Thermochemical Hydrogen Production Using Ni-Ferrite and CH₄

Hydrogen production by a 2-step water-splitting thermochemical cycle using metal oxides (ferrites) redox pairs and CH₄ have been studied in this experiment. Reactions were performed in a two-step redox cycle in which the ferrites were reacted with CH₄ at 700°C–800°C to produce CO, H₂, and various reduced phases (reduction step); these were then reoxidized with water vapor to generate H₂ in water-splitting step (oxidation step) at 600°C–700°C. The reduced forms of Ni-Fe2O3, Ni-FeO and Ni-Fe alloy from XRD, showed respectively different reactivity for H₂ formation from H₂O. These were oxidized to the ferrite phase to produce H₂ in the water-splitting step at 600°C–700°C. In reduction reaction at 800°C, carbon deposition arise on surface of Ni-ferrite due to CH₄ decomposition. This reduced phase containing carbon, which reacts with H₂O at 600°C, produce H₂, CO, and CO₂. The amount of H₂ evolved using reduced phase containing carbon was much than that of other phase.