Kinetics of the reaction between Pb-Sb complex sulphide concentrates and water vapour by

Pb-Sb complex sulphide concentrates (major phase is jamesonite (FePb4Sb6S14) and PbS, ZnS, SiO2 and FeS are minor phases), mainly distributed in the Guangxi Zhuang antonomous region, are important resources of lead and antimony in China. Presently they are treated by pyrometallurgical process1–5, as shown in Figure 1. Although it has some advantages, its major disadvantages are inferior Pb-Sb separation, low direct recoveries of Pb (68%) and Sb (40%), and meaningless recycling of Pb and Sb in the smelting process. The existing pyrometallurgical flowsheet usually produces low-quality antimony or even leadantimony alloy. The Pb-Sb separation is a key problem in treating this kind of Pb-Sb complex sulphide concentrates. Moreover, the problem with this process is that the sulphur dioxide generated during fluid bed roasting can not be efficiently recovered due to its low concentration. In the present investigation, the leadantimony separation technology for the Pb-Sb complex sulphide concentrates by oxidative volatilization roasting with water vapour is proved to be highly effective6. The direct recoveries of Pb and Sb are >94% and >93%, respectively. The emission of sulphur-bearing gases during the volatilization roasting process of the Pb-Sb complex sulphide concentrates will be considerably reduced. However, the kinetics and mechanism of oxidation of the Pb-Sb complex sulphide concentrates with water vapour have not been studied. It is worthwhile to study the kinetics and mechanism of oxidation of the Pb-Sb complex sulphide concentrates with water vapour.