Syngas production through H2O/CO2 thermochemical splitting

Thermochemical H2O/CO2 splitting is considered one of the most appropriate solution technologies for the sustainable and environmentally friendly production of H2 and CO. The two steps process is the most promising technology: in the former the solar-driven endothermic reduction of metal oxides occurs, that in latter exothermic step are re-oxidated by water or carbon dioxide giving syngas and re-generating the catalyst. The "ideal" metal oxide should be able to optimise both steps allowing to occur at the lowest temperature the oxidation and the reduction. The ceria-zirconia systems (CeO2-ZrO2) seem to outperform the materials developed to date, even if the working temperatures are still too high. In this work, CeO2-ZrO2 based materials containing suitable dopants were prepared using hydrothermal and co-precipitation techniques in order to lower the oxidation/reduction temperatures. The developed materials were characterised (BET; XRD...) and their activity was tested by TG analysis and in a lab-scale reactor. The results show that a ceria zirconia sample prepared by hydrothermal method shows the best redox properties. Furthermore, the doping allows to lower the working temperatures