Partial oxidation of CH4 with air to produce pure hydrogen and syngas

The gas–solid reaction between methane and the lattice oxygen of Ni, Co, and Fe-oxides loaded on various support materials produced a synthesis gas (hydrogen and carbon monoxide) at 600–800 °C. Metal oxides were reduced to metals or lower valence oxides, and they were re-oxidized to oxides by introducing air after the reaction. Thus, production of hydrogen or synthesis gas free from nitrogen can be achieved alternatively without using pure oxygen. As a metal oxide, Fe₂O₃ and Rh₂O₃-loaded on Y₂O₃ exhibited the highest H₂ selectivity of 60.1% with a moderate CH₄ conversion of 54% and a high lattice oxygen utilization of 84% at 800 °C.