Novel Poly(catechol-amine)-Modified Graphene Oxide Nanosheets for Enhancing Conventional Heavy Oil Recovery

In this study, novel poly(catechol-amine)-modified graphene oxide (PLCA-RGO) nanosheets with high interfacial activity and viscosity reduction ability were prepared to enhance conventional heavy oil recovery. Scanning electron microscopy (SEM), Fourier-transform infrared, thermogravimetric analysis, and other techniques were used to analyze the morphology, thermal stability, chemical composition, viscosity reduction, oil recovery ability of heavy oil, and the mechanism of viscosity reduction. The results show that PLCA-RGO can form stable O/W emulsions, which have the ability to reduce oil–water interfacial tension and change wettability, as well as static and dynamic viscosity reduction ability of heavy oil. DLS and asphaltene morphology analysis before and after viscosity reduction showed that PLCA-RGO not only had the ability to stabilize the emulsion but also had a certain ability to disperse asphaltene aggregates. In addition, the PLCA-RGO + HPAM composite system showed a better heavy oil displacement ability. Therefore, the proposed PLCA-RGO may be a potential oil displacement agent for heavy oil.