The distribution of cobalt between Co-Cu alloys and Al2O3-FeO-Fe2O3-SiO2 slags

The solubility of cobalt in alumina-containing iron silicate slags (0.092-3.365 wt% Co) in equilibrium with cobalt-copper-iron alloys (0.070-6.351 wt% cobalt) and oxygen pressures of 1.125.10-8, 2.396-10-9 and 4.536-10-10 atm has been studied at 1673 K. It has been found that: (I) the solubility of cobalt in the slag increased with increase in concentration of cobalt in the alloy, and also increased with increasing oxygen partial pressure in the atmosphere at a fixed concentration of cobalt in alloy; and (II) the activity coefficient of cobalt oxide in the slag increased with increasing cobalt oxide in the slag and/or decreasing oxygen partial pressure in the system. (C) Munksgaard, 2002.