Effect of Na^sub 2^O on the Reduction of Fe^sub 2^O3 Compacts with CO/CO2

• Published in: Metallurgical and materials transactions. B, Process metallurgy and materials processing science Vol. 43; no. 6; p. 1326
• Main Authors: Pan, Wen, Ma, Ze Jun, Zhao, Zhi Xing, Kim, Wan Ho, Min, Dong Joon
• Format: Journal Article
• Language: English
• Published: New York Springer Nature B.V 01.12.2012
• Subjects: Chemical reactions; Iron; Metallurgy; Metals
• ISSN: 1073-5615; 1543-1916
• DOI: 10.1007/s11663-012-9738-z

Compacts of Fe^sub 2^O3 and Fe^sub 2^O3 doped with varying amounts of Na^sub 2^O were isothermally reduced at several temperatures, using CO/CO2 mixed gas in a vertical resistance furnace. To determine the effect of Na^sub 2^O on the reduction of Fe^sub 2^O3 compacts, the mass loss due to oxygen removal was continuously recorded, from which the reduction rate and rate constant were obtained. Na^sub 2^O was found to retard the reduction of Fe^sub 2^O3 compacts. The apparent activation energy (E ^sub a^) 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.[PUBLICATION ABSTRACT]