Investigation of the Corrosion Inhibition Efficiency on X65 Steel of Surfactant Mixtures of Alkyl Benzyl Dimethyl Ammonium Chlorides

The corrosion inhibition on X65 steel of a series of alkyl benzyl dimethyl ammonium (CnBDMAC) chloride surfactants was studied. The effects of surfactant concentration, hydrocarbon chain length, temperature, and salinity on the surfactant properties and inhibition efficiency were evaluated theoretically and experimentally. The distribution of surfactants among oil, aqueous phase, and steel surface was studied. The partitioning properties between oil and aqueous phase of the single surfactant/mixtures were evaluated using mass spectrometer. The surface tension was measured to determine critical micelle concentrations (CMC) and adsorption isotherms at the air-water surface. The inhibition efficiency was studied by linear polarization, electrochemical impedance spectroscopy (EIS), and Tafel slope method. Results are presented to show the inhibition effect dependence on the above mentioned factors. Mechanism behind the corrosion inhibition was discussed.