The efficiency of protection of structural steel by cationic inhibitor under conditions of corrosion with bacterial sulfate reduction

Abstract

The effectiveness of protecting a structural steel by cationic inhibitor against biocorrosion caused by Desulfovibrio sp. М-4.1, Desulfomicrobium sp. TC 4, and sulfidogenic microbial communities was investigated by using gravimetric and electrochemical methods. The research showed that at a concentration of 1 g/l, the inhibitor offers greater protection to steel St3ps against Desulfomicrobium sp. TC 4 (up to 81.0%) than to Desulfovibrio sp. М-4.1 (up to 72.2%). The structure of the molecules of the inhibitor's compounds determines their ability to form a protective layer on the surface of the metal and exhibit antimicrobial action to sulfate-reducing bacteria and their satellites (iron-reducing bacteria). The inhibitor provides a high degree of protection (>92.9%) in microbial corrosion under the influence of sulfidogenic microbial communities. The cationic inhibitor was shown to have a greater effect on the electrochemical performance of the corrosion process for the biofilm form of sulfate-reducing bacteria than for the planktonic form.