Reaction kinetics of reduction and oxidation of metal oxides for hydrogen production

• Published in: International journal of hydrogen energy Vol. 33; no. 21; pp. 5986 - 5995
• Main Authors: Go, Kang Seok, Son, Sung Real, Kim, Sang Done
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.11.2008; Elsevier
• Subjects: Alternative fuels. Production and utilization; Applied sciences; Diffusion controlling reaction; Energy; Exact sciences and technology; Fuels; Hydrogen; Hydrogen production; Mn- and Zn-cation iron oxides; Redox kinetics of metal oxide; Thermogravimetric analysis; Water splitting; Water splitting; Thermogravimetric analysis; Redox kinetics of metal oxide; Mn- and Zn-cation iron oxides; Diffusion controlling reaction; Hydrogen production; Methane; Iron oxide; Partial oxidation; Solid state; Manganese oxides; Chemical decomposition; Kinetics; Activation energy
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2008.05.039

Partial oxidation of methane and water splitting for hydrogen production were carried out. The reaction kinetics of reduction and oxidation (redox) of Mn and Zn iron oxides were determined using a thermogravimetric analyzer. The reduction conversion of the metal oxides increases with temperature above 1073 K and all the experimental data are well represented by the diffusion-limited mechanism except ZnFe 2O 4 due to the solid state diffusion of iron and the reaction with solid carbon. The oxidation reaction was also controlled by the product-layer diffusion mechanism. Substitution of Mn and Zn cations with iron oxides can lower the reaction temperature and increase the reaction rate. The reaction rate and the activation energy (57–110 kJ/mol) for decomposition of water by oxidation of the metal oxides were also determined.