Partial oxidation reforming of methane to synthesis gas by chemical-looping using CeO₂-modified Fe₂O₃ as oxygen carrier

The CeO₂/Fe₂O₃ oxygen carriers were prepared by co-precipitation method and their characterization was carried out using X-ray diffraction (XRD) and scanning electron microscope (SEM). The partial oxidation reforming of methane was tested in a fixed-bed at different operating conditions. The temperature programming results show that 30% CeO₂-modified Fe₂O₃ has rather better effect than pure Fe₂O₃; the conversion of CH₄, the selectivity of H₂ and CO are greatly improved. Same results have been observed in isothermal experiments. As the reaction time is less than 1 200 s, there is no carbon deposit formed. After 15 cycles, 30% CeO₂-modified Fe₂O₃ has the best cycling performance at 850 ℃ and the reaction time of 945 s. The conversion of CH₄ reaches to 91.53%, the selectivity of H₂ and CO reach to 86.36% and 85.12%, respectively and the H₂/CO mol ratio in syngas is 2.03. The species of substance in oxygen carriers has no obvious change after 15 cycles.