Perovskite structure oxygen carriers with the general formula CaMnxMg1-xO3-?? were spray-dried and examined in a batch fluidized\r\nbed reactor. The CLOU behavior, reactivity towards methane, and syngas were investigated at temperature 900�°C to 1050�°C. All\r\nparticles showed CLOU behavior at these temperatures. For experiments with methane, a bed mass corresponding to 57 kg/MW\r\nwas used in the reactor, and the average CH4 to CO2 conversion was above 97% for most materials. Full syngas conversion was\r\nachieved for all materials utilizing a bedmass corresponding to 178 kg/MW. SEM/EDX and XRD confirmed the presence of MgO in\r\nthe fresh and used samples, indicating that theMg cation is not incorporated into the perovskite structure and the active compound\r\nis likely pure CaMnO3-??.The very high reactivity with fuel gases, comparable to that of baseline oxygen carriers ofNiO, makes these\r\nperovskite particles highly interesting for commercial CLC application. Contrary to NiO, oxygen carriers based on CaMnO3-?? have\r\nno thermodynamic limitations for methane oxidation to CO2 and H2O, not to mention that the materials are environmentally\r\nfriendly and can utilize much cheaper raw materials for production. The physical properties, crystalline phases, and morphology\r\ninformation were also determined in this work.
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