Abstract
This study focuses on the effects of saline water on the selective flotation of a Pb/Zn complex sulfide ore. Batch flotation experiments were carried out using NaCl solutions as well as seawater. It was found that increasing NaCl concentration in solution from 1 mM to 500 mM had a positive effect on the Pb and Zn recoveries. When comparing recoveries in the highest NaCl concentration in solution to seawater, Pb recovery decreased by 48%, most likely due to the presence of additional ions such as Ca2+ and Mg2+. On the contrary, Zn recovery in seawater increased by 55%, and this increase could be attributed to the SO42- ion effect from seawater. DLVO-like theoretical analyses using pH-dependent charge regulated models of surface charge were employed to study particle-particle and particle-bubble interactions during sulfide ore flotation under different NaCl concentrations and solution pH. The theoretical predictions of the models supported the experimental results, with a stronger particle-bubble attraction predicted by the models at higher NaCl concentrations. Overall, results demonstrated the potential of using the theoretical predictions for describing the various interactions during sulfide ore flotation in saline water.
