Fig. 6: Redox cycling of oxygen storage materials in an FBR.
Two typical samples were tested: CuMgAl-MMO-LS (low strength), and CuMgAl-MMO-HS (high strength). a Schematic diagram showing the cyclic O2 release and storage due to phase changes of CuO and Cu2O in the MMOs. b O2 volume fraction of gas during reduction and c oxidation of oxygen storage materials in the FBR. Control experiments were performed with quartz sand loaded in the reactor without the MMO. d Conversion of CuO to Cu2O over 100 redox cycles in the FBR, where partial cycling was performed by 100 cycles of partial decomposition and oxidation with periodical full decomposition of CuO every 20 cycles, and full cycling was performed by full decomposition and oxidation for 100 cycles. e TGA profiles of freshly calcined particles, particles cycled for 100 cycles in a FBR with partial decomposition (FBR PC) and oxidation with full decomposition every 20th cycle in an FBR; and particles cycled for 100 cycles with full decomposition and oxidation in an FBR (FBR FC). f XRD patterns of fresh and cycled CuMgAl-MMO-HS particles.
