ARSENOPYRITE ENRICHMENT BY COLUMN FLOTATION

Arsenic-rich, gold-bearing pyrite concentrates may be further enriched in arsenic to assist subsequent Au beneficiation. Among several amine s tested in refloating a local Chalkidiki pyrite concentrate, 2-coco 2 -methyl ammonium chloride proved successful by raising the grade from 9% to 22%, although total solids recovery was low. The use of a froth- stabilizing frother was also beneficial to the process. Optimum hydrod ynamic conditions were : intermediate pulp flowrate, low wash water an d gas flowrate; the latter abated the mixing/dispersion process in the collection zone.