Depression mechanism of Na2CS3 on pyrite in lime- CuSO4 system

The unavoidable presence of ionic substances in the ore pulp can adversely effects on the separation of pyrite from other valuable metal sulfide ores. Developing new reagents to eliminate this effect is of great significance. In this study, a novel approach was proposed to depress pyrite by utilizing sodium trithiocarbonate (Na 2 CS 3 ) as a depressant in the lime-CuSO 4 system. The results of the micro-flotation experiments showed that a low dosage of Na 2 CS 3 in the lime-CuSO 4 system could effectively depress pyrite. The presence of CuSO 4 in the solution which improves the ability of BX to adsorb on the surface of the pyrite was also revealed by the analysis of LEIS, UV–Vis, and contact angle, while the addition of Na 2 CS 3 effectively hindered the adsorption of BX. XPS and SEM-EDS analysis results showed that Na 2 CS 3 forms a complex with Cu 2+ and adsorbs onto the pyrite surface, thereby impeding the adsorption of the collector and effectively depressing pyrite.