The Interfacial Tension Between Cationic Gemini Surfactant Solution and Crude Oil

The effects of the hydrocarbon chains and spacer groups of gemini surfactants, salt, temperature, and polymer on the interfacial tension of crude oil-water mixtures were investigated in this paper. The length of the alkyl chain is a major factor affecting the properties of a gemini surfactant, and the spacer group is also an important factor influencing the surfactant properties. The addition of salt results in a great decrease in the CMC and favors the reduction of interfacial tension, which shows that a gemini surfactant has a good synergism with salt. Variation in temperature will affect the dynamic and equilibrium interfacial tension, and increasing the temperature can shorten the time to reach the equilibrium and decrease the equilibrium interfacial tension in the range of experimental temperatures. With the addition of polyacrylamide (PAM), it takes longer to reach equilibrium, but this has little effect on the value of equilibrium interfacial tension.