Modelling the thermal decompositions of wood and leaves under a nitrogen atmosphere

✍ Scribed by N. A. Liu; W. C. Fan

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 126 KB
• Volume: 22
• Category: Article
• ISSN: 0308-0501
• DOI: 10.1002/(sici)1099-1018(1998050)22:3<103::aid-fam638>3.0.co;2-g

✦ Synopsis

The thermal decomposition of six different samples of wood and leaves in nitrogen has been studied by using dynamic thermogravimetry. In the experiments two main weight loss processes took place and the total weight loss at 500°C was over 95% in all six cases. By means of the Doyle method, the two processes were found to fit most closely the plot for the second-order equation in the form d /dt ‫؍‬ k(1! ) 2 , and each of the weight loss processes was found to be controlled, respectively, by two dominant reactions as the temperature increases. It was inferred that competing reactions occur during the overall temperature interval for all the six samples. By comparing the activation energies using this model with those by the method of Moll et al., and by comparing the experimental and theoretical thermogravimetric curves, the 'second-order' model was tested to be able to predict the weight loss processes of the samples with very good accuracy. It can be concluded that the 'second-order' kinetic model acts much better than the conventionally adopted first-order model.