Accurate internal methane dry reforming kinetic models for solid oxide fuel cells

Coupling with solid oxide fuel cells, methane dry reforming is a promising pathway for energy production from two greenhouse gases. However, the influence of carbon dioxide and electrochemical reactions on the internal dry reforming reaction within the fuel cells remains debatable, requiring accurate kinetic models to describe the internal reforming behaviors. In this study, we investigated the Power-Law and Langmuir Hinshelwood–Hougen Watson models in an electrolyte-supported solid oxide fuel cell with a NiO-GDC-YSZ anode to get accurate models for internal dry methane reforming. The current density used in this study ranges from 0 to 1000 A/m2 at 973 K to 1173 K to estimate various kinetic parameters. The influence of the electrochemical reactions on the adsorption terms, the equilibrium of the reactions, the activation energy, the pre-exponential factor of the rate constant, and the adsorption equilibrium constant were studied. Furthermore, the adsorption enthalpy and entropy were investigated for the first time to understand the Gibbs free energy of CO2 adsorption. The accuracy of kinetic models for estimating kinetic parameters was also evaluated. The dual-site models show better estimations than the other models and are then utilized to predict the reaction rate in the fuel cell. The derived kinetic parameters were consistent with values reported in the literature, confirming the reliability and general applicability of the developed models. For the first time, the adsorption enthalpy, entropy, and Gibbs free energy of CO2 adsorption were quantified in a DRM–SOFC system, providing new thermodynamic insight into electrochemically influenced adsorption behavior. However, the dual-site LHHW models’ accuracy was still insufficient, indicating a need for further research to develop a comprehensive kinetic model for internal dry reforming in fuel cells. This study provides essential parameters for future simulations and highlights the need for a more detailed examination of reforming kinetic models.