Abstract: | Samples of α-cellulose, containing 0.11–0.14% ash, were isothermally pyrolyzed in a fluidized bath in a nitrogen environment at 250–298°C. Results were reported in terms of volatilization (based on weight-loss measurements) and decomposition (in term of glucosan loss). The findings show three distinct stages of pyrolysis: (1) an initial period of rapid decomposition and weight loss; (2) a range in which both the volatilization and decomposition are of zero order; (3) a region in which the volatilization follows a first-order rate, leaving a char deposit which does not undergo further pyrolysis. The degree of decomposition and volatilization occurring during the zero-order phase increases with increasing temperature. A single activation energy of 42 kcal./mole describes both the decomposition and volatilization rates in the zero-order phase over the entire 250–298°C. range. |