PRODUCTION OF IRON ORTHOPHOSPHATE

Abstract Production of iron orthophosphateA process for the production of iron (III) orthophosphate of the general formula FePO4 x nH20 (n < 2.5) in whichan aqueous solution containing Fe2+ ions is produced in that oxidic iron (II), iron (III) or mixed iron (II, III) compounds selected from hydroxides, oxides, oxide hydroxides, oxide hydrates, carbonates and hydroxide carbonates, together with elementary iron, are introduced into a phosphoric acid-bearing aqueous medium, and Fe2+ ions are dissolved and Fe3+ is reacted with elementary Fe (in a comproportionation reaction) to give Fe2+,solids are separated from the phosphoric-acid aqueous Fe2+ solution, andan oxidation agent is added to the phosphoric-acid aqueous Fe2± solution to oxidise iron (II) in the solution and iron (III) orthophosphate of the general formula FePO4 x nH20 precipitates. Figure 2a