Treatment of sulphide ores - involves heating iron pyrite in controlled atmos. to separate sulphides by volatilisation

摘要

This invention relates to method and apparatus for treating a sulfur containing material having at least one principal sulfide either in the form of a sulfide or in a form that is transformable into a sulfide and at least one auxiliary sulfide more volatile than the principal sulfide or transformable into another sulfide more volatile than the principal sulfide, wherein the sulfurous material is heated in one furnace zone, having a non-oxidizing atmosphere in the gas phase, to a temperature between that required for volatilization of the principal sulfide and that required for volatilization of the auxiliary sulfide to volatilize the auxiliary sulfide and labile sulfur, without volatilizing or substantially oxidizing the principal sulfide; and heating the sulfurous material in another furnace zone, having an oxidizing atmosphere in the gas phase, to a temperature lower than that required for substantial oxidization of the principal sulfide, to oxidize the volatilized labile sulfur and auxiliary sulfide, without substantially oxidixing the principal sulfide.