ABSTRACT
Oxidation of sulfides is one of the most important and most complex pyrometallurgical processes, usually called roasting. In this unit process the sulfide ore or concentrate is heated in a suitable reactor usually with air or oxygen to achieve one of the following goals: partial oxidation, oxidation to sulfates and complete removal of sulfur. For a better understanding of the oxidation of sulfides it is essential of know their thermal stability. When heated in an inert atmosphere, sulfides may volatilize or dissociate. The oxidation of sulfides is a highly exothermic process and the heat generated in many cases is ample to sustain the reaction without extra fuel. Oxidation of sulfides by SO2 offers an important advantage, namely the possibility of recovering the sulfur content in the feed material as elemental sulfur. Sulfide ores are usually a complex mixture. The behavior of such a mixture in oxidation is not necessarily the sum of the oxidation of each sulfide taken separately.
