Solvent extraction and kinetic studies of copper from a heap leach liquor using CuPRO MEX-3302

Abstract

ABSTRACT The present study aims at assessing the potential application of CuPRO MEX-3302 in copper extraction from a heap leaching liquor. The role of influential significant parameters, including the leachate pH (0.1–2.7), CuPRO MEX-3302 concentration (5–15% (v/v)), temperature (25–70 °C), copper initial concentration (0.5 to 2.3 g/L) and extraction time (0–5 min), were investigated. The extraction efficiency at ambient temperature, 1:1 organic/aqueous phase ratio, 5% (v/v) extractant concentration, pH of about 2 and contact time of 30 min was found to be 95% with a value of Fe and Mn of less than 2%. Meanwhile, a two-step extraction process was dedicated on the basis of the McCabe-Thiele diagram to obtain an organic phase containing 2.9 g/L copper at pH of 2.1. Equilibrium analyses confirmed the association of 4 mol of CuPRO MEX-3302 per mole of extracted copper. The thermodynamic outcomes revealed a high affinity of the extractant together with an endothermic and spontaneous nature of copper extraction in the system studied. Moreover, the reaction kinetics showed that the reaction order of H+ and CuPRO MEX-3302 concentration was −0.54 and 0.50, respectively. Finally, a two-stage counter-current stripping simulation at Vo/Va = 1:1 with 180 g/L H2SO4 resulted in a copper stripping efficiency of 99.54%.