Leaching kinetics of near infrared sensor-based pre-concentrated copper ores by sulphuric acid
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Camborne School of Mines, University of Exeter
Department of Chemistry, Nasarawa State University
Department of Industrial Chemistry, University of Ilorin
College of Agriculture
Department of Chemistry, University of Ilorin
Amos Idzi Ambo   

Nasarawa State University, Department of Chemistry, Faculty of Natural and Applied, Sciences, Nasarawa State University, Keffi, 1022 Keffi, Nigeria
Publication date: 2016-12-01
Physicochem. Probl. Miner. Process. 2017;53(1):489–501
Leaching kinetics of near infrared sensor-based preconcentrated copper ore was investigated to understand its leaching behaviour in a sulphuric acid solution. The leaching process was studied by monitoring the effect of some parameters under optimum conditions. The process kinetics was determined by fitting the experimental data into the shrinking core model. Contrasting results were obtained for the preconcentrated ore. The results indicated that increasing the acid concentration and temperature as well as decreasing the particle size and stirring speed enhanced the leaching rate of copper above 80%. The leaching efficiencies of 95.5 and 83.7% were obtained after 2 h leaching under the studied experimental conditions. Good correlation coefficients were obtained with the experimental data when the data were fitted into the chemical reaction controlled model. The activation energy was calculated to be 39.8 and 50.03 kJ/mol for the preconcentrated ore indicating that dissolution of copper occurred through the chemical reaction on the particle surface. Characterization of the residue by a X-ray diffraction (XRD) technique revealed abundant peaks of quartz and other associated minerals which were unreactive toward the lixiviant. A inductively coupled plasma spectroscopy (ICP-MS) analysis showed reduction in metal concentration in comparison to the raw ore which evidently conformed to the ore reactivity in the acid media.