Session: 06-02 Materials and Fundamentals

Paper Number: 115295

115295 - Parametric Study of Solar Chemical-Looping Reforming of Methane Using Ni Promoted Ceria 

Solar chemical looping reforming of methane (CLRM) to produce syngas, a mixture of CO and H₂, is a promising route to storing solar energy as a chemical commodity. Syngas is used as feedstock for various gas-to-liquid technologies to produce liquid fuels, which are compatible with the existing transportation sector. Fuel produced using syngas from solar CLRM has an upgraded calorific value compared to syngas produced via non-solar methods, and, as a relatively stable chemical commodity, can be stored on longer time scales than other forms of solar thermal storage. CLRM utilizes an oxygen exchange intermediate to split the methane reforming reaction into two steps: 1) the partial oxidation of methane (POM) to produce CO and H₂ via reduction of the metal oxide, followed by 2) re-oxidation of the metal oxide coupled with CO₂ and/or H₂O splitting to produce additional CO and/or H₂. Ni catalyzed CeO₂ (Ni-CeO₂) has been identified as a promising oxygen exchange material to promote high rates of syngas production at low operating temperature. In this work, we investigate CLRM with Ni-CeO₂ in a packed bed reactor system using unmodified CeO₂ as a baseline. Notably, methane conversion and syngas selectivity with Ni-CeO₂ at low temperatures of 700-800 ℃ are comparable to CLRM with commercial CeO₂ at higher operating temperatures of 1000-1100 ℃. A parametric study of reactor conditions, including temperature, gas velocity, and inlet methane concentration, is also conducted to investigate the effect of each of these factors on methane conversion, syngas selectivity, and overall syngas production in packed-bed reactor. Insight from this work will motivate choice of operating conditions for future work towards optimization of CLRM with Ni-CeO₂. 

Presenting Author: Caroline Hill University of Florida

Presenting Author Biography: Caroline graduated from the University of Tennessee in 2017 with a B.S. degree in Mechanical Engineering. Post-graduation, she worked with the Mechanical R&D department at Siemens Healthcare to design the next generation of Positron Emission Tomography/Computed Tomography (PET-CT) technology. Currently, she is working as a graduate research assistant at the University of Florida Renewable Energy Conversion Laboratory studying redox materials and methods of operation to improve solar thermochemical processes.