Chemical looping combustion of low-volatile semi-anthracite coal with Co-based metal oxide: Performances, kinetics, and mechanisms
Publication Date
Spring 1-2025
Description
The kinetics of Chemical Looping Combustion (CLC) using Co3O4 as an oxygen carrier for low-volatile semi-anthracite coal were studied with the aim of integrating CO2 capture into the combustion process. The effectiveness of varying temperature regimes (800–950 °C) and oxygen carrier ratios (ϕ = 0.5–2.0) on the CLC process was evaluated. The findings indicate a distinct two-stage combustion sequence: initially, the combustion of volatiles with solid Co3O4 occurs between 460 and 650 °C, followed by the combustion of fixed carbon with gas-phase oxygen released from Co3O4 between 750 and 950 °C. Moreover, the activation energy for volatile combustion was found to be 82 kJ/mol, while for fixed carbon combustion during the non-isothermal stage, it ranged from 31 to 140 kJ/mol. During the isothermal stage, the activation energy for fixed carbon combustion was approximately 234 kJ/mol, with a reaction rate constant (k₀) of 3.7 × 108 s⁻1. The kinetics varied from diffusion-controlled reactions at lower temperatures to first-order or phase-boundary-controlled reactions, and then to Avrami-Erofeev modeled kinetics at higher temperatures, influenced by both temperature and oxygen carrier ratios. This pioneering study provides a comprehensive analysis of the multi-stage kinetics of solid fuel CLC, bridging gaps in current knowledge and laying the groundwork for improved design and efficiency of CLC systems for cleaner energy conversion.
Journal
Journal of the Energy Institute
Volume
119
Department
Chemical Engineering
Link to Published Version
https://www.sciencedirect.com/science/article/pii/S1743967125000212
DOI
https://doi.org/10.1016/j.joei.2025.101993
Recommended Citation
Okolie, Jude and Güleç, Fatih. "Chemical looping combustion of low-volatile semi-anthracite coal with Co-based metal oxide: Performances, kinetics, and mechanisms." (2025) .
