The universality of inhibitors is understood as their ability to inhibit several types of corrosion attack: hydrogen sulfide and carbon dioxide corrosion, hydrogen diffusion into metal, development of sulfate-reducing and other types of bacteria, negative impact on the mechanical properties of metals. Indicators of universalism of new inhibitor have been studied. Producer of the inhibiting compositions is Limited Liability Company «INCORGAZ» (S-Petersburg, Russia). The efficacy of the inhibitor in the concentration of 25 - 200 mg/L has been studied with respect to carbon steel in a highly mineralized chloride medium (pH= 6) and NACE medium (5 g/L NaCl, 0.25 g/L CH3COOH, pH =3.5) containing H2S (50-400 mg/L) and CO2 (1at) separately and together. The bactericidal properties of the inhibitor were studied with respect to sulfate-reducing bacteria in the Postgate medium. The investigations were carried out by the methods of linear polarization resistance, electrochemical impedance spectroscopy, gravimetry, potentiodynamic polarization. The protective effectiveness of the inhibitor reaches 80% in the presence of CO2 and 90% in hydrogen sulphide environments. The inhibitor repeatedly reduces the number of sulfate-reducing bacteria and the production of biogenic hydrogen sulfide and inhibits the diffusion of hydrogen into steel.

No abstract

Using the methods of gravimetry, potentiodynamic polarization, and impedance spectroscopy, the protective effectiveness of the inhibitory composition INCORGAZ-111 with respect to hydrogen sulfide corrosion of carbon steel St3 in NACE and Samotlor oil field model stratum waters has been studied. Surface coverage is determined on the basis of the electric double layer capacity in presence of the inhibitor. Its adsorption is interpreted using the polylogarithmic isotherm with a big energy gradient of adsorption centers, that indicates linear energy heterogeneity of the surface. The constants of adsorption equilibrium, the energy gradient and the energy dispersion of adsorption centers as well as adsorption free energy were calculated.

No abstract