A Refined Scheme of the Mechanism of Iron Anodic Dissolution in Acidic Sulfate Solutions

A refined scheme of iron anodic dissolution in acidic sulfate solution, in which Fe^sub 0^ is oxidized to Fe^sup +^ in stages, is proposed. The first stage consists in chemisorption of H^sub 2^O molecules with participation of SO^sub 4^^sup 2-^ anions; the degree of the participation x [asymptotically =] 0.5 per a water molecule. This stage produces adsorbed OH groups (Fe(OH)^sub ads^), which, as a result of their interaction with sulfate anions, form an adsorption complex Fe((OH)SO^sub 4^^sup 2-^^sub ads^. The schemes of oxidation of Fe^sup +^ to Fe^sup 2+^ do not differ from conventional ones. The scheme put forward agrees with the literature data on the kinetics of iron dissolution under steady-state conditions.[PUBLICATION ABSTRACT]