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Terbatas Suharsiyah

The application of ASP at high salinity is more challenging because of the frequent precipitation in the solution. In several studies carried out, cosolvent was used to help keep the solution in a single-phase condition. In this study, the performance of chemical EOR (Enhanced Oil Recovery) which consists of a mixture of zwitterionic and anionic surfactants will be shown without the help of a cosolvent. An aqueous stability test was conducted to see the stability of the solution under certain conditions. In addition, phase behavior is also carried out to see the formed microemulsion and determine the optimum salinity. And at the end, there is an IFT measurement that is carried out with a spinning drop. From the results obtained, the mixture of zwitterionic surfactant Macat Ultra CDO with anionic surfactant Aristonate-M and Aristonate-L showed a lower IFT value than the IFT value of each surfactant before mixing. In addition, in the phase behavior, a type III microemulsion was formed at 2.5% salinity. This shows that there is a synergy between the surfactants Macat Ultra CDO with Aristonate-M and Aristonate-L. These results can be an alternative as a consideration that can be used in the application of EOR Chemical. Keywords: Anionic Surfactant, Zwitterionic Surfactant, Aqueous Stability, Microemulsion, Interfacial Tension, Phase Behavior Test