Perpustakaan Digital ITB

Chemical enhanced oil recovery is term referring to tertiary recovery of oil recovery operations using chemicals to displace additional oil after the secondary recovery process became uneconomical. Surfactant is necessary for reducing the IFT value that improves the microscopic displacement. There are thousands combination that could be used for discovering the highest-performance surfactant for reducing IFT. This study is focused on formulating the highperformance surfactants from combination between zwitterionic and anionic surfactants and the co-solvent addition (isopropyl alcohol). In this paper, there is a mixture that shows the form of better microemulsion than other mixtures of zwitterionic and anionic surfactants at surfactant total concentration of 0.5wt% surfactant in phase behavior test. The addition of cosolvent (isopropyl alcohol) at 0.3% of salinity system make the mixture form a middle-phase microemulsion and decreases the viscosity. From the IFT measurement using spinning-drop method, the mixture shows optimal salinity is at 2.5% of NaCl. This result shows that the addition of co-solvent has a vital role in stabilizing aqueous stability of surfactants mixture and reducing IFT value between oil and surfactants solution.