Study on sulphidization roasting and flotation of cervantite

•Sulfidation roasting and flotation behavior of cervantite were studied for the first time.•Provide a technical solution for antimony oxide separation.•Morphological characteristics of cervantite after sulfidation roasting were studied. A new technology, sulphidization roasting of antimony mineral cervantite with elemental sulfur followed by froth flotation is reported in this paper. The effects of roasting temperature and time, sulfur to antimony molar ratio on the properties of treated product and its flotation behavior were studied. Optimum roasting conditions are: roasting temperature 723K; roasting time 30min; and sulfur to antimony molar ratio of 1.5. Under these conditions, the mineral phase changed from cervantite to stibnite as expected. The flotation recovery of the sulphidized cervantite is over 90%. A flotation concentrate grading 21.04% Sb with a recovery of 77.15% is achieved by sulphidization roasting and flotation from a feed grading 1.11% Sb in which cervantite is the main antimony mineral.