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Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics
Published on: April 12, 2019
Multiscale Perspectives on Char Oxidation: Reaction Regimes, Transport Phenomena, and Modeling Challenges.
Jiuling Yang1,2, Xiang Wu1, Lei Yang1
1School of Engineering, Sichuan Normal University, Chengdu 610101, China.
ACS Omega
|June 15, 2026
Summary
This review examines char oxidation reactivity, highlighting how transport limitations and pore structure significantly influence reaction kinetics. Understanding these factors is crucial for accurate modeling of combustion processes.
Area of Science:
- Chemical Engineering
- Combustion Science
- Materials Science
Background:
- Char oxidation reactivity is critical for energy conversion and fire safety.
- Existing research often overlooks the interplay between intrinsic kinetics, transport phenomena, and pore structure.
Purpose of the Study:
- To critically assess current research on char oxidation reactivity.
- To elucidate the influence of transport limitations and pore structure on char reactivity.
- To bridge the gap between intrinsic kinetics, apparent kinetics, and macroscopic combustion behavior.
Main Methods:
- Comparative analysis of intrinsic and apparent reaction kinetics.
- Systematic review of methodologies for pore structural parameter determination.
- Critical review of bed-scale char oxidation under various regimes.
Main Results:
- A linear correlation (log A_in = 0.069 E_in - 1.55) was found for intrinsic char oxidation due to compensation effects.
- Apparent kinetic parameters show significant variability, underscoring diffusion limitations.
- Ambiguity exists in selecting pore structural parameters due to a lack of unified formulations.
Conclusions:
- Diffusion limitations significantly impact char reactivity, affecting apparent kinetic parameters.
- Multiscale modeling incorporating dynamic pore structure evolution is needed to bridge kinetic and macroscopic behaviors.
- This review provides a foundation for modeling char oxidation in energy conversion and combustion systems.
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