Abstract
Lowering the reduction temperature of iron oxide is of great significance in applied engineering, but challenging to achieve in a hydrogen tube furnace as the partial pressure of hydrogen is limited to 1 atm. In this study CaH2 was used as a drying agent to control the partial pressure of water vapor to lower the reduction potential of iron oxide. By comparing the extent of formation of the reduction product α-Fe in Fe3O4 reduced under hydrogen with and without CaH2 at various temperatures, the presence of CaH2 was shown to lower the temperature required for complete reduction from 400 °C to 300 °C accompanied by an increase in the H2/H2O ratio of the outlet gas. Thermodynamic calculations indicated that the addition of CaH2 increases the reduction potential, causing a higher production ratio of α-Fe. These findings indicate that CaH2 promotes reduction by efficiently absorbing the water vapor generated during reduction.
Original language | English |
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Article number | 122441 |
Journal | Journal of Solid State Chemistry |
Volume | 302 |
DOIs | |
Publication status | Published - 2021 Oct |
Keywords
- CaH
- Hydrogen reduction
- Iron oxide
- Metal hydride
- Thermodynamics
- Water potential
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry