The influence of dissolved molecular oxygen on the corrosion of metals in aqueous acid solutions. Review

This review discusses the current state of research in the field of corrosion of metals in aqueous solutions of acids containing molecular oxygen, as well as various issues of inhibitory protection of metals in such acidic environments.Thermodynamic aspects of metal corrosion in aqueous media containing dissolved O 2 are discussed.Reference data on the physicochemical properties of O 2 present in acidic aqueous media is presented.Modern views on the mechanism of O 2 reduction on metals are discussed.Corrosion of a metal in such an acid solution containing O 2 generally occurs as a result of its parallel reactions of interaction with the acid itself and O 2 molecules.In the case of metals with E  (Me z+ /Me)>0 V, the only possible reaction is interaction with O 2 .A specific feature of corrosion occurring with oxygen depolarization is its diffusion control, which makes this process very sensitive to the nature of convection of the aggressive environment.An increase in the rate of corrosion of metals is caused by an increase in the O 2 content in the solution and the transition from a static environment to a dynamic one.The presence of molecular O 2 in acid solutions reduces the effectiveness of metal protection with corrosion inhibitors, in comparison with similar oxygen-free environments.In inhibited environments containing O 2 , the sensitivity of metal corrosion to the parameters of solution convection remains.The bibliography includes 109 references.