Investigation on 2-mercaptobenzothiazole behavior as corrosion inhibitor for 316-stainless steel in acidic media

Purpose – The purpose of this paper is to describe the behavior of 2-mercaptobenzothiazole (MBT) on the corrosion of 316 stainless steel (SS) in acidic media and the mechanism of its action. Design/methodology/approach – The inhibitive effect of MBT towards the corrosion of 316 SS in acid solution is studied by means of weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy. The effect of inhibitor concentration and temperature against inhibitor action is investigated. Adsorption isotherm and adsorption mechanism are also discussed. Findings – MBT acts as inhibitor for this type of steel in acidic medium. This compound is mixed-type inhibitor and inhibition efficiency increased with increasing inhibitor concentration. MBT retards the rate of both anodic and cathodic corrosion reactions by adsorbing and forming a layer on the steel surface and the adsorption obeys Temkin adsorption isotherms. The inhibition efficiency is temperature dependence in the range from 25 to 65°C and some thermodynamic parameters were calculated and analyzed. Originality/value – The results shown in this paper are an insight to the understanding of the corrosion resistance and electrochemical behavior of 316 SS in the presence of MBT for future industrial applications and development. It is the first time that corrosion inhibition effects of MBT on 316 SS have been evaluated.