Transformations

This chapter contains sections titled: Introduction Thermal transformations General Goethite to hematite Lepidocrocite to maghemite or hematite Akaganéite and schwertmannite to hematite δ-FeOOH and feroxyhyte to hematite Ferrihydrite to hematite Interconversions between maghemite and hematite Via solution transformations Lepidocrocite to goethite/hematite Akaganéite to goethite/hematite Schwertmannite to goethite Maghemite and goethite to hematite Ferrihydrite to other Fe oxides Rate of transformation Hematite versus goethite formation Mechanism of transformation Effect of foreign compounds Oxidative and reductive transformations Oxidation of magnetite to maghemite or hematite Reduction of FeIII oxides to magnetite Reduction of iron ores to iron Interaction of iron oxides with other metal oxides and carbonates