Researchers have extensively studied the use of metal-oxide oxygen carriers for the delivery of oxygen via reduction of the oxygen carrier during the application of chemical looping combustion. These combustion systems, which produce a concentrated stream of CO2, potentially have significant advantages over, for example, combustion with air that requires expensive CO2 separation technologies prior to CO2 sequestration. Despite certain advantages, success has been limited due to insufficient durability and reactivity of the metal-oxide oxygen carriers, To address the above issues, copper (Cu)-based oxygen carriers have been extensively studied for the combustion of both gaseous and solid fuels.
Although Cu-based carriers demonstrate a high reactivity for fuel combustion in chemical looping combustion systems, their relatively low melting point has generated severe agglomeration problems at higher temperatures. As a result, researchers have also evaluated Fe2O3 as an oxygen carrier. Although this carrier has improved temperature stability versus CuO, its reactivity is significantly limited.
This technology addresses the above issues by providing for an oxygen carrier that demonstrates improved durability and reactivity versus metal oxides currently used in the chemical looping combustion of fuels. The carrier is composed of a combination of metal oxides offering increased reactivity per unit weight and enhanced physical durability and reactivity during multiple cycling combustion-regeneration reactions. The carrier is an optimum combination of CuO and Fe2O3 on an inert support that is reactive with fuels and provides excellent efficiency and combustion rates at relatively low temperatures.
