Model Study of Enhanced Oil Recovery by Flooding with Aqueous Solutions of Different Surfactants: How the Surface Chemical Properties of the Surfactants Relate to the Amount of Oil Recovered

The main aim of this work is to establish how the-fraction of oil recovered from an oil-filled calcite powder packed column by injection of,aqueous surfactant solution depends on the phase behavior and surface chemical properties Of the surfactant system., We have measured the phase behavior, the adsorption of surfactant to the oil water, calcite water, and calcite oil interfaces, tensions, and contact angles for anionic, cationic, and nonionic surfactant/oil/aqueous phase systems. We show how the measured surface chemical properties can be used to-approximately predict the fraction of oil recovered as, a function Of the volume and concentration of the surfactant solutions injected into the column. Measured and calculated plots of %oil recovery versus surfactant concentration show reasonably good agreement for the different surfactant systems. The experimentally validated model for oil recovery provides a sound basis for the rational selection of surfactant type and concentration to achieve maximum oil recovery based on laboratory measurements of the surface chemical properties of candidate surfactants.