Kinetics of hematite chlorination with Cl(2) and Cl(2) + O(2): Part I. Chlorination with Cl(2)

Abstract

Preliminary tests of the chlorination of two iron oxides (wustite and hematite) in Various chlorinating gas mixtures were performed by thermogravimetric analysis (TGA) under non-isothermal conditions. Wustite started to react with chlorine from about 200 degrees C generating ferric chloride and hematite as the final reaction products. The presence of a reducing and oxidizing agent in the chlorinating gas mixtures influenced the chlorination reactions of both iron oxides, during non-isothermal treatment, only at temperatures higher than 500 degrees C. The chlorination kinetics of hematite with Cl(2) have been Studied in details between 600 and 1025 degrees C under isothermal chlorination. The values of the apparent activation energy (E(a)) were about 180 and 75 kJ/mol in the temperature ranges of 600-875 and 875-1025 degrees C, respectively. The apparent reaction order with respect to Cl(2) was found to be 0.67 at 750 degrees C. Mathematical model fitting of the kinetics data was carried out to determine the most probable reaction mechanisms.