In the research of a continuous ironmaking process from a reduced iron, or a pre-reduced iron ore, the reducing rate of iron oxide in molten slag by carbon in iron melt was investigated to know the optimum reducing condition. Mixture consisted of, mainly, 40 g master slag and 17.1 g iron oxide was added onto the iron melt in a graphite crucible, the copper melt in a graphite crucible, or the iron melt in an alumina crudible to measure the amount of CO gas evolved at 13201620°C. The following results were obtained;
(1) The reducing rate of iron oxide in molten slag was proportional to the second power of iron oxide content in molten slag except for the starting and the ending period of experiment.
(2) The rate constant and the apparent activation energy of the reduction of iron oxide in molten slag by carbon in iron melt were obtained from data of experiment with a graphite crucible-iron melt and a graphite crucible-copper melt.
(3) The rate constant of reduction of iron oxide in molten slag by the carbon in iron melt, or a solid graphite was greatest at CaO/SiO2=1.5 of molten slag.
