Preparation of copper-based oxygen carrier supported by titanium dioxide

Chemical-looping combustion (CLC) is an indirect oxygen combustion strategy, considered to be the most cost-effective power generation technology with the carbon dioxide (CO2) inherently concentrated. The oxygen carriers in the combustion process are subjected to severe environments, such as high temperatures, multi-cycle operations, and thermodynamic limitations. Thus, the preparation of an oxygen carrier with high durability and better kinetics under harsh environments could be an essential part of the development of the CLC process. In this study, copper oxide (CuO) was selected as an active ingredient, and was supported on the titanium-dioxide-based supporting materials, which was either directly from commercial titanium dioxide powder (TiO2) (anatase 99 %) or from tetrabutyl titanate, depending on methods. Three preparation methods were applied, including mechanic mixing (MM), sol–gel (SG), and wet impregnation (WI). Test results indicated all prepared oxygen carriers functioned properly in the multi-cycles of reduction and oxidation (redox) in thermogravimetric under 800 °C. Characterization and activity tests revealed that the CuO, prepared by the SG method was well-dispersed, highly active, and thermally stable in redox reactivity than those by the MM and WI methods. Furthermore, nucleation and diffusion models could better describe kinetics of prepared oxygen carrier based on the SG method.