Effects of coarse chalcopyrite on flotation behavior of fine chalcopyrite

Abstract

The flotation of ultrafine particles is marked with low recovery due to low collision efficiency between particles and bubbles. Carrier-flotation is a method to enhance the recovery by the attachment of fine particles onto larger carrier particles. In this study, the effects of coarse chalcopyrite particles as a carrier on flotation behavior of fine chalcopyrite was investigated by the flotation experiments using 20 g fine chalcopyrite (particle size D50 = 2.3 µm) with a varied amount of carrier particles of different sizes (–75 + 38 µm and –106 + 75 µm) using a 400 mL-mechanically agitated flotation cell. The addition of carrier particles improved the recovery of ultrafine particles into the froth from around 25% (without carrier) to around 80% (with 20 g of carrier, –75 + 38 µm size). Recovery of fine particles was higher with smaller carrier size (–75 + 38 µm) compared with larger carrier size (–106 + 75 µm), though the difference was not significant. Theoretical calculations showed that hydrophobic interaction played a more dominant role compared with van der Waals force in the attachment of fine chalcopyrite particles on the carrier (larger chalcopyrite particles).