Analysis by chemical potential diagram of the oxidation of molten silver selenide

An understanding of the thermodynamics of copper-anode slimes smelting is a prerequisite for process improvements to this old technology. During slime s smelting a silver-copper selenide matte is formed and subsequently oxidiz ed to silver metal-a process similar to copper matte converting. As part of a series of investigations into copper-anode slimes smelting, molten silve r selenide matte was oxidized at 1100 degrees C with pure oxygen. The chemi cal potential diagram for the system was developed and used for qualitative prediction of the results of the experiments. A simple, computational ther modynamic model of converting is presented, the adjustable parameters of wh ich were determined by matching the model with the experimental results. Th e practical usefulness of the model was demonstrated by predicting the effe ct of smelting temperature and use of either oxygen or air as the oxidizing gas on the recovery of silver.