Reduction Kinetics of Compact Hematite with Hydrogen from 600 to 1050 °C

Reduction of iron ores with hydrogen is a solution to replace fossil fuels. For this reason, it important discuss previous discrepancies. Some studies suggest rate minimum respect temperature. Our research work indicates that can be avoided. Thermogravimetric isothermal reduction experiments were carried out from 600 1050 °C pure reagent ferric oxide and using tubular furnace. The morphology chemical composition the initial sample, consisting particulate hematite (Fe2O3), final product, metallic (Fe°), was defined scanning electron microscopy (SEM) X-ray diffraction (XRD). for conversion magnetite (Fe2O3 Fe3O4) highest, around 5 %/min, decreasing 2–5%/min second stage wüstite (Fe3O4 FeO). This remains almost constant about 20–80% reduction, 0.3–1%/min completion (FeO Fe°). controlling mechanism evaluated based on calculated apparent activation energy fitting experimental data one gas-solid reaction equation. Under conditions in work, linearly increased temperatures 1000 °C, without temperature range. Above decreased due sintering phenomena. result suggests maximum as reducing gas. mechanisms identified gas diffusion control iron. Since affects overall changes porosity also evaluated. Finally, schematically described.