Thermodynamic Study on MnO Behavior in MgO-saturated Slag Containing FeO.

Abstract

In order to understand the behavior of manganese oxide in smelting reduction process, the manganese equilibrium between ironmaking slag containing FeOand silver melt was investigated over the temperature range of 1 400-1 500'C. The oxygen partial pressure was controlled by COICO, ratio. Test results on Mn content in silver have been thermodynamically converted into those in supercooled or carbon-saturated iron melts and the activity coefficient of MnO in slag was determined experimentally. The activity of MnO decreased with increasing FeOcontent in slag. Higher FeOcontent as well as lower slag basicity resulted in larger equilibrium manganese distribution ratio between slag and iron. The temperature dependence of equilibrium manganese distribution was determined in the temperature range of 1 400-1 500'C. The relative partial molar heats of solution of MnO and Mnwere also experimentally determined.