Reverse flotation of carbonate from sulfide minerals

2004

Yongqiang Liu,

Removal of carbonate gangue and pre-concentration of sulfide minerals is necessary prior to acid pressure leaching when a refractory gold-bearing sulfide ore contains a significant amount of carbonate minerals. This is usually achieved by direct flotation of the gold and sulfide minerals into a bulk flotation concentrate. However, if the flotation recoveries of gold and sulfide are unsatisfactory, reverse flotation of the carbonate minerals is a possible alternative. In this study, calcite and dolomite were used as representative carbonate minerals, and pyrite and chalcopyrite as representative sulfide minerals to investigate the feasibility of the reverse flotation process. It was found that by using sodium oleate collector and a mixed organic depressant, selective reverse flotation of carbonate is possible.

Keywords: Flotation, sulfide ores, flotation depressants, Gold ores