Effect of Natural Leaf-derived Surfactants on Wettability Alteration and Interfacial Tension Reduction in Water-oil System: EOR Application

In this study, two types of plants based natural cationic surfactants, named Mulberry and Henna are introduced and the application of these natural surfactants in wettability alteration of reservoir rock and reducing the interfacial tension of water-oil system is investigated. For this purpose, two natural-based surfactants were extracted from the leaves of the trees of addressed plants and then the interfacial tension (IFT) values between oil and natural surfactant solution and also the contact angle values between natural surfactant solution and rock sample were measured. The results demonstrated that Mulberry extract was able to lower the interfacial tension between oil and distilled water from 43.9 to 4.01 mN/m, while Henna extract could reduce the IFT from 43.9 to 3.05 mN/m. These natural surfactants were also able to reduce the contact angle of rock/fluid system which shows the wettability is altering to water wet system and so it may increase recovery factor by reducing residual oil saturation and Henna extract could reduce the contact angle more than that of Mulberry leaf extract. According to these results in addition to the low price of generating natural surfactants, the feasibility of using these kinds of surfactants in future oil recovery processes is of major concern.