| dc.description.abstract | The pyrolysis of jack pine bark, jack pine sawdust,
and cellulose powder has been studied by thermogravimetric
(TG), and isothermal weight-loss methods in both inert and
oxidizing atmospheres. The effects of particle size,
solvent extraction, and a number of additives on the low
temperature pyrolysis of jack pine bark have also been
examined.
Samples were analysed by low-temperature gas adsorption
and the bark characterized by infrared spectroscopy.
Residues were analysed for CHN contents and structural changes
which occurred on heating were examined by scanning electron
microscopy.
The TG characteristics of bark were affected only
slightly by particle size, solvent extraction, and additives.
Isothermal decomposition data for bark and sawdust were
similar and closely resembled established kinetic expressions
associated with inorganic decomposition reactions controlled
by diffusion processes. The data for cellulose were described
by at least tv70 kinetic stages with the second or principal
region resembling a standard kinetic expression for a phaseboundary
controlled reaction.
The pyrolysis data were found to fit a reaction rate
compensation curve, often associated with oxidation processes
but more generally with heterogeneous catalytic reactions. The compensation curve also relates the kinetic parameters
found by other workers for a large variety of wood-derived
materials. | |
