Abstract
The present study is concerned with the kinetics of carbon reduction of MnO and the identification of Mn carbide formed in this reduction process by the effluent gas analysis method. The results are as follows:
(1) At the earlier stage of reduction, Mn carbide (Mn7C3) was formed, and the activation energy of 217 kJ/mol which is nearly equal to that for the Boudouard’s reaction was obtained.
(2) When carbon was consumed entirely, the reaction between MnO and Mn7C3 to yield metallic manganese occurred, and the activation energy of 259 kJ/mol which corresponds to the reaction of CO2 with Mn7C3 was obtained.
(3) Mn carbide formed in the reduction process of MnO was identified to be Mn7C3 phase, by the effluent gas analysis method using the He-O2 mixture. In addition, EPMA and X-ray diffraction examinations showed the presence of Mn7C3 phase in this reduction product.
