Solubility of chlorine in aluminosilicate slag systems

Abstract

Thermodynamic properties of chlorine in the CaO-SiO2-Al2O3, Na2O-SiO2-Al2O3 and CaO-SiO2-Al2O3-Na2O slags have been investigated in the present study. The experiments were carried out using gas-slag equilibrium, controlling both PO(2) and PCl(2) simultaneously (PO(2) = 10-16-10-19 atm, PCl(2) = 10-10-10-13 atm at 1 673-1 748 K), and the solubility of chlorine in the 40mass%CaO-40mass%SiO2-20mass%Al2O3 slag was found to vary in proportion to PO(2)-1/4 and PCl(2)1/2. Accordingly, the chloride capacity (CCl(-)), which represents the ability of slags to absorb chlorine, has been defined as: CCl(-) = (mass%Cl-)PO(2)1/4/PCl(2)1/2. The CCl(-) values were observed to increase with increasing slag basicity and temperature, and showed a reasonable relationship with that of CS(2-).