Industrial development of a novel sulfate system for copper pyro-refining

The results of a complete series of industrial-scale tests carried out at the Noranda Horne smelter using a novel molten sulfate salt for copper pyro-refining are described in this article. In the process, copper co-exists with a molten oxide layer and a molten CaSO₄-Na₂SO₄ layer, both of which have refining capabilities. The effect of the composition of the sulfate salt and that of the copper oxide slag on the distribution of minor elements between copper, oxidic slag, and the sulfate phase are presented. Pascal Coursol is a Ph.D. candidate at the Center for Computational Thermochemistry (école Polytechnique de Montréal) and is currently a process scientist with Alcan International. Nathan Stubina is a Six Sigma master black belt and Eva Carissimi is smelter manager with Noranda Inc.-Horne Division. Manuel Zamalloa and Phillip Mackey are principal scientists with Falconbridge, respectively, at Falcondo Division and the Falconbridge Technology Center.