Functional oil-displacement materials: current advances and future perspectives

With the increasing global energy demand, enhancing the oil extraction technology is currently critical. The existing enhanced oil recovery technologies based on chemical flooding and traditional oil-displacement materials continue to present defects, which include large adsorption loss of the chemical oil-displacement agent in the injected reservoir and blind use of chemical agents due to insufficient understanding of the reservoir flow path. Such defects significantly limit the application of traditional oil displacement materials. Therefore, many oil-displacement materials with additional functions have recently been developed. In order to better understand the application of these functional oil displacement materials, this paper summarizes the applications and mechanisms of oil-displacement materials with controlled release, tracers, and oil recovery functions. These functional oil-displacement materials are suitable for tertiary oil recovery and can be used in low-permeability reservoirs. Moreover, magnetically recovered oil-displacement materials can be recycled for environmental protection and sustainability. Additionally, we discuss the challenges and future perspectives related to this field.