Mechanism and kinetics of pyrite transformation at elevated temperatures

Alvaro Aracena, Oscar Jerez

Resultado de la investigación: Contribución a una revistaArtículorevisión exhaustiva


Pyrite (FeS2) is known as a sulfide that provides energy for various pyrometallurgical processes (fusion and conversion). There are several studies related to the evaluation of pyrite oxidation mechanisms at high temperatures, obtaining discrepancies in the products generated. In our work, the novelty of our research would be to obtain the thermochemical oxidation mechanism of FeS2 by using conventional thermogravimetric methods. The oxidative roasting of pyrite from 550 to 800°C was analyzed for an oxygen concentration of 5.07 to 28.06 kPa of oxygen and particle size between 12.3 to 33.8 microns. The results showed that the pyrite proceeded by sequential roasting: first, it produced an intermediate compound, pyrrhotite (Fe7S8), which was later oxidized to generate hematite (Fe2O3), both stages validated by weight loss of the sample as well as by analysis by DRX. Each stage had a different roasting speed as it was also influenced differently by different parameters. The temperature and particle size favored the rate of pyrrhotite generation, and the oxygen concentration favored the rate of hematite formation. The first-order kinetic equation ln (1-XPy) represented the roasting of the first stage (FeS2 → Fe7S8), with a calculated activation energy of 70.1 kJ/mol. The order of reaction was 0.5 concerning the partial pressure of oxygen and inversely proportional to the initial particle radius.

Idioma originalInglés
Páginas (desde-hasta)127-139
Número de páginas13
PublicaciónPhysicochemical Problems of Mineral Processing
EstadoPublicada - 2021
Publicado de forma externa


Profundice en los temas de investigación de 'Mechanism and kinetics of pyrite transformation at elevated temperatures'. En conjunto forman una huella única.

Citar esto