Optimisation of fine auriferous pyrite recovery using anionic and non-ionic collectors

Abstract

The beneficial effects of the synergy between two or more anionic reagents have long been known. The purpose is to increase both the recovery and selectivity. In this study, the flotation of fine auriferous pyrite particles (<38 μm) was studied using a mixture of anionic and non-ionic collectors. When Z-105 was used for non-ionic collector and mixed with anionic reagents, the flotation results showed a better recovery of auriferous pyrite than that was obtained compared with using collectors alone. The adsorption of anionic/non-ionic collectors mixture and single anionic collectors was investigated. The adsorption density of collectors on auriferous pyrite surface was increased slightly when an anionic/non-ionic collector mixture was used compared with anionic collector alone. IR spectra results showed that no new absorption peaks appeared after the adsorption of Z-105 on auriferous pyrite. Z-105 adsorption occurred in molecular form. When anionic mixture was used for collector together with non-ionic collector (Z-105), a concentrate assaying 12.12 g t⁻¹ Au was produced at Au recovery of 90.8%. Compared with using anionic collector mixture alone, the Au recovery was significantly improved. The use of anionic and non-ionic collector mixtures shows great potential for industrial application.