TELLURIUM DISTRIBUTION IN COPPER ANODE SLIMES SMELTING

Tellurium is a common minor constituent of copper anode slimes. The di stribution of tellurium between the phases during slimes smelting is a n important consideration, both in terms of metal quality and the capt ure of the oxidized tellurium. In this work, the oxidation by oxygen a t 1100 degrees C of a silver-copper selenide matte containing 2 pet te llurium has been examined. The distribution of tellurium between the p hases was determined as the extent of oxidation increased, and the sys tem was modeled using a computational thermodynamics package. Oxidized tellurium was found to report to the slag, with none being removed wi th the gas. The thermodynamic model predicted, to an acceptable level, the tellurium content of all phases as oxidation progressed. It was u sed to show that oxidation by air rather than oxygen results in higher residual tellurium levels in silver metal and that the lower the smel ting temperature, the greater the extent of tellurium elimination from silver to the slag.