Experimental Study: Anionic-Zwitterionic Surfactant Performance Enhancement Using Alkali and Cosolvent BACHELOR THESIS Arief Maulana 12218018 Submitted as partial fulfillment of the requirements for the degree of BACHELOR OF ENGINEERING in Petroleum Engineering study program PETROLEUM ENGINEERING STUDY PROGRAM FACULTY OF MINING AND PETROLEUM ENGINEERING INSTITUT TEKNOLOGI BANDUNG 2023 EXPERIMENTAL STUDY: ANIONIC-ZWITTERIONIC SURFACTANT PERFORMANCE ENHANCEMENT USING ALKALI AND COSOLVENT BACHELOR THESIS ARIEF MAULANA 12218018 Submitted as partial fulfillment of the requirements for the degree of BACHELOR OF ENGINEERING in Petroleum Engineering study program Approved by: Thesis Adviser, Ivan Kurnia, S.T., M.Sc., Ph.D. NIP 198812052015041004 1 Experimental Study: Anionic-Zwitterionic Surfactant Performance Enhancement Using Alkali and Cosolvent Arief Maulana* and Ivan Kurnia** Copyright 2023, Institut Teknologi Bandung Abstract Research about surfactant application as one of the enhanced oil recovery methods to increase the field recovery factor has been intensified recently. One of the objectives of surfactant application is to reduce Interfacial Tension (IFT) between brine and crude oil. Previous research shows that surfactant formulation with addition of alkaline could boost their performance in lowering IFT value compared to using surfactant only. In this study, several experiments will be carried out to monitor the effect of alkaline addition in surfactant, and to prevent gel precipitation, cosolvent will moreover be added in this formulation process. This study uses surfactant mixture of anionic/zwitterionic AR-M/MA-AO14 and AR-L/MA-AO14 with 0.5% concentration, Sodium Carbonate as alkaline, and Isopropyl Alcohol (IPA) as cosolvent. The experiment starts with formulation by mixing surfactant, cosolvent, and various concentrations of alkaline to screen aqueous stability. A salinity scan test using pipettes is performed to see phase behavior of surfactant-alkaline-cosolvent mixture with crude oil. Spinning drop tensiometer is used to determine each mixture's IFT value. From aqueous stability test mixture of AR-M/MA- AO14 yield a clear solution, while mixture of AR-L/MA-AO14 yield a cloudy solution, therefore alcohol concentration is added to 2% to improve solubility. Salinity scan result shows that most of the mixtures of AR- M/MA-AO14 form oil-in-water microemulsion, while AR-L/MA-AO14 mostly form bicontinuous oil-water microemulsion for both 0.5% and 2% alcohol concentration. Tensiometer gave the conclusion of AR-L/MA- AO14 reached lowest IFT value at 8.74 x 10 -4 mN/m when using 0.5% alkali, while AR-M/MA-AO14 reached lowest IFT value 2.21 x 10 -3 mN/m at maximum 2% alkali concentration. This study is part of the optimization process of EOR method and the result shows that alkaline with cosolvent could be used to enhance surfactant performance. Keywords: Surfactant, Alkaline, Cosolvent, Interfacial Tension, Phase Behavior Test, Microemulsion. Sari Penelitian mengenai surfaktan sebagai salah satu metode peningkatan perolehan minyak sangat digencarkan belakangan ini. Salah satu tujuan aplikasi surfaktan adalah menurunkan Interfacial Tension (IFT) antara brine dan minyak mentah. Beberapa penelitian menunjukkan bahwa formulasi surfaktan dengan penambahan alkali dapat meningkatkan kinerjanya dalam menurunkan nilai IFT dibandingkan dengan hanya menggunakan surfaktan saja. Pada penelitian ini akan dilakukan beberapa percobaan untuk memantau pengaruh penambahan alkali pada surfaktan, dan untuk mencegah pengendapan gel, kosolven juga akan ditambahkan dalam proses formulasi ini. Penelitian ini akan menggunakan campuran surfaktan anionik/zwitterionik AR-M/MA-AO14 dan AR-L/MA-AO14 dengan konsentrasi 0,5%, Natrium Karbonat sebagai alkali, dan Isopropil Alkohol (IPA) sebagai kosolven. Eksperimen dimulai dengan mencampurkan surfaktan, kosolven, dan berbagai konsentrasi alkali untuk memantau stabilitas larutan.