Temperature and pH effect on composition of a precipitate formed in FeSO4–H2O–H+/OH−–H2O2 system

There are investigated regularities of phase formation during oxidation of iron(II) sulfate in aqueous solutions and/or iron(II) hydroxide suspensions by hydrogen peroxide under quasi-stationary conditions. There are found areas of predominant formation of “ferrihydrite”, Fe3O4, α-, γ- and δ-FeOOH phases in pHO–temperature coordinate system. There is analyzed a chemical nature of “ferrihydrite”, and pH0 and temperature effect on chemical, phase and disperse precipitate composition.