Dissolution Kinetics of Copper from Low-Grade Goldfieldite ore by Hydrometallurgical Routes

Abstract

In recent times, almost 25% of global copper obtained by leaching-cum-solvent extraction routes is considered profitable for the manufacturing of high-quality cathode material. The dissolution kinetics of copper from low-grade goldfieldite ore was examined in ammonia–ammonium sulfate media. In this study, the influences of leachant concentration, reaction temperature, and particle size on goldfieldite ore dissolution were considered. Thus, the experimental results affirmed that the dissolution rate increases steadily with increase in leachant concentration, reaction temperature, and decreasing particle sizes. At established conditions (0.5 mol/L NH₃–(NH₄)₂SO₄; 75 °C; and 45 µm), 89.9% dissolution efficiency was achieved within 120 min. The activation energy (Ea) and reaction order calculated to be 34.8 kJ/mol and 1.045 supported the diffusion control mechanism with a first-order relation. Hence, the pregnant leach solution obtained at the optimal leaching conditions was accordingly treated and beneficiated to produce a high-grade copper chloride (CuCl₂: 00-348-1947), recommended for various industrial utilities.