Process for reducing iron in phosphoric acid solution
AssigneeHoechst Aktiengesellschaft
InventorsKlaus Schrodter, Klaus Lehr
Life of this patent
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Abstract
Iron contained in phosphoric acid solution is reduced from the trivalent to the bivalent oxidation stage. To this end, red phosphorus is used as the reductant and the reduction is effected in the presence of copper.
Claims9
A process for reducing iron from the trivalent to bivalent oxidation stage with the aid of a reductant, the iron being present in phosphoric acid solution, which comprises using red phosphorus as the reductant and effecting the reduction in the presence of at least 5 ppm of copper, based on the weight of the solution at temperatures within the range of 10.degree. to 90.degree. C. by keeping the red phosphorus in contact with the iron-containing phosphoric acid solution over a period at least necessary for the reduction of iron.
Dependencies are inferred from the claim text.