Research on a synergistic formula of anionic and betaine type surfactants for natural gas fields

Abstract To further improve the foaming properties, foam stability, salt and temperature resistance, betaine surfactants were combined with sodium dodecyl sulphate-derived multifunctional surfactants synthesized in laboratory. Sodium dodecyl sulphate-derived multifunctional surfactants (HSDS) was synthesized and the changes in performance before and after the addition of hexadecyl betaine (HB) to hydroxymethylated sodium dodecyl sulfate were comprehensively compared by carrying out experiments such as such as measuring foam volume and surface tension. The foaming volume of hexadecyl betaine (HB) compounded with HSDS-4 is found to reach 475 mL with a half-life of 7.72 min. The temperature resistance test shows that the foam volume of HS-4 at 70 °C is 22.9 mL. At a salt content of 200 g L−1, the foam volume of HS-4 is still 355 mL with a half-life of 6.13 min. Finally, the microstructure of the foams produced by the different compounds was measured. The foam produced by HS-4 had the lowest defoaming rate compared to the other compounds. The effectiveness of the compounded product in improving the recovery rate is shown, providing support for the further innovation and utility of this technology.