Ultra high purification of copper chloride solutions by anion exchange

On the basis of anion-exchange equilibrium data in hydrochloric acid solutions, elements were classified into three groups by their separation from copper. The Cu(I) chloro-complex species are fixed in the resin and the non-absorbed (Class I) impurities are eliminated. This is followed by in situ oxidation and elution of copper in the Cu(II) state, leaving the strongly absorbed (Class II) elements behind in the column. Impurities of varying absorbabilities (Class III) could also be separated by an appropriate elution technique. The experimental elution curves of the characteristic elements proved that the method is capable of eliminating practically all the impurities from copper. Application of the combined anion-exchange purification procedure could provide a relative degree of purification of 1000, removing more than 99.9% of the impurities, while the copper yield was kept above 70%.