MUKANDA MUKUNA Trésor1,5, KAPYA TSHINANGI Fabrice2, MANENE NGOIE Francine3,4, KABUNDA TSHIBANGU Henri4, ZEKA MUJINGA Léon4,5*

Impact of Washing Leach Solutions Using SHELLSOL 2325 Diluent on Copper Solvent Extraction at Luita plants in D.R. Congo.

The significance of pre-treatment by washing using Shellsol 2325 diluent was investigated on heap leach solutions of oxidized ores from Luita plants. These solutions contained as metal of value 14 g/L Cu and as impurities to be removed by washing 487 ppm of dissolved silica and 550 ppm of suspended solids. The washed solutions were then treated to solvent extraction. The results showed that increasing the PO/PA ratio and the stirring speed led to the increase in the washing impurity removal efficiency with a minimum removal efficiency of 57%. The solutions washed in organic continuity led to lower values of phase disengagement time during copper extraction than those performed in aqueous continuity. By pre-treating the solutions by washing in organic continuity in this way, the washing showed a positive effect regardless of the continuity used in the copper solvent extraction on copper efficiency. The study of the contact time, the PO/PA ratio and the pH showed that their increase leads to an increase in the extraction yield with a maximum efficiency of 98.4 % Cu. On the other hand, considering the disengagement time, the washing showed only a net advantage for the case of copper extraction in aqueous continuity and is little influenced in organic continuity. Washing is therefore of considerable interest in ensuring the performance of the solvent extraction circuit at Luita plant. Télécharger l'article