(733f) Solar-Driven Thermochemical Utilization of CO2 to Produce Fuels Using Ni-Doped Iron Oxides: Experimental Evaluation and Efficiency Analysis

The Fischer-Tropsch process is an established method used to produce liquid transportation fuels, including gasoline, diesel, and jet fuel. This process involves the conversion of syngas, which is a mixture of hydrogen and carbon monoxide, into liquid hydrocarbons. Syngas is typically produced by gasification of coal, natural gas, or biomass. The excessive utilization of fossil fuels has become a major concern in recent times. Apart from depleting their finite resources, the widespread use of fossil fuels has also led to a significant increase in environmental issues. These issues include air pollution, water pollution, and the release of greenhouse gases that contribute to global warming and climate change. The negative impacts of these environmental issues can be felt on a global scale, affecting our health, ecosystems, and the overall sustainability of our planet. As such, it's crucial that we explore alternative sources of energy and adopt more sustainable practices to minimize our reliance on fossil fuels and mitigate their harmful effects on the environment. An option to create syngas is to use redox reactions based on doped iron oxide, which involves splitting H₂O and CO₂. The process consists of two steps. The first step involves the thermal reduction of iron oxides that have been doped. In the second step, the doped iron oxides are re-oxidized through the splitting of H₂O and/or CO₂, which results in the production of fuel such as H₂ or syngas. In this study, the production of Ni-doped iron oxides was achieved through a combustion synthesis method. The synthesized Ni-doped iron oxides were subjected to characterization and testing in a high-temperature thermogravimetric analyzer. The study examined the effect of operating parameters on long-term redox reactivity and fuel production capacity. Additionally, a computational thermodynamic analysis was conducted to determine the solar-to-fuel energy conversion efficiency of the Ni-doped iron oxide-driven solar thermochemical CO₂ conversion cycle.