Investigations on the utilization of konjac glucomannan in the flotation separation of chalcopyrite from pyrite

Abstract To selectively separate chalcopyrite from pyrite, the effect of konjac glucomannan on the flotation separation of chalcopyrite from pyrite was investigated in this study. The results of single mineral flotation tests showed that konjac glucomannan had a stronger depression effect on pyrite than traditional organic depressants (Starch, Dextrin, Guar gum) with the pyrite recovery less than 5% at the pH range of 5–11, while it had little influence on chalcopyrite flotation over the whole pH range. Flotation tests of mixed minerals were conducted to further study the selective depression effect of konjac glucomannan, and a copper concentrate with CuFeS2 grade of 83.69% and Cu recovery of 85.64% could be obtained from a feed containing 47.20% CuFeS2. This was due to the greater adsorption of konjac glucomannan on the surface of pyrite than that on chalcopyrite surface, which was also proved by the results of zeta potential measurements, adsorption measurements, and FTIR studies. Furthermore, XPS test results manifest that konjac glucomannan adsorbed on pyrite was via physical adsorption. Hydrogen bonding and Bronsted acid-base interaction were considered as the main driving forces.