Effect of NaO on the Reduction of FeO Compacts with CO/CO.

Compacts of FeO and FeO doped with varying amounts of NaO were isothermally reduced at several temperatures, using CO/CO mixed gas in a vertical resistance furnace. To determine the effect of NaO on the reduction of FeO compacts, the mass loss due to oxygen removal was continuously recorded, from which the reduction rate and rate constant were obtained. NaO was found to retard the reduction of FeO compacts. The apparent activation energy ( E) of reaction and the mathematical relationship for pore gas diffusion suggested that the reduction behavior at the initial stages was controlled by a combination of pore gas diffusion and interfacial chemical reaction. At the intermediate and late stages of reduction, pore gas diffusion was the sole contributing factor. Morphological examination of the reduced compacts showed the formation of a liquid phase during the reduction process, which appeared to lower the rate of reaction. [ABSTRACT FROM AUTHOR]