LOOPING SULFIDE OXIDATION™ PROCESS FOR ANODE COPPER PRODUCTION Dr. Leonid N. Shekhter 1 , Dr. Corby G. Anderson 2 , Daniel G. Gribbin 1 , Esra Cankaya-Yalcin 1 , Joseph D. Lessard 1 , Larry F. McHugh 1 1 Orchard Material Technology, 231 Sutton Street, Suite 1A, North Andover, MA 01845 2 Kroll Institute for Extractive Metallurgy, Colorado School of Mines, Golden, CO 80401 Keywords: Copper Smelting, Anode Copper, Flash Smelting, Looping Sulfide Oxidation™ Abstract A new process for smelting copper, Looping Sulfide Oxidation™ (LSO™) significantly and positively alters the smelting energy balance. This process uses copper oxide in conjunction with air for the desulfurization of copper and chalcopyrite concentrates. Copper oxide is regenerated in a flash type furnace and then “looped” back for the oxidation of the copper concentrate. Heat and material balances show that the Looping Sulfide Oxidation™ process requires significantly lower net energy than conventional technology. This process produces anode copper and higher SO2 content off-gases for efficient formation of sulfuric acid. Additionally, the process yields slags with lower copper solubility as compared to the conventional technology. Introduction Based on the positive results from LSO™ investigations [1], further lab investigations into common sulfides and metal oxides were performed. It was discovered that chalcopyrite (CuFeS2) is oxidized with copper (II) oxide. In this reaction over 98.5% of sulfur was removed as SO2, while a significantly improved energy balance was observed. This paper intends to analyze both the conventional flash smelting process and the newly developed Looping Sulfide Oxidation™ process, comparing heat and material balance results. LSO™ yields improvements to the energy footprint for copper, opening the door to new copper processing opportunities. Current Copper Smelting Practice De Re Metallica [2] details the mining, smelting, and refining techniques and technologies of the 16 th century. Little has changed in the chemistry of copper production since then. Of the numerous copper smelting processes [3, and references therein, 4], one of the more frequently employed practices is the flash smelting and converting setup to produce anode-quality copper. While this typical copper smelting methodology is highly effective, there is an ongoing effort to improve the environmental and energy “footprint” of the process. This has been previously studied and documented by Pitt and Wadsworth [5].The production of partially oxygen-enriched air is energy intensive. The SO2 streams are at low concentrations due to the excess air introduced during smelting and converting, which requires significantly increased equipment size and leads to less efficient energy capture and higher capital cost. Finally, the slag