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

Abstract

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

Effect of Al2O3 on the Reduction of Hematite (Fe2O3)

“…Among the mineral phases the hematite phase has the lowest hardness and the lowest fracture toughness, and it decreases with increasing Al 2 O 3 content [18]. Therefore, when the reduction expansion of α-Fe 2 O 3 produces cracks, it tends to diffuse and extend in the hematite phase with high Al 2 O 3 content, which increases the RDI of sintered ore [19].…”