Effect of low dissolved oxygen on chalcopyrite-molybdenite separation flotation at high altitude areas

Abstract

Given the scarcity of conventional low-altitude high-quality copper–molybdenum resources, people gradually explore mining opportunities in elevated regions. Molybdenite in high-altitude ores is initially recovered with chalcopyrite, which is then separated and floated to produce refined molybdenite. There are few studies on the influence of the sulfide ore flotation process under high-altitude and low dissolved low-dissolved oxygen (DO) environments. In the present study, a flotation plant is designed and assembled to simulate the flotation of chalcopyrite at high altitudes by controlling the partial pressures of N2/O2 and DO under different altitude conditions, using the DO value as a standard. UV/VIS, electrochemical, and contact angle measurements were used to reveal the effect of conditions at 4600 m DO = 4.0 mg/L at altitude on chalcopyrite–molybdenite separation. Pure mineral flotation results indicate that a low DO environment at high altitudes favors the separation process and reduces the number of inhibitors. The mechanism of chalcopyrite inhibition at high altitudes still relies on the adsorption of large amounts of Fe(Ⅲ)-O/OH and hydrophilic polysulfides on the surface. Results reveal the reason for the relatively low inhibitor dosage in the chalcopyrite–molybdenite separation flotation process under low DO conditions at high altitudes. The findings also confirm that enhanced collector removal at high altitude altitudes is conducive to implementing a pathway toward a more efficient separation flotation process.