EFFECT OF OXYGEN AND OXYGEN-CONTAINING OXIDANTS ON THE RATE OF ACTIVEDISSOLUTION OF METALS IN ACID-MEDIA

Generalization of die experimental data is given and a probable mechan ism is considered for the interplay between the rates of the electrode processes that take place during the self-dissolution of metals (Fe, Cr, Zn, Sn) in moderately acid electrolytes in the presence of oxygen and oxygen-containing oxidants (H2O2, Na2Cr2O7, NaNO2, NaNO3, Na2SO3, etc.). It is shown that the oxidants can markedly raise the rate of th e anodic dissolution of metals at a constant potential. In so doing, t he accelerating action of the oxidants depends on the metal dissolutio n mechanism, the pH value and anion composition of the electrolyte, an d the concentration and character of the oxidant The data obtained con firms the involvement of final and intermediate products of oxidant re duction in the anodic process.