Sulfidation mechanism of cerussite in the presence of sulphur at high temperatures

In this paper, sulfidation mechanism of cerussite in the presence of sulphur at high temperatures was investigated based on micro-flotation, X-ray powder diffractometry (XRD), electron probe microanalysis (EPMA) and X-ray photoelectron spectroscopy (XPS). The micro-flotation test results showed that flotation recovery of the treated cerussite increased to above 80% under a suitable flotation condition. It was found that the S/PbCO3 mole ratio and pH obviously affected flotation recovery. XRD analysis results confirmed that the cerussite was decomposed into massicot and then was transformed into mainly PbS and PbO center dot PbSO4 after sulfidation roasting. EPMA analysis results demonstrated that surface of the obtained massicot was smooth, but surface of the artificial galena was rough and even porous. Content of oxygen decreased, whereas content of sulphur increased with an increase in the S/PbCO3 mole ratio. XPS analysis results revealed that various lead-bearing species, including mainly PbS, PbSO4 and PbO center dot PbSO4, were generated at the surface. Formation of PbS was advantageous to flotation of the treated cerussite. Based on these results, a reaction model of the cerussite sulfurized with sulphur was proposed.