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  • 1 School of Chemical Sciences, Kannur University, Payyanur Campus, Edat. P.O, Kannur 670327, Kerala, India
  • | 2 Department of Chemistry, Christ College, Irinjalakuda, Kerala, 680 125, India
  • | 3 R & D Division, Sud—Chemie India Pvt Ltd., Binanipuram, Kerala, 683 502, India
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Abstract

The kinetics of the reduction of nickel, cobalt and copper ferrites was studied by the temperature programmed reduction method at different heating rates in hydrogen atmosphere. The activation energy values of the reduction processes were calculated using the non-isothermal isoconversional method according to the Kissinger-Akahira-Sunose equation and the dependence of apparent activation energy on the degree of conversion was determined. The carbon monoxide oxidation activities of all the three samples were determined at various temperatures up to 140 °C. An interesting correlation between the apparent activation energies for the reduction process was observed. The decreasing trend of activation energy on the ‘extent of conversion’ in all cases showed that the reduction is a multi-step process involving a reversible process followed by an irreversible step.