Triazoles as a class of multifunctional corrosion inhibitors. A review. Part I. 1,2,3-Benzotriazole and its derivatives. Copper, zinc and their alloys

This article presents an overview of the studies (2003-2018) on the adsorption of 1,2,3-benzotriazole (BTA) and its derivatives on copper, zinc and some of their alloys from aqueous solutions, and their corrosion inhibition capability in neutral and acidic media. It examines the effect of these organic corrosion inhibitors (CIs) on the formation of surface layers, their composition and the effectiveness of their protective action that were investigated by corrosion, electrochemical and other physicochemical methods. Considerable attention has been given to BTA itself, the wide range of corrosive media in which it can be an effective CI, an analysis of the reasons for its successful application in the practice of anticorrosion protection of copper and its alloys, as well as the new prospects of its usage and increasing its inhibition efficiency. At the same time, the drawbacks of BTA as a CI, including the sharp decrease in protective properties, up to their complete loss, in the presence of even small concentrations of H2S and sulfide ions and the relatively low efficiency in acid solutions were noted. The inhibition of corrosion of zinc and copper-zinc alloys by BTA has been discussed. It has been shown that the protection is based on the formation of sparingly soluble complexes of copper and zinc with BTA. Examples of improving the effectiveness of their protection with mixed CIs are given. The review notes the almost complete absence of studies of BTA derivatives for the protection of Zn, which could also be very useful for improving the corrosion protection not only of zinc but also galvanized steel.