Method of recovering iodine
AssigneeSolvay Fluor und Derivate GmbH
InventorsRalf Herkelmann, Werner Rudolph, Dirk Seffer
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Abstract
A method for recovering iodine from a composition containing iodine and/or iodide in which any iodine present is first reduced to iodide, the iodide is then separated from solution by selective anion exchange absorption, the separated iodide is eluted from the exchanger, the iodide-containing eluate solution is treated with a cation exchanger, H.sub.2 O.sub.2 and H.sub.2 SO.sub.4 are then added to the remaining solution, and the resulting iodine is precipitated and may be separated out in crystalline form. The method is also particularly suitable for separating iodine from solutions which contain organic constituents such as nitrogen-containing organic compounds.
Claims9
A method for recovering iodine from an aqueous solution containing iodine, iodide or mixtures of iodine and iodide, said method comprising the steps of:
- if iodine is present, reducing the iodine to iodide;
- separating the iodide from said aqueous solution by ion exchange absorption with an iodide-selective anion exchanger;
- eluting iodide from the anion exchanger by treating the ion exchanger with lye to obtain an iodide-containing eluate solution;
- treating the iodide-containing eluate solution with a cation exchanger until the solution has a pH of less than 4;
- oxidizing the iodide in the treated solution with H.sub.2 O.sub.2 to form iodine, and
- isolating the resulting iodine.
Dependencies are inferred from the claim text.