Journal article
The effects of supercritical CO 2 on the bending properties of four refractory wood species
Forest Products Journal, Vol.50(11-12), pp.85-93
2000
Abstract
The effects of three supercritical fluid (SCF) treatment parameters on the bending properties and development of treatment defects were studied in Douglas-fir, yellow-poplar, western redcedar, and Engelmann spruce. Two rates of pressurization (0.34 and 3.44 MPa/min.), two treatment pressures (10.34 and 20.69 MPa), and two venting rates (0.34 and 3.44 MPa/min.) were examined on small, clear specimens of each species, using one treatment temperature (60°C) and one treatment time (30 min.). Supercritical treatment of yellow-poplar produced no significant reductions of bending properties. Bending properties of Douglas-fir appeared to increase after SCF treatment, butthese increases were due to differences in mean specific gravities between treatments. Bending properties in western redcedar and Engelmann spruce were reduced significantly after SCF treatment. Western redcedar specimens showed up to 23.1 percent reduction of modulus of rupture (MOR), 13.7 percent reduction in modulus of elasticity (MOE), and 31.0 percent reduction in work-to-maximum-load (WML) after SCF treatment. Engelmann spruce properties declined 10.8 to 21.6 percent in MOR, 16.0 to 21.4 percent in MOE, and 7.2 to 29.0 percent in WML after SCF treatment. Rapid rates of venting produced the most significant reductions in bending properties for western redcedar, while Engelmann spruce was affected by both slow and rapid rates of pressurization and venting. The results indicate that SCF treatments, while effective for treating refractory wood species, must be used with some caution to avoid inducing negative effects on bending properties.
Details
- Title
- The effects of supercritical CO 2 on the bending properties of four refractory wood species
- Authors
- M E Anderson (Author)R J Leichti (Author)Jeffrey J Morrell (Author)
- Publication details
- Forest Products Journal, Vol.50(11-12), pp.85-93
- Publisher
- Forest Products Society
- Date published
- 2000
- ISSN
- 0015-7473
- Organisation Unit
- University of the Sunshine Coast, Queensland; National Centre for Timber Durability and Design Life
- Language
- English
- Record Identifier
- 99450647002621
- Output Type
- Journal article
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