Modeling of extraction of copper and zinc from their mixtures in acidic chloride solutions

Extraction of copper(II) and zinc(II) present alone and in mixtures of various mole ratios from acidic chloride solutions was studied. The system containing high concentrations of hydrogen and chloride ions was considered. Kelex 100 with decanol as modifier was used as a bifunctional extractant. The chemical model, which takes into account the extraction of ion pairs and chelates, protonation of the reagent and the extraction of hydrochloric acid, was proposed and verified. The model agrees well both with the experimental results obtained for the systems containing individual metal ions and their mixtures. The model permits to estimate the contents of species present in the aqueous and organic phases. It also allows to make some extrapolation. (authors)