Corrosion Inhibitory Behavior Study of Benzotriazole in Corrosive Environment

One of the most important methods to control the corrosion in various environments is the use of inhibitors such as nitrates and chromates. Finding alternative compounds for these compounds is very important for environmental reasons. Benzotriazoles and the family of azoles are one of these alternatives that are absorbed to the surface chemically by sharing of the lone pair of electrons of a nitrogen atom with an orbital metal which prevent dissolving and corrosion. In this review article, a summary of the studies on the inhibitory behavior of this chemical composition in different conditions such as acidic (hydrochloric acid and sulfuric acid) and basic environments is reported. Studies have shown that this compound has a very high inhibitory effect in all environments due to the ability to form metal complexes and insoluble monolayers (less than 50 angstroms) on the metal surface. This compound exhibits a mixed and anodic inhibitory behavior in acidic and alkaline environments, respectively. Increasing the concentration of this compound to an optimal level reduces the corrosion density and its excessive increase does not have an effect on reducing the corrosion rate. The presence of any impurities in the corrosive environment, due to the competition between benzotriazole molecules and impurities on absorption in the active sites of the metal, can have significant effects on its inhibitory efficiency.