Effect of mechanical activation on the soda roasting kinetics of chromite

Year 2010, Volume: 14 Issue: 2, 128 - 133, 01.12.2010

Kenan Yıldız Güven Yarkadaş

Abstract

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Keywords

chromite, chromate, soda roasting kinetics, mechanical activation

Kromitin soda kavurması kinetiğine mekanik aktivasyonun etkisi

Abstract

Soda roasting kinetics of non-activated and mechanically activated chromite was investigated. It was determined that the reaction was diffusion controlled between 700 900°C and chemical reaction controlled between 900 1200°C. The activation energy of first step for soda roasting of non-activated chromite was 170 kJ/mol and this value decreased to 141.8 kJ/mol for 30 min activated chromite and 79 kJ/mol for 120 min activated chromite. The activation energies for the second step was calculated as 64.7 kJ/mol for non-activated chromite, 43 kJ/mol for 30 min activated chromite and 25.1 kJ/mol for 120 min activated chromite. Mechanical activation reduced the activation energy for the soda roasting of chromite.

Keywords

kromit, kromat, soda kavurması kinetiği, mekanik aktivasyon

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