A-site cation deficient La1-xFeO3-δ oxygen carriers for chemical looping dry reforming of methane in a fluidized bed reactor

Chemical looping dry reforming of methane (CL-DRM) in fluidized bed reactors represents a promising approach for the conversion of CO 2 and CH 4 into hydrogen-rich syngas. However, the development of oxygen carriers (OCs) with both high reactivity and sufficient mechanical stability under fluidized bed conditions remains a critical challenge. In this work, A-site cation-deficient La 1-x FeO 3- δ OCs were synthesized and evaluated for CL-DRM applications in a fluidized bed reactor. The effects of A-site cation-deficient level (x in La 1-x FeO 3 - δ ), particle size, and fluidization velocity on CH 4 conversion were investigated. Among the tested materials, La 0.95 FeO 3- δ exhibited the highest catalytic activity, achieving a CH 4 conversion of 75 %, a CO selectivity of 97.5 %, and a syngas yield (H 2 + CO) of 9 mmol/g, while maintaining stable performance over 10 redox cycles at 850 °C. Fine particles (100–200 μm) show higher CH 4 conversion compared to larger particle sizes (200–300 μm), mainly due to improved gas–solid contact associated with the combined effects of minimum fluidization voidage ( ε mf ) and apparent gas residence time ( τ) . X-ray diffraction and scanning electron microscopy confirmed that the La 1-x FeO 3- δ OCs maintained good mechanical integrity and chemical stability under fluidized bed operating conditions. The addition of a binder significantly improved mechanical strength and reduced the attrition rate by approximately 50 %. These findings demonstrate the potential of A-site cation-deficient La 1-x FeO 3- δ as robust OCs for CL-DRM in fluidized bed reactors.