Effect of Inorganic Salts on Pyrolysis of Wood, Cellulose, and Lignin Determined by Differential Thermal Analysis
Abstract
Differential thermal analysis was conducted in both helium and oxygen atmospheres on the thermal decomposition of wood, cellulose, and lignin, untreated and treated with 2 and 8 percent by weight of eight inorganic salts and an acid. Thermograms were obtained for the temperature ranges for endothermic and exothermic reactions, for the temperatures of maximum heat absorption or release, and for the heat intensities. These data combined with results of a previous work utilizing thermogravimetric analysis provide additional information on the characteristics of thermal decomposition. In particular, these data show that the net heat of pyrolysis for untreated and treated cellulose is endothermic. The heat of pyrolysis for both wood and lignin is initially endothermic and later becomes exothermic. However, the net exothermic heat of pyrolysis for wood is only about 2 percent of the heat of combustion. The heat of combustion from wood is released by flaming of the volatiles with a maximum release at about 310 deg C and a glowing of the solids with a second maximum release at about 440 deg C. The influence of the several types of effective and ineffective fire-retardant salts on the initial temperature of volatilization, rate of decomposition and heat release, transition temperatures of volatilization and heat release, and maximum heat intensities are also related by this work to theories that have been developed concerning the retarding of flaming and glowing reactions of wood and its components.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1968
- Accession Number
- AD0664559
Entities
People
- Herbert W. Eickner
- Walter K. Tang
Organizations
- Forest Products Laboratory