An Electrochemical Impedance Spectroscopy Study of Inhibition Effect of SONKOR Composition on Hydrogen Sulfide Corrosion of Carbon Steel

The protective properties of five corrosion inhibitors of SONKOR series on low-carbon steel St20 in a 1 M HCl with the addition of 0–0.6 g/L H 2 S have been studied by the electrochemical impedance spectroscopy method. The series of changes in the adsorbability of corrosion inhibitors on a steel electrode in 1 M HCl and 1 M HCl + 0.6 g/L H 2 S solutions have been established. Equivalent electrical circuits have been proposed for various media. It is shown that some elements of equivalent circuits are associated with the kinetics of inhibitors adsorption.