Elemental chlorine-free conversion of waste HCl liquor by oxidation and concentration to form aqueous ferric chloride solution

摘要

A process for treating waste HCl pickle liquor by oxidation to form aqueous ferric chloride (FeCl₃) without using chlorine gas. In accordance with the process, heavy metals and other impurities are removed from the waste HCl pickle liquor, as desired. The ferrous chloride-containing solution is oxidized in the presence of a stoichiometric amount of HCl to form aqueous ferric chloride solution. The resulting solution, which is relatively dilute, preferably is concentrated, typically by evaporation. Ferric chloride solution is useful, for example, for water treatment.