スラグ中の酸化亜鉛の熱力学的考察 (第2報)

抄録

The activity coefficients of zinc oxide in molten slags of FeO-Fe₂O₃-SiO₂-ZnO and FeO-Fe₂O₃-SiO₂-ZnO-CaO were measured at about 1200°C.
A molten slag was brought into equilibrium with a gas mixture of CO, CO₂, and Zn vapor which was prepared by passing a CO-CO₂ gas mixture through a layer of pure ZnO pellets at about 1000°C. According to the desire to study the slags both saturated and not saturated with silica, crucibles of silica and platinum were used respectively. The molten slag, equilibrated with the gas mixture, was quenched in the flush of Ar gas and analysed for FeO, Fe₂O₃, SiO₂, ZnO, and CaO.
It was found that the activity coefficients of zinc oxide did not change so much as the variation of the composition of the gas mixture and that for the slags which were not saturated with silica they multiplied from 1.8 to 3.1 with the increase of the content of CaO from zero to over 16.5 weight per cent. In case of silica saturated slags, the addition of CaO varied only the saturation concentration of silica and the activity coefficients of zinc oxide were about unit.