Combined effect of operating variables on performance and kinetic of lead flotation.

This study aims to investigate the effects of pH and chemical reagents to model and optimize the flotation process of a complex lead ore containing 2.44 wt% Pb. For this purpose, the effects of pulp pH, collectors (PAX and R404), depressant (FeSo4), and activator (Na2S) concentrations were studied using response surface methodology. Furthermore, the influence of these parameters was studied on flotation kinetics parameters. The optimization studies indicated that the desired Pb recovery (84.1%) and grade (26.6%) was obtained from the test, which was performed with the optimum flotation conditions: 75 g/t PAX, 80 g/t FeSo4, 735 g/t Na2S, 20 g/t R404 and pH 9.5. The results of statistical analyses showed that the pulp pH, PAX concentration, and interactions between pH-R404 concentration and PAX concentration-R404 concentration were the most influential parameters on concentrate grade and recovery. From the kinetic studies, it was observed that the flotation rate coefficient and ultimate recovery were strongly dependent on the pulp pH. The flotation rate coefficient increased with enhancing the pH from 8 to 9.5 and after that reduced with increasing the pH to 11. [ABSTRACT FROM AUTHOR]