Separation and recovery of copper from zinc leach liquor by solvent extraction using Acorga M5640

The present study deals with the separation of copper from zinc leach liquor obtained by acidic ferric sulphate leaching of an industrial sphalerite concentrate. The leach liquor was subjected to copper extraction using Acorga M5640 and its formulation was also tried to be modified with isotridecanol to enhance the overall process. The effect of pH and presence of isotridecanol on the separation of copper was examined. Also, the effect of this modifier on the equilibrium and kinetics of copper extraction was investigated. The co-extraction of iron was not found very significant and less than 10 mg/L was attained in the loaded 10% (v/v) Acorga M5640 at pH 1.35. The presence of alcohol did not boost the net copper transfer significantly, despite the rejection over iron was slightly favoured. The kinetics of copper extraction from zinc leach liquor using Acorga M5640 was very fast, even in the presence of 2.5% (v/v) isotridecanol.

Research highlights
► Cu(II) is successfully separated from real leach liquor at pH 1.35.
► Isotridecanol enhances stripping step but hinders loading of Cu with Acorga M5640.
► Isotridecanol can increment Cu net transfer and rejection ratio over Fe(III).
► Approach to equilibrium exceeds 99% in 60 s (10% extractant, 0–2.5% isotridecanol).