Synthesis and properties of nonylphenol-substituted dodecyl sulfonate

Abstract

ABSTRACTNonylphenol-substituted dodecyl sulfonate (C12-NPAS) was synthesized via sulfonation-alkylation-neutralization using 1-dodecene, SO3, and nonylphenol as raw materials. The properties such as surface tension, interfacial tension (IFT), wettability, foam properties, and salinity tolerance of C12-NPAS were systematically investigated. The results show that the critical micelle concentration (CMC) of C12-NPAS was 0.22 mmol · L−1 and the surface tension at the CMC (γCMC) of C12-NPAS was 29.4 mN/m. When compared with the traditional surfactants sodium dodecyl benzene sulfonate (SDBS), sodium dodecyl sulfate (SDS), and linear alkylbenzene sulfonate (LAS), the surface properties of C12-NPAS were found to be superior. The IFT between Daqing crude oil and a weak-base alkaline/surfactant/polymer (ASP) oil flooding system containing 0.1 wt% of C12-NPAS can reach an ultralow level of 2.79 × 10−3 mN/m, which was lower than that found for the traditional surfactant heavy alkylbenzene sulfonate (HABS). The salinity and hardness tolerance of C12-NPAS were much stronger than those found for conventional surfactants, petroleum sulfonate, and LAS. C12-NPAS also shows improved wetting performance, foamability, and foam stability.