| abstract |
Oxygen and metallic iron are produced from an iron oxide-containing mineral, such as ilmenite, by extracting iron from the mineral with hydrochloric acid, separating solid residue from the resulting solution and drying same, electrolyzing the separated, iron chloride-containing solution to produce electrolytic iron and chlorine gas, combining the chlorine gas with water recovered from the drying and/or iron chloride-containing solution electrolysis steps of regenerate hydrochloric acid and recycling the hydrochloric acid to the extraction step. In an alternate embodiment, the chlorine gas is reacted with recovered water in the presence of a catalyst to produce hydrochloric acid which is recycled to the extraction step, thereby eliminating the need for water electrolysis and a separate hydrochloric acid regeneration step. In another alternate embodiment, electrolysis of the iron chloride-containing solution is operated to produce oxygen instead of chlorine gas at the anode and hydrochloric acid is generated concurrently with plating of iron at the cathode. This hydrochloric acid is recycled to the extraction step, thereby eliminating the need for water electrolysis and a separate hydrochloric acid regeneration step. |