With the rise in global demand for pure copper, there is an urgent need to consider the processing of low-grade chalcopyrite ores. Ammoniacal leaching solutions have been reported as effective and efficient leachants for the dissolution of chalcopyrite. This work reports on different parameters that influence the leaching kinetics of a Nigerian chalcopyrite-rich siderite ore obtained from the Wase local government area (9°5’43’’N9°57’29’’E) of Plateau state, Nigeria, and assayed as 11.30 weight percent copper. At the optimum leaching conditions of 0.4 mol/L ammonia-ammonium sulfate (NH3-(NH4)2SO4) leachant concentration, 75 °C reaction temperature and 45 µm particle size, the extent of chalcopyrite ore dissolution reached 87.4 percent within 120 minutes. The dissolution rate was affirmed to conform to the diffusion control mechanism, and an activation energy of 38.84 kJ/mol and a reaction order of 0.661 for the leachant concentration were established.
Mining, Metallurgy & Exploration (2023) 40:161–169, https://doi.org/10.1007/s42461-022-00728-4