Experimental Study of the Slag/Matte/Metal (Fe or Cu)/Tridymite Equilibria in the Cu-Fe-O-S-Si-(Ca) System at 1473 K (1200 °C): Effect of Ca

Abstract

A combined experimental and thermodynamic study has been carried out to determine the CaO effect on the equilibria between slag/matte/metal (Fe or Cu)/tridymite phases in the Cu-Fe-O-S-Si-Ca system at 1473 K (1200 °C). The experimental methodology included equilibration of the mixtures at high temperatures on substrates made from the primary phase, followed by rapid quenching of the samples and direct measurement of the condensed phase compositions using the Electron Probe X-ray Microanalysis (EPMA) technique. New experimental results have been obtained for fixed concentrations of CaO in slag phase (1.5, 6, 9, and 18 wt pct). All results have been plotted as functions of the copper concentration in the matte phase and provides information about the effect of CaO on the oxygen and sulfur concentration in the matte phase; the Fe/SiO2 ratio in slag; and dissolved copper and sulfur in slag. The experimental research is part of integrated experimental and thermodynamic study aimed to development and optimisation a thermodynamic database for copper-containing systems of non-ferrous metallurgy.