Purification of copper chloride solution by anion exchange for the preparation of ultra high purity copper

The significant potential advantages offered by the formation of chloro-complexes and the anion exchange separation of copper and the metallic impurities were intended to be exploited in order to facilitate the subsequent extraction of ultra-high purity copper. The adsorbabilities of the characteristic elements from hydrochloric acid solutions on a 'strong-base' quaternary amine anion-exchange resin were studied by the equilibrating method. On the basis of the distribution data, a special process using both the Cu(I) and Cu(II) states of copper was designed for the most complete possible eliminations of all the metallic impurities. Copper is initially fixed in monovalent state on the resin, followed by oxidation and selective elution in the divalent form. Under properly selected conditions, the impurities are efficiently removed in both steps. The proposed procedure was tested on a laboratory scale, and the electrowinning of the metal from the resulting purified copper chloride solution proved feasible.