Heterogenous carrier flotation technique for recovering finely ground chalcopyrite particles using coarse pyrite particles as a carrier

Abstract

• • Cu 2+ -treated pyrite improved fine chalcopyrite flotation recovery as a carrier. • • CuSO 4 treatment of pyrite improved its hydrophobic interactions with fine chalcopyrite particles. The recovery of fine mineral particles in flotation is limited owing to the low collision probability between the particles and air bubbles. The carrier flotation method can enhance fine particle recovery by attaching fines to coarse carrier particles. In this study, an attempt was made to improve the recovery of chalcopyrite fines using coarse pyrite particles as a carrier. Flotation experiments for finely ground chalcopyrite (D 50 ∼ 3 µm) were conducted with and without coarse pyrite (–125+106 µm) using potassium amyl xanthate as a collector. The results showed that untreated pyrite did not act as an effective carrier and that the amount of fine chalcopyrite attached to pyrite was not significant; furthermore, Cu recovery into froth was around 65% both with and without pyrite. When pyrite was pre-treated with a CuSO 4 solution, its carrier ability improved owing to a significant amount of fine chalcopyrite becoming attached to the Cu 2+ -activated pyrite particles and being recovered with pyrite into the froth (Cu recovery, >90%). Overall, the treatment of pyrite with CuSO 4 improved its hydrophobicity, which improved its hydrophobic interactions with fine chalcopyrite particles. Thus, the Cu 2+ -treatment of pyrite promotes the attachment of fine chalcopyrite particles for their increased recovery from fines.