Solid-state reduction of chromite with carbon was studied as a function of temperature,C/FeO ratio and chromite particle size.Experiments were carried out using TGA and the reaction products were analyzed using SEM-EDAX and X-ray diffraction.The results showed that the significant reduction of chromite takes place between 500 and 700 deg C .A plot of weight loss vs temperature showed slopes of the same magnitude for the temperatures from 250 to 500 deg C and 700 to 1100 deg C.The reaction products formed are long cylindrical tubes that are high in chromium.An expression for a two dimensional diffusion (infinite cylinder shape particles) controlled reaction was proposed.The activation energy,effective diffusivity and k_p values were deduced.The control of diffusion through the product layer is the rate controlling step.A reduction reaction mechanism was proposed.
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