ABSTRACT
The thermal decomposition of wood can be influenced by numerous factors including obviously temperature, wood composition, amount of oxygen present, and amount of water vapor available during actual pyrolysis. Through the use of differential thermal analysis it has been demonstrated that during the thermal degradation of wood an endothermal maximum occurs at 120 to 150°C due to the evaporation of water. In general, hemicellulose thermally decomposes to yield furan and its derivatives, as well as a series of aliphatic carboxylic acids. Cellulose is the next major wood component to undergo thermal decomposition and it appears to occur by two distinct pathways, with one pathway being prevalent at lower temperatures, and the other pathway dominating at temperatures above 300°C. The thermal degradation products of wood can be grouped into the combustible volatiles, tar, and char. The presence or absence of air also has a significant effect on the thermal reactivity of wood.
