Investigations on the selective flotation of chalcopyrite from talc using gum Arabic as depressant.

The flotation separation of chalcopyrite from talc is difficult due to their good natural floatability. To solve this problem, the effect of gum Arabic (GA) on the flotation separation of chalcopyrite from talc was systematically investigated and its selective depression mechanism was discussed. Single mineral flotation test results showed the addition of GA could effectively depress the flotation of talc across the whole pH tested, while had a negligible effect on chalcopyrite in the pH range of 6–8. The mixed minerals flotation tests demonstrated that the effective separation of chalcopyrite from talc could be achieved with a concentrate of 31.36% Cu grade at 87.15% Cu recovery in the presence of GA. This was attributed to the greater adsorption density of GA on talc surface than that on chalcopyrite surface. In addition, compared to the concentrate (Cu grade: 27.01%, Cu recovery: 87.03%) with guar gum as the depressant, an increase of 4.35% of Gu grade was obtained with the use of GA. The results of X-ray photoelectron spectroscopy (XPS) measurements and zeta potential tests indicated that GA adsorbed on talc surface mainly via hydrophobic interaction and hydrogen bond may also play a role. [ABSTRACT FROM AUTHOR]