Experimental and thermodynamic modelling investigation of the phase equilibria in the CaO-“FeO”-AlO 1.5 system in equilibrium with Fe metal has been undertaken to characterise the thermochemistry of slag in pyrometallurgical processes. Phase equilibria data at 1100-1615°C were obtained using equilibration of synthetic mixtures with predetermined compositions in Fe foil/wire or Al 2 O 3 crucibles, quenching, and electron probe X-ray microanalysis of the phases. Phase equilibria and liquidus isotherms in the lime (CaO), wustite (FeO x ), spinel (FeAl 2 O 4 ), corundum (Al 2 O 3 ), calcium aluminates (CaAl 2 O 4 = CA, CaAl 4 O 7 = CA 2 , CaAl 12 O 19 = CA 6 , Ca 3 Al 2 O 6 = C 3 A, Ca 12 Al 14 O 33 = mayenite), dicalcium ferrite (Ca 2 (Fe,Al) 2 O 5 = C 2 F, brownmillerite), and calcium iron aluminate (Ca 3 FeAl 4 O 10 = C 3 FA 2 , found for the first time) primary phase fields were revealed. The experimental results were used to develop a thermodynamic database for describing the CaO-“FeO”-AlO 1.5 system. Also, the composition of solid phases versus slag composition was analysed through the experimental results and thermodynamic database developed in this study.
Abdeyazdan et al. (Wed,) studied this question.