A Simulation Framework for Implementing a Detailed Kinetic Model for Dry Reforming of Methane

Dry Reforming of Methane (DRM) is a promising route for syngas production while valorizing and eliminating important greenhouse gases such as CO₂ and CH₄. However, its high endothermicity demands efficient heat transfer at temperatures above 1073 K, and catalyst deactivation by coking remains a major challenge. In particular, we are analysing the use of liquid metal reaction media to avoid coking accumulation. Developing reliable process models for such reactor concepts requires the integration of detailed reaction kinetics with robust process simulation tools. This work presents a methodological framework for implementing complex, multi-step Langmuir–Hinshelwood (L-H) kinetic models. The framework is demonstrated through a case study on DRM coupled with the Reverse Water-Gas Shift (RWGS) reaction, tailored for a hypothetical liquid metal catalytic environment. A detailed 23-step surface mechanism is simplified by assuming the dissociation of adsorbed CH₄ and the surface reaction between adsorbed CO₂ and H as the Rate-Determining Steps (RDSs) for DRM and RWGS, respectively. It incorporates the unique properties of liquid metals, such as weak adsorption and carbon dissolution into the bulk, to minimize coke formation terms. The derived rate equations are implemented in custom Python scripts to model an isothermal Plug-Flow Reactor (PFR), using literature-derived kinetic parameters as a baseline. However, the calculation runs into the lack of experimental data that allow its validation, which becomes a critical aspect to be able to estimate the chemical kinetics of the reaction itself. As a result, a series of experiments are proposed to validate these design tools for DRM in liquid metal. The results highlight the framework's capability for preliminary performance assessment and sensitivity analysis. This study provides a foundational kinetic framework open-access workflow for incorporating advanced heterogeneous kinetics into process simulation, serving as a template for evaluating novel reactor designs where commercial simulator options are limited or cost-prohibitive.

The core contribution of this work is procedural and computational. It provides a clear, reproducible pathway from fundamental kinetic theory to executable process simulation. Key achievements of the framework include

- The seamless integration of user-defined kinetic expressions within steady-state reactor models.
- The ability to model coupled reaction networks (DRM and RWGS) with proper thermodynamic consistency.
- The facilitation of sensitivity analyses, crucial for identifying critical parameters (e.g., adsorption constants) for future experimental campaigns.

Future work should focus on applying this framework to systems with available experimental data for full validation and the adjusted kinetic parameters for specific liquid metal alloys. Furthermore, model extension to adiabatic and multi-stage reactor configurations, coupled with techno-economic analysis, is essential to advance the industrial feasibility of this promising technology for sustainable syngas production. Critical technical milestones include the construction of fluid-mechanic demonstrators, the execution of high-temperature reaction experiments, and the development of specialized structural materials and carbon extraction systems capable of sustained high-temperature operation.