| Summary: | The performance of a perovskite-based oxygen carrier for the partial oxidation of methane in thermochemical energy storage applications has been investigated. A synthetic perovskite with formula La<sub>0.6</sub>Sr<sub>0.4</sub>FeO<sub>3</sub> has been scrutinized for Chemical Looping Reforming (CLR) of CH<sub>4</sub> under fixed-bed and fluidized-bed conditions. Temperature-programmed reduction and oxidation steps were carried out under fixed-bed conditions, together with isothermal reduction/oxidation cycles, to evaluate long-term perovskite performance. Under fluidized-bed conditions, isothermal reduction/oxidation cycles were carried out as well. Results obtained under fixed-bed and fluidized-bed conditions were compared in terms of oxygen carrier reactivity and stability. The oxygen carrier showed good reactivity and stability in the range 800–1000 °C. An overall yield of 0.6 Nm<sup>3</sup> of syngas per kg of perovskite can be reached per cycle. The decomposition of CH<sub>4</sub> catalyzed by the reduced oxide can also occur during the reduction step. However, deposited carbon is easily re-gasified through the Boudouard reaction, without affecting the reactivity of the material. Fluidized-bed tests showed higher conversion rates compared to fixed-bed conditions and allowed better control of CH<sub>4</sub> decomposition, with a H<sub>2</sub>:CO ratio of around 2 and CO selectivity of around 0.8. However, particle attrition was observed and might be responsible for a loss of the inventory of up to 9%<sub>w</sub>.
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