(60a) Solar Thermochemical CO2 Splitting Using Ni-Based Ferrite Materials

Syngas is the feedstock for the production of liquid transportation fuels such as gasoline, diesel, and jet fuel via the Fischer Tropsch process. Solar driven thermochemical splitting of H₂O and CO₂ using metal oxide based redox reactions is considered a promising technology for the production of syngas, bypassing the utilization of fossil fuels. Ferrites are considered as one of the potential redox materials for thermochemical splitting of H₂O for the production of H₂. Among various ferrite materials, Ni-based ferrites are used comprehensively for the production of H₂ via solar-driven thermochemical water splitting cycle. Although Ni-based ferrites are very useful for H₂ production (via H₂O splitting), production of CO (via CO₂ splitting) is not much investigated. In this study, a variety of Ni-based ferrites are synthesized using sol-gel method and tested towards thermochemical CO₂ splitting reaction. After characterizing the derived Ni-based ferrite materials using PXRD, SEM, TEM, and EDS, the thermochemical CO₂ splitting ability is investigated in a thermogravimetric analyzer (TGA). All the materials are tested for more than 10 thermochemical cycles and the best Ni-based ferrite is selected based on the reaction kinetics, thermal and redox stability, and amount of CO produced per gram of the ferrite. In addition, the maximum fuel production capacity of the Ni-based ferrites is explored by conducting the thermal reduction and CO₂ splitting for an extended period. The influence of thermal reduction and CO₂ splitting reaction temperature on reaction kinetics and thermochemical fuel production ability of Ni-based ferrites is also explored. All the results obtained will be presented in detail.