Effect of some organic surfactants on the corrosion behavior of low-carbon steel in sulfuric acid solution

The corrosion of 08PS low-carbon steel in 2 M H2SO4 in the presence of cationic (alkylbenzyldimethylammonium chloride (Catamin AB)), amphoteric (cocamidopropyl betaine (CAPB)), anionic (sodium lauroyl sarcosinate (SLS), sodium oleoyl sarcosinate (SOS), sodium dodecylbenzenesulfonate (SDBS)), and non-ionic surfactants (indirect material OP-10) was studied.Only Catamin AB in individual form is capable of providing effective protection of steel in 2 M H2SO4 solutions (t = 60C).When creating binary and threecomponent composite corrosion inhibitors (CIs) based on the surfactants under study, in some cases it is possible to achieve effective protection of steel in 2 M H2SO4 within a wide temperature range.Among the composite CIs under study, one should note the (5 mM Catamin AB + 0.5 mM KI) and (1 mM Catamin AB + 4 mM hexamethylenetetramine + 0.5 mM KI) formulations that significantly inhibit steel corrosion in 2 M H2SO4 at temperatures up to 95C inclusive.Instead of a binary formulation of CIs (surfactant + KNCS or KI) it is sometimes expedient to utilize a similar three-component CI containing a surfactant + hexamethylenetetramine + KNCS or KI for the protection of steel in H2SO4 solutions.In spite of an insignificant acceleration of metal corrosion in their presence compared with the binary mixture, three-component CIs make it possible to significantly reduce the consumption of surfactants.