Flotation of Aladagˇ oxide lead-zinc ores

Oxide lead-zinc ore sample containing 10.17% Pb, 10.98% Zn, 57 g/t Ag and 164 g/t Cd was subjected to this experimental study and taken from Kayseri located in the foothills of the Aladağ Mountains, Turkey. Preliminary flotation tests with the ore sample indicated that there was no selectivity in terms of zinc recovery; therefore studies were concentrated on producing lead concentrates. In the experiments, the effects of different parameters such as number of stages, amount of Na2S, amount of ZnSO4 and application of gravity concentration prior to flotation were investigated in relation to the metal contents of concentrates and flotation efficiencies. A lead concentrate with 65.42% Pb was produced with 77% recovery as a result of six stage flotation experiment carried out with 350 g/t KAX, 250 g/t Aero 407 and 4500 g/t Na2S and 98.7% of zinc remained in the tailings with 12.23% Zn content. As a result of gravity concentration followed by flotation, a lead concentrate with an average Pb content of 65.80% was produced with 86.5% total Pb recovery. In both cases almost all zinc remained in the tailings and could not be recovered by the addition of different reagents due to its complicated mineralogical structure. Therefore, application of metallurgical processes is proposed for zinc recovery from the tailings.