Behavior of Copper and Sulfur During High-Temperature Sulfurization Of Copper-Smelting Slags with Elemental Sulfur

The article presents the results of experimental sulfidization of smelt and converter slags of copper smelting production using granular elemental sulfur at a temperature of 1300 °C in an inert atmosphere without hydrocarbon or metal reducing agents. The distribution of sulfur over products and the behavior of copper are considered. It is shown that feeding elemental sulfur to the slag recovers magnetite and sulfidizes iron, forming a sulfide phase whose yield increases with the consumption of elemental sulfur. An increase in the sulfur consumption leads to a decrease in the concentration of copper in the matte and slag. In the range of sulfur consumption considered, the copper content decreases to less than ~ 0.1% in smelt slag and to ~ 0.2% in converter slag. The concentration of sulfur in the gas is high. The maximum uptake of sulfur by the melt does not exceed ~ 49%. The results obtained indicate the possibility of using elemental sulfur without additional reducing agents to sulfidize copper-smelting slags, either rich or poor in copper, to a high degree of copper recovery.