Feasibility Study of Differential Flotation of Cu–Pb–Zn Minerals from Copper Sulfide– Oxide Ores

Abstract

t In this research, flotation of copper, lead and zinc minerals from a copper oxide–sulfide ore was studied. The identification tests showed that the sample is a mixture of quartz, chalcopyrite, galena, cerussite, hemimorphite and iron oxide minerals with 5.04% CuO, 1.61% PbO, 2.07% ZnO and 56.40% SiO2. The experimental design methodology (RSM) was conducted to investigate the effect of parameters such as pH, collector, depressant, dispersant, preparation time and size of particles on Cu– Pb–Zn minerals flotation in three steps: sulfide bulk flotation, oxide bulk flotation and sulfide differential flotation. The experiments showed that the pH, potassium amyl xanthate and sodium silicate variation influence copper, lead and zinc recoveries. In the first step, recovery of Cu– Pb sulfide reached 45.49% with grade of 15.96% for Cu and 61.65% with grade of 7.4% for Pb. In the third step, the recovery and grade of Cu enhanced to 88% and 18.3%, respectively. The optimization of parameters was conducted by software, and the supplementary tests were done by considering the optimal conditions. Under optimal conditions, the recovery of copper and lead was, respectively, 88% with grade of 24.5% in Cu concentrate and 81% with grade of 13.8% in Pb concentrate.