Isothermal Pyrolysis of Low-Rank Coal: Kinetic Study, Batch Experiments, and Product Analysis

Document Type : Research Paper

Authors

1 Department of Chemistry, Veer Surendra Sai University of Technology, Burla, Odisha, India.

2 Department of Chemistry, School of Applied Sciences, Centurion University of Technology and Management, Paralakhemundi, Odisha, India.

Abstract

Effective use of low-grade coal is crucial for meeting global energy needs and mitigating environmental impacts, making the study of its thermal decomposition a key focus for sustainable energy development. Understanding the pyrolytic degradation process of coal is crucial for optimizing its use in eco-friendly energy solutions. It is hypothesized that the isothermal pyrolysis of low-rank coal at different temperatures will exhibit different kinetic behaviors and produce valuable condensable products. This research investigates the pyrolytic behavior, kinetics, and batch pyrolysis of low-rank coal. Thermo-gravimetric analysis was conducted under isothermal conditions at temperatures ranging from 350 to 500 °C, with a 25 °C increment, for 2 hours in an inert atmosphere. The data were analyzed using model-fitting methods, testing a total of 21 models to calculate the reaction kinetics. The results revealed that weight loss increased with temperature, reaching a maximum at 18.61% (450 °C), with activation energies of 5.817–123.51 kJ/mol. The D2 diffusion model best described the process (Ea = 7.267 kJ/mol, A = 0.022 min⁻¹). The pyrolysis index rose from 0.0113 (350 °C) to 0.051 (500 °C). At 450°C, 18.9% condensable products formed, containing alkanes, alicyclics, and aromatics (FTIR/GC-MS). These findings facilitate the optimization of sustainable pyrolysis of low-rank coal for the production of valuable outputs.

Keywords

Main Subjects

References

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Journal of Chemical and Petroleum Engineering
Volume 59, Issue 2
December 2025
Pages 271-290

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History

  • Receive Date: 26 January 2025
  • Revise Date: 18 June 2025
  • Accept Date: 30 June 2025

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