FLOATABILITY OF CHALCOPYRITE IN THE PRESENCE OF DIALKYL-THIONOCARBAMATE AND SODIUM-SULFITE

The use of sodium sulfite in the flotation of sulfide ores using a dialkyl-thionocarbamate as collector enables us to obtain, in most cases, a good selectivity for copper sulfide from other sulfides. However, under certain conditions, we observe some possibilities of chalcopyrite depression. The results related here attempt to delineate the parameters leading to a deterioration in the selectivity of the chalcopyrite flotation. The roles of mill type, pH regulator, more or less pronounced superficial oxidation, pollution by iron from the mill, etc. are considered. The conjunction of grinding without iron oxide pollution (by using a stainless steel mill), the presence of galena-pyrite mixture, Ca2+ ions, and oxidizing conditions, has the effect of strongly depressing the chalcopyrite.