| Abstract
| - Weight loss curves of thin layers (150 μm) of beech wood powder, measured for heating rates of1000 K/min and final temperatures in the range 573−708 K, show final char yields of 37−11%.The process is kinetically controlled and, for the most part, isothermal. A one-step global reaction,with E = 141.2 ± 15.8 kJ/mol and ln A = 22.2 ± 2.9 s-1, is a degradation mechanism capableof capturing the main features of the process. The thermogravimetric curves also allow theformation rate constants to be estimated for char and total volatiles (activation energies of 111.7± 14.3 and 148.6 ± 17.4 kJ/mol, respectively) and, once integrated byproduct distribution, thosefor liquids and gases (activation energies of 148 ± 17.2 and 152.7 ± 18.2 kJ/mol, respectively).A comparison is provided with pyrolysis mechanisms available in the literature.
|
