Synthesis and characterization of bimetallic Fe/Mn oxides for chemical looping combustion

Fe-Mn mixed oxides have been prepared by different routes, characterized, and tested with TGA for application as oxygen carriers in the CLC process. These mixed oxides exhibit a lower oxygen transfer capacity than Ni based materials which is also dependant on synthesis method. In-situ XRD analysis was performed with one sample and allowed to clearly demonstrate the reaction pathway, reduction and oxidation reactions occurring stepwise, with little phase coexistence. SEM-EDS analysis on reduced and re-oxidized samples show atom migration occurs on a rather long distance, forming Fe0 and MnO particles during reduction which are oxidized back to (Fe,Mn)2O3