PERFORMANCE OF COLLECTORS AND FROTHERS IN DIRECT SULPHIDE AURIFEROUS FLOTATION

The gold mineralization in the study area (Princesa Isabel - PB) is a gold-quartz-sulfide vein type (lode gold), but in this mine and others close to the region, the miners are submitting the curimas (waste) through rudimentary process. The primary gold is disseminated in the rocks, where are also (secondarily) veins of quartz, most often mineralized. The gold found in the mini-fractures of the deposits probably is associated with intensive shear processes by hydrothermal alteration sulphide that occurred in the area. This work presents some results of the gold sulphide flotation. The best results of gold concentration were obtained with a composition of ethyl xanthate (C2XK), at a concentration of 30 g/t and sodium dithiocarbamate (C4H6N2S4Na2) 20 g/t, at pH congruent to 10. It was used to direct flotation, in which minerals of interest floated and separated in the foams are accompanied by waste minerals, as demonstrated by the experimental results. Flotation tests with the synergistic effect of the collectors C2XK and Na(CH3)(2)NCS2 were obtained a 169 ppm grade (38 times enrichment).