Chemical looping combustion (CLC) is a novel CO2, capture technology with inherent separation of N-2 with CO2, produced by fossil fuel combustion. Fe-based oxygen carrier is one of the most promising oxygen carriers for solid-fuel CLC with respect to its low cost. However, most Fe-based oxygen carriers have very low reactivity and would result in a large portion of unbumt gases at the outlet of the fuel reactor. The fuel combustion is less efficient with unbumt components in the product, and the CO2, concentration is not high enough for the subsequent capture and storage. To eliminate the unburnt gas and improve the CO2, purity, a two-stage CLC process is proposed by combining the normal CLC with the low-temperature CLC, and a cement-supported Cu-based oxygen carrier was developed for the low-temperature CLC procedure. Thermogravimetric analysis (TGA) results indicated that the Cu/cement oxygen carrier had relatively fast oxidation and reduction rates at low temperatures (similar to 300 degrees C). Experimental results obtained from the single fluidized bed showed that unburnt CO can be converted fully with this oxygen carrier at low temperatures with no agglomeration. The developed oxygen carrier was also tested for more than 18 h in a dual fluidized-bed reactor and demonstrated that CO can be converted fully in the fuel reactor, and the oxygen carrier particles did not show any tendency to form agglomeration.