2～6.8）,Fe₃O₄-rGO表现出较高的破乳效果，碱性条件下，破乳效果较差，主要是因为pH低于6.8时，Fe₃O₄-rGO与乳液液滴间以静电引力为主，Fe₃O₄-rGO可以与界面活性物质结合较好，从而破坏界面膜，随着pH增大，Fe₃O₄-rGO与乳滴之间的静电斥力增大，难以吸附到界面膜上，从而导致破乳效果下降。最后，Fe₃O₄-rGO的可回收性大大降低了破乳剂的使用成本，降低破乳剂的污染。该研究不仅为含聚合物老化油的分离提供了一种高性能且可回收的破乳剂，也为新型磁性复合纳米材料的制备提供了一种思路。更多还原

【Abstract】 Polymer-containing aged oil has the characteristics of high mechanical impurity content, severe emulsification, high viscosity, high interfacial film strength and good stability.The use of conventional demulsifiers presents many problems such as difficult screening, difficult penetration, high demulsification temperature and large demulsifier dosage.In this study, under normal temperature and pressure conditions, Fe²⁺ as oxidized to Fe₃O₄ nanoparticles by the redox method and simultaneously in-situ deposited on the surface of reduced graphene oxide（rGO） to prepare a magnetic composite nanomaterial Fe₃O₄-rGO.The morphology, structure and chemical properties of Fe₃O₄-rGO were characterized by TEM, SEM, FTIR, XRD and XPS, respectively, confirming that Fe₃O₄-rGO is a two-dimensional flake nanomaterial with Fe₃O₄ loaded in the layered structure of rGO.At low temperatures, when the usage concentration is 0.04%, thedemulsification rate of aged oil can reach over 90% within 2 hours, and the water phase is clear.As the temperature increases, the dehydration rate and dehydration efficiency of Fe₃O₄-rGO for aged oil significantly improve.At 80 ℃, the dehydration rate is as high as 98.0%.The effect of pH value on the demulsification efficiency of Fe₃O₄-rGO was also studied.It was found that Fe₃O₄-rGO shows high demulsification effect under acidic and neutral conditions（pH = 2.2～6.8）,while the demulsification effect is poor under alkaline conditions.This is mainly because when the pH value is below 6.8, the electrostatic attraction between Fe₃O₄-rGO and emulsion droplets is dominant, and Fe₃O₄-rGO can well combine with interfacial active substances, thereby destroying the interfacial film.As the pH value increases, the electrostatic repulsion between Fe₃O₄-rGO and emulsion droplets increases, making it difficult for Fe₃O₄-rGO to adsorb onto the interfacial film, thus leading to a decrease in demulsification effect.Finally, the recyclability of Fe₃O₄-rGO greatly reduces the cost of demulsifier usage and also reduces the pollution and impact of demulsifier on the water and oil phases.This study not only provides a high-performance and recyclable demulsifier for the separation of polymer-containing aged oil, but also offers a new idea for the preparation of novel magnetic composite nanomaterials.更多还原