▎ 摘　　要

Currently, thermal oil recovery methods are commonly applied to heavy oil development. Microwave heating is an effective recovery method and has the advantages of rapid heat transfer, volumetric heating, and selective heating. In the process of using microwaves to extract heavy oil, catalyst-assisted microwaves for oil viscosity reduction are adopted. In this study, magnetic graphene oxide (MGO) with a good load is prepared using a charge self-assembly method. The MGO is then characterized using scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Next, the dispersibility of MGO in water with increasing microwave treatment time is studied using ultraviolet spectrometry. Finally, using microwaves, the heavy oil viscosity reduction effect of MGO and the oil displacement effect of MGO fluid are tested. The results revealed that MGO is a catalyst supported by ferroferric oxide nanoparticles (denoted as nano-Fe3O4) on graphene oxide. Its loadability and dispersibility in water are good. With an increase in the radiation duration of the microwaves, its dispersibility in water deteriorates and magnetic-reduced graphene oxide (MRGO) forms, which exhibits lipophilicity and better microwave absorption performance than MGO. However, MGO performs well in heavy oil viscosity reduction using auxiliary microwaves. The viscosity reduction rate reached 43.61% after 10 min of microwave treatment when adding a hydrogen donor, and the heavy oil was modified to increase the content of light components. Furthermore, MGO fluid flooding was found to have a higher recovery efficiency under microwave irradiation compared with conventional water flooding. The thermal stress generated by the microwaves caused the oil and water to retransport in the porous medium, blocking some of the turbulent channels, which increased the swept volume of the subsequent displacement. In addition, the lipophilic MRGO produced under microwave treatment approached the oil spontaneously and, together with the loaded Fe3O4, reacted on the oil to reduce its viscosity. This was beneficial for the separation and shedding of the oil from the attachment. Therefore, MGO-assisted microwave treatment can potentially be used to enhance oil recovery.