Galvanic Couple-Induced Depression Effect with Clean and Efficient Regulation Regime of Cu-Mo Separative Flotation

It is difficult to depress secondary copper sulfide minerals in the separative flotation of copper–molybdenum coexisting ores with a huge NaHS consumption, and causing serious safety and environmental problems. Galvanic interaction between active metallic granular (low consumption depressant; LCD) and secondary copper sulfide mineral particles can induce surface passivation, thereby depressing its floatability and achieving clean and efficient regulation of copper molybdenum separation. The use of 10% LCD was applied at the first stage and 5 kg/t NaHS at the second stage can recover 89.71% of Cu, while only 52.89% of Cu can be recovered for single stage flotation where 20 kg/t NaHS was used without any presence of LCD. To avoid the negative effect of Mg(OH) 2 colloids at higher pH at the second stage, sodium hexametaphosphate (SHMP) was added as a dispersant and Mo recovery could be pulled up to 89.63%.