Powered by Blucher Proceedings

Seminários de Redução, Minério de Ferro e Aglomeração


ISSN 2594-357X

Título

EFFECT OF REDUCTANT TYPE ON THE REDUCTION OF CHROMITE FINE ORE

EFFECT OF REDUCTANT TYPE ON THE REDUCTION OF CHROMITE FINE ORE

Autoria

DOI

10.5151/2594-357x-34Red-551-560

Downloads

0 Downloads

Resumo

The present paper determines the behavior of a Brazilian chromite (Jacurici concentrate) regards to the carbothermic reduction through a thermo-gravimetric analysis in non-isothermic kinetics approach, using different types of reductant: graphite, charcoal and petroleum coke. The results have shown that the ore starts reducing at about 1350°C using graphite as a reductant and at about 1250°C using charcoal or petroleum coke. Applying the Coats and Redfern solution for non-isothermic kinetics considering the global process controlled by diffusion in the product layer, the apparent activation energies of about 290 kJ/mol, 330 kJ/mol and 460 kJ/mol were obtained, respectively for petroleum coke, charcoal and graphite. The differences might be related to the reactivity of the reductants. The value of the apparent activation energy for the experiments employing graphite was very similar the previous works using an isothermic kinetic approach. This fact confirms again the applicability of the non-isothermic approach to analyze kinetically reduction processes.

 

The present paper determines the behavior of a Brazilian chromite (Jacurici concentrate) regards to the carbothermic reduction through a thermo-gravimetric analysis in non-isothermic kinetics approach, using different types of reductant: graphite, charcoal and petroleum coke. The results have shown that the ore starts reducing at about 1350°C using graphite as a reductant and at about 1250°C using charcoal or petroleum coke. Applying the Coats and Redfern solution for non-isothermic kinetics considering the global process controlled by diffusion in the product layer, the apparent activation energies of about 290 kJ/mol, 330 kJ/mol and 460 kJ/mol were obtained, respectively for petroleum coke, charcoal and graphite. The differences might be related to the reactivity of the reductants. The value of the apparent activation energy for the experiments employing graphite was very similar the previous works using an isothermic kinetic approach. This fact confirms again the applicability of the non-isothermic approach to analyze kinetically reduction processes.

Palavras-chave

chromite, carbothermic reduction, non-isothermal kinetics, reductant, thermogravimetric analysis

chromite, carbothermic reduction, non-isothermal kinetics, reductant, thermogravimetric analysis

Como citar

Neto, Flavio Beneduce; Takano, Cyro; Moura, Marcelo Breda. EFFECT OF REDUCTANT TYPE ON THE REDUCTION OF CHROMITE FINE ORE, p. 551-560. In: 34º Seminário de Redução de Minério de Ferro e Matérias-Primas, None, 2004.
ISSN: 2594-357X, DOI 10.5151/2594-357x-34Red-551-560