Modular modeling of electrochemical reactors: Comparison of CO2-electolyzers

Abstract For economic electrochemical production at industrial scale, high current densities are desired. Conversely, economic electricity utilization requires minimal overpotentials. Ultimately, product yield and composition most likely depend on both overpotential and current density. Modeling and simulation enable the detailed examination. Therefore, we develop modular mechanistic dynamic models for parts of the electrochemical membrane reactors that can be assembled to represent cell setups in order to assess their performance and optimization potential. The models include relevant overpotentials such as ohmic losses and mass transport limitations. The modelling methodology is applied to experimental CO2 reduction data in different cell setups. The novelty of the work lies in the parameter estimation to experimental data given for very different electrode/membrane configurations as well as very different gas and liquid flow configurations. The validated models allow the analysis and detailed comparison of dominant loss terms of the reactor setups indicating optimization possibilities and potentials.