Experimental phase equilibria studies in the “CuO0.5”-CaO-SiO2 ternary system in equilibrium with metallic copper

Abstract

Phase equilibria studies were undertaken on the “CuO0.5”-CaO-SiO2 system in equilibrium with metallic copper to provide fundamental information on the reactions taking place between slags and refractory materials in metallurgical furnaces. The liquidus isotherms between 1160 and 1706 °C in the tridymite and cristobalite (SiO2), cuprite (Cu2O), pseudowollastonite (CaSiO3), rankinite (Ca3Si2O7) and dicalcium silicate (Ca2SiO4) primary phase fields, and the 2-liquid miscibility gaps in the silica-rich corner and low-silica area of the system, were experimentally determined using the equilibration and quenching technique, followed by the electron probe X-ray microanalysis (EPMA) of phase compositions. The liquidus surface of the “CuO0.5”-CaO-SiO2 system has been constructed. The dissolution of copper oxide in the tridymite and cristobalite (SiO2) was shown to be negligible. The data obtained are used for the optimization of the thermodynamic database for the copper-containing systems.