A study on zinc recovery from leach solutions using Ionquest 801 and its mixture with D2EHPA

Abstract

Zinc recovery by solvent extraction with D2EHPA from its leach solutions has been successfully commercialised. As Fe(III) is strongly extracted by D2EHPA, 6M HCl is employed in the process to remove it in the organic bleed solution. The use of HCl complicates the process because extra process must be conducted to regenerate the HCl. In order to possibly avoid the use of HCl, zinc extraction and separation from impurities using Ionquest 801 and its mixtures with D2EHPA were studied. Zinc extraction with Ionquest 801 is lower than that with D2EHPA. However, the stripping of Fe(III) from the Ionquest 801 system using 4M H2SO4 is more effective than that from the D2EHPA system with 6M HCl. Therefore the use of HCl could be avoided leading to a simplified process. The application of the mixture of Ionquest 801 and D2EHPA for zinc recovery from its leach solution was also discussed.