The effect of collector's type on gold and silver flotation in a complex ore

Gold and silver are recovered by gravity concentration, cyanidation, or flotation from ores. The choice of those processes depends on the mineralogical characterization as well as gold and silver contents of the ore. Flotation has been applied on ores containing free gold and silver particles for many years. The flotation efficiency of gold and silver particles depends on the modifiers and collectors. This paper presents the results of the effect of different collector combinations on gold and silver recoveries from lead and zinc ores by flotation. Best results were obtained on the use of Aero 208+Aerophine 3418 A as collectors at the dosages of 350+350 g/t and 1000 g/t Na₂SiO₃ as a depressant at pH 4.5 where particle size was below 38μm. According to the process, a concentrate assaying 1026.9 g/t Au and 10185 g/t Ag was obtained. On the other hand, a concentrate containing 50.6% Pb was obtained with 39.7% recovery using potassium amyl xanthate (KAX) and aminothiophenol (ATP). This concentrate graded 235 g/t Au and 3740 g/t Ag.