Akademik Veri Yönetim Sistemi
Journal of the Faculty of Engineering and Architecture of Gazi University, cilt.39, sa.3, ss.1541-1553, 2024 (SCI-Expanded)
In this study, the recovery of Zn from Balıkesir-Balya Pb-Zn ores by acid leaching method was investigated. H2SO4, HCl and HNO3 were used as solvent reagents in leaching processes. According to the results obtained, optimum conditions were defined for each acid and the most suitable acid for the leaching method was determined considering its dissolution efficiency (Table A). In addition, temperature-dependent kinetic analyzes were performed for all three acids in this study. In this context, in order to determine the kinetic model controlling the total reaction rate, the situations under the chemical controlled model, diffusion controlled model, and film diffusion model were examined separately and appropriate kinetic models were determined for each acid. Purpose: The aim of this study is to investigate the recovery of zinc from lead-zinc ores in Balikesir province, Balya district, by leaching method, and to determine the appropriate solvent and optimum parameters. Theory and Methods: The effects of several parameters such as the particle size, solid ratio, leaching time, acid dosage and pulp temperature on dissolution efficiencies of Zn were investigated under different conditions of 75-106-150 µm particle size, 5-10-15-20-25% solid ratio, 30-60-120-180-240 min leaching time, 0.25-0.5-1-2-5 M acid dosage, and 30-40-50-60-70°C leaching temperature. In order to determine the kinetic model controlling the overall reaction rate within the scope of dissolution kinetic analysis, the situations under the chemical controlled model, diffusion controlled model and film diffusion model were examined separately and appropriate kinetic models were determined for each acid. By applying the relevant kinetic models to the results obtained from H2SO4, HCl and HNO3 experiments, the variation of the dissolution rate depending on the temperature was tried to be revealed. For each acid, experiments were carried out under the conditions of -106+75 µm particle size, 1 M acid dosage, 20% solids ratio, 0-30 min leaching time, 50-90 oC pulp temperature and 250 rpm mixing speed. Results: Optimum results were obtained under the conditions of 75 µm (H2SO4 and HNO3) and 106 µm (HCl) particle size, 15% (H2SO4), 25% (HCl) and 20% (HNO3) solids ratio, 120 min (H2SO4) and 60 min (HCl and HNO3) leaching time, 0.5 M (H2SO4 and HCl) and 1M (HNO3) acid dosage and 50℃ (H2SO4 and HNO3) and 70 oC (HCl) pulp temperature. As a result of the experiments carried out under these optimum conditions, 97.32%, 96.38% and 96.06% Zn dissolution efficiencies were obtained, respectively. When the leaching kinetics for the H2SO4, HCl and HNO3 experiments were examined, the dissolution efficiencies obtained at different temperatures were plotted and the apparent rate constants and correlation coefficients were calculated from the slope of the lines obtained. When these values were examined, it was seen that the dissolution of Zn complied with the diffusion-controlled model in the Shrinking Core Model in all three acid medias. Activation energies were calculated from the slope of the Arrhenius plot line as 3.615 kJ/mol for H2SO4, 4.811 kJ/mol for HCl and 4.736 kJ/mol for HNO3. Conclusion: Chemical enrichment studies carried out in this study showed that more scientific research can be done on the recovery of zinc contents with known ore processing methods in Balıkesir Balya lead-zinc ore samples, and new methods can be tried.