Emulgin as an Inhibitor of Corrosion and Hydrogenation of Carbon Steel in Weakly Acidic H2S-Containing Solutions

The protection effect of emulgin (a technological mixture of some primary and secondary aliphatic amines) in concentrations of 0.078 to 0.625 mmol/l from acid, carbon dioxide, and hydrogen sulfide corrosion and hydrogenation of carbon steel St3 was studied. In a 0.005–0.05 M solution of HCl saturated with hydrogen sulfide, the protective value was 97%, no local damage being observed. At higher concentrations of HCl and H2S, the anodic reaction is inhibited more effectively. The simultaneous presence of H2S and CO2 produces virtually the same (or only slightly reduced) effect. Under optimum conditions, steel hydrogenation is suppressed almost completely, especially at high concentrations of HCl and H2S and at elevated temperatures.