Sulfur Species in Particulates Emitted from Reducing Coal Combustion and Pyrometallurgical Furnaces

The method of X-Ray Photo-electron Spectroscopy is used to determine the chemical state of the sulfur species present in fly-ash samples produced by burning a number of pulverized coal samples under reducing conditions in a continuous combustion furnace. The influence of submicron metallic constituents present in the flue-gases of the pyrometallurical systems on the state of the sulfur species emitted from the burning chamber and produced on the surface of ZnO particulates is thiosulfate. This material, which is relatively stable at the normal workroom conditions, is not as toxic as previously seen metallic sulfur compounds produced under oxidizing conditions.