Flotation of Spodumene Against Quartz by Punicines

Five pH- and light-switchable punicine derivatives were investigated as collectors in the flotation of spodumene and quartz. At the natural pH of the minerals, the punicine substituted with a C17 alkyl residue showed the best recovery under daylight (>5000 lux), with values up to 65.0% and 97.8%, and also the highest absolute recovery difference between the two minerals. For pH values of 2 and 12, the punicine collector with a viologen moiety and a C9 alkyl residue shows the best absolute recovery difference, with values of 32.45% and 32.88%, respectively. Studies on the influence of pH, particle size distribution, UV light and darkness, ζ-potential measurements, and IR spectroscopic measurements were carried out to gain insight into the mechanisms.