Search

Amine-surfactant can be converted to be cationic surfactant in water solution saturated with CO 2 , which can enhance their foaming ability and foam stability, and the foaming ability can be switched off or on by CO 2 or replacing with N 2 with heating, so the amine-surfactants have great potential for smart mobility control to gas channeling during CO 2 flooding. In this study, three alkyl propyl dimethylamines with different carbon chain length (R = 11, 17 and 22, named as UC 11 AMPM, UC 17 AMPM, and UC 22 AMPM, respectively), were investigated as CO 2 responsive foam agent, and their foam performance under static and dynamic condition was tested up to 130 °C and 10.5 MPa using a visualized foam meter and a sand-pack flooding setup. The influence of carbon chain length on bulk solution viscosity, surface activity, foaming ability, and foam quality on bulk foam stability were measured and analyzed. The experimental results indicate that the three amine surfactants all demonstrate well CO 2 responsibility and CO 2 foaming ability, and show well switchable by CO 2 and N 2 at high temperature and high pressure (HTHP) condition. With the carbon chain length increasing, the surfactant shows higher absorption on the foam films, and bulk solution has a higher viscosity, which can decrease de-foam velocity and enhance the foam stability, as a result, the surfactant shows higher mobility control ability. • The CO 2 foam performance of three amine surfactants were tested at HTHP conditions. • The influence of carbon chain length on foam performance, bulk viscosity, surface active and foam quality was analyzed. • Alkyl propyl dimethylamines have well mobility control ability to CO 2 at high temperature-tolerance (up to 130 °C). [ABSTRACT FROM AUTHOR]