Sodium trithiocarbonate as an activator for malachite xanthate flotation: Experimental study and practical application

[Display omitted] •ST is a novel activator in malachite flotation.•ST enhances flotation recovery, yielding high grades.•ST adsorbs on malachite, forming Cu-S species.•ST boosts xanthate adsorption on malachite. Effectively enriching malachite, a significant copper oxide resource, through direct flotation using the xanthate method presents challenges. This study explores sodium trithiocarbonate (ST) as a novel activator for malachite. The results of single mineral flotation experiments showed that when the pH value was 9, the dosage of ST was 2 × 10–4 mol/L, and the dosage of SBX was 1 × 10–3 mol/L, the flotation recovery rate reached the best of 92.47 %. The mineral test shows that the copper concentrate with Cu grade of 24.95 % and recovery of 91.20 % can be obtained by using ST as the yellow hydrochloric acid flotation activator of oxidized copper ore. Scanning electron microscopy and energy dispersive spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS) analysis reveal the formation of highly active copper sulfide species on malachite post-ST activation. Zeta potential and UV–visible spectrophotometer analysis indicate increased adsorption of xanthate components on malachite surfaces after ST activation. Secondary ion mass spectrometry (ToF-SIMS) supports these findings, demonstrating that copper sulfide species coverage on malachite surfaces reduces oxidation, enhancing mineral surface reactivity and promoting xanthate adsorption.