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Updated: Mar 5, 2026
07:30
Fast Pyrolysis of Biomass Residues in a Twin-screw Mixing Reactor
Published on: September 9, 2016
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A comprehensive kinetics study of coconut shell waste pyrolysis
Imtiaz Ali1, Haitham Bahaitham2, Raed Naebulharam2
1Department of Chemical and Materials Engineering, King Abdulaziz University, Rabigh, Saudi Arabia.
Bioresource Technology
|March 30, 2017
Summary
This study analyzed coconut shell waste pyrolysis using model-free and model-fitting methods. It revealed that nucleation and growth mechanisms govern the process, with varying activation energies for different components.
Area of Science:
- Chemical Engineering
- Materials Science
- Biomass Conversion
Background:
- Coconut shell waste presents a significant disposal challenge.
- Pyrolysis offers a sustainable route for valorizing biomass waste.
- Understanding pyrolysis kinetics is crucial for optimizing energy recovery.
Purpose of the Study:
- To compare model-free and model-fitting methods for analyzing coconut shell pyrolysis.
- To determine the reaction kinetics and mechanisms governing the pyrolytic conversion of coconut shell.
- To elucidate the thermal degradation behavior of different pseudo-components within coconut shell.
Main Methods:
- Differential and integral iso-conversional methods were employed to estimate apparent activation energy.
- Kissinger's method was used to determine the average activation energy of pseudo-components.
- Model-free and model-fitting approaches were combined to analyze pseudo-lignin decomposition.
Main Results:
- Apparent activation energy increased with pyrolytic conversion.
- The reaction model f(α)=(1-α)4·[-ln(1-α)]0.53 indicated nucleation and growth mechanisms.
- Pseudo-lignin exhibited slower decomposition kinetics compared to pseudo-cellulose and pseudo-hemicellulose.
- Activation energies for dehydration, pseudo-cellulose, and pseudo-hemicellulose were 21.9, 106.4, and 108.6 kJ/mol, respectively.
Conclusions:
- Solid-state pyrolysis of coconut shell waste is controlled by nucleation and growth mechanisms.
- The thermal degradation of coconut shell involves multiple overlapping peaks with distinct kinetic parameters.
- Pseudo-lignin requires a broader temperature range and exhibits higher activation energy for decomposition.
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