| In order to evaluate the reaction kinetics of zinc ferrites reduced by hydrogen, the studies were made on the thermal decomposition of synthetic zinc ferrites in vacuum and on the process of hydrogen reduction at various temperatures and pressures by thermal balance method, so that the parameters of the equation of reducing processes were determined. The results were discussed with the comparison of the rate of zinc and iron oxides. Zinc ferrites were easily decomposed into gaseous zinc and solid magnetite in vacuum at elevated temperatures, then by introduction of hydrogen to the vacuum, the decomposition was followed with the reduction of magnetite into the ferrous oxide, and finally the reaction completed by the formation of metallic iron. The rate of reduction of zinc ferrite at the initial stage may be expressed as follows: 1-(1-Y)^(1/3)=K_0P^(0.92)_(H2) t/ρ·r_0 The activation energies were calculated as 22 ㎉/㏖ for the thermal decomposition, and 17.2 to 17.4 ㎉/㏖ for the hydrogen reduction, respectively. |
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