Study on graphene-based emulsions as oil displacement agent.

In this study, graphene oxide (GO) was prepared by the improved Hummers method, and a synergistically stabilized emulsion of GO and emulsifier was formulated. The best emulsion formula obtained by Response Surface Methodology consists of 1.39? GO, and 2.92? OP-10; the water-oil ratio is 4:6, achieving an emulsion index of 92.83%. The emulsion still maintained good stability under high temperature and high salt conditions, meeting the environmental requirements of medium and low permeability reservoirs. For injected water flooding, emulsion flooding could increase the oil recovery by 15.41%. [ABSTRACT FROM AUTHOR]