Experimental Investigation of Gas/Slag/Matte/Tridymite Equilibria in the Cu-Fe-O-S-Si-Al-Ca-Mg System in Controlled Gas Atmosphere: Experimental Results at 1473 K (1200 °C), 1573 K (1300 °C) and p(SO2) = 0.25 atm

The effect of temperature, CaO, MgO and AlO on important technological copper smelting parameters, such as the chemically dissolved copper in slag and the composition of the liquid phase in equilibrium with tridymite, are experimentally characterised as a function of copper concentration in matte. Two series of experiments for the gas/slag/matte/tridymite equilibria in the Cu-Fe-O-S-Si system at p(SO) = 0.25 atm have been carried out. The effect of CaO at 1573 K (1300 °C), and the combined effect of AlO + CaO + MgO at 1473 K (1200 °C) and 1573 K (1300 °C) have been measured in the first and second series of experiments respectively. The experimental methodology involves high temperature equilibration of samples on a substrate made from the primary phase under controlled gas atmosphere (CO/CO/SO/Ar), followed by rapid quenching of the equilibrium condensed phases and direct measurement of the phase compositions using the Electron Probe x-ray Microanalysis. The resulting data are used in the optimization of the thermodynamic database for the copper-containing systems.