Reactivity of DME-fueled Chemical-looping Combustion Using (CoO+1.0% PtO2)/CoAl2O4 for Solar heat Storage

The thermochemical process is considered as a promising way of solar energy storage. Here, we propose an innovative storage method integrating thermochemical process with chemical looping combustion, providing a promising solution to the problem of large energy penalty for CO2 capture, and achieving the solar thermal energy storage with solid material. For this specific purpose, a new thermal energy storage composite material has been developed, which is the subject of the present paper. A oxygen carrier of (CoO+1.0% PtO2)/CoAl2O4 is synthesized for this new technology and experiments are implemented to investigate its reactivity, the carbon deposition behavior and the redox stability. The results indicate that the new looping material shows a good reactivity at reduction temperature of 673 K. To avoid carbon deposition, DME is saturated with the mole ratio of H2O/DME varying from 0 to 2.0, and the appropriate H2O/DME ratio is 1.0. The redox stability of the oxygen carrier is tested by the cyclically utilization in 30 cycles, and compared to CoO/CoAl2O4, the redox stability is relatively improved. The results obtained in this paper may provide the possibility for the solar thermochemical storage method combining with the chemical-looping combustion.