The Effect of Stoichiometry of Iron (II) and (III) and Magnetite Oxides on the Kinetic Regularities of their Dissolution in Orthophosphoric Acid Containing Fe (II) and Fe (III) Ions

The kinetics of dissolution of iron oxides FeO, α-Fe₂O₃ and Fe₃O₄ in orthophosphoric acid, including those containing additions of Fe (II) and Fe (III) ions (in the form of perchlorates), has been studied. The values of the stationary potential in the magnetite electrode system--solutions of orthophosphoric acid, including those containing additions of Fe (II) and Fe (III) ions are determined. The dissolution of Fe₃O₄ in orthophosphoric acid has been studied and described. Based on the experimental results, it was established that the stimulating and inhibitory effect of Fe (II) and Fe (III) ions is related to their effect on the value of the potential at the boundary of the iron oxide phases/electrolyte solution. The orders of reactions for ions Fe (II), Fe (III) and H₃PO₄ are determined

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