Distribution Equilibria of Pb and Cu between CaO-SiO2-Al2O3 Melts and Liquid Copper

The distribution equilibria of lead and copper between CaO-SiO2Al2O3 melts and liquid copper were measured at 1623 K under a controlled H2-CO2 atmosphere. The distribution ratios were plotted against the oxygen partial pressure, and reasonable oxide forms dissolved in the melts were estimated from the slopes of the plots. The activity coefficients of lead oxide (PbO) and cuprous oxide (CuO0.5) increased with increasing slag basicity, defined by XCaO/XSiO2. The temperature dependence of the activity coefficients of lead oxide and cuprous oxide was also measured.