The influence of vacuum heat treatment on the pore structure of earlywood and latewood of larch
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Bailing Sun
Abstract
To investigate the changes in the pore structure of earlywood and latewood (EW and LW) in larch during the heat treatment process, this study applied nitrogen adsorption and mercury intrusion porosimetry (MIP) to measure wood pore characteristics. Wood samples were heat treated within a vacuum atmosphere at temperatures between 180 and 220 °C for 6 h. Analysis conducted on nitrogen adsorption isotherms indicated that the micropores and mesopores in the cell walls were present in both untreated and heat-treated EW and LW, and that the mesopores appeared as slit-shaped pores. More pores were detected in EW compared to LW, and these primarily absorbed in the range of 1.5–4 nm. Compared with the untreated wood, the total pore volume of treated wood decreased with increasing temperatures, with decreased pore volumes at 220 °C of 63 and 42% for EW and LW, respectively. The MIP results showed a greater porosity of EW compared to LW. Compared with the untreated wood, the porosity of heat-treated EW and LW first increased with increasing temperature, and then decreased at 220 °C. For treatment temperatures lower than 200 °C, heat treatment increased the proportion of macropores with pore sizes in the ranges of 100–1000 nm and 10,000–40,000 nm.
Funding source: Study on the thermal response characteristics of wood cell wall and its effect on the self-regulation mechanism of cell lumen deformation
Award Identifier / Grant number: Chinese National Natural Science Foundation (No. 31)
Acknowledgments
We would like to express our gratitude for the assistance on nitrogen adsorption testing given by Mrs. Guo Juan at the Research Institute of Wood Industry, Chinese Academy of Forestry.
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Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
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Research funding: The authors gratefully acknowledge the support of the Chinese National Natural Science Foundation (no. 31901244).
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Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
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© 2022 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Original Articles
- Intra-species variation in maximum moisture content, cell-wall density and porosity of hardwoods
- Fractal dimension of wood pores from pore size distribution
- Fatigue testing of wood up to one billion load cycles
- The influence of vacuum heat treatment on the pore structure of earlywood and latewood of larch
- The relationship between color and mechanical properties of heat-treated wood predicted based on support vector machines model
- Effect of water/moisture migration in wood preheated by hot press on sandwich compression formation
- Quercetin-grafted modification to improve wood decay resistance
- Organosolv delignification of birch wood (Betula pendula): DMSO/water pulping optimization
- Alkali lignin as a pH response bifunctional material with both adsorption and flocculation for wastewater treatment
- Evaluation of the mechanical properties of different parts of bending bamboo culm by nanointendation
Articles in the same Issue
- Frontmatter
- Original Articles
- Intra-species variation in maximum moisture content, cell-wall density and porosity of hardwoods
- Fractal dimension of wood pores from pore size distribution
- Fatigue testing of wood up to one billion load cycles
- The influence of vacuum heat treatment on the pore structure of earlywood and latewood of larch
- The relationship between color and mechanical properties of heat-treated wood predicted based on support vector machines model
- Effect of water/moisture migration in wood preheated by hot press on sandwich compression formation
- Quercetin-grafted modification to improve wood decay resistance
- Organosolv delignification of birch wood (Betula pendula): DMSO/water pulping optimization
- Alkali lignin as a pH response bifunctional material with both adsorption and flocculation for wastewater treatment
- Evaluation of the mechanical properties of different parts of bending bamboo culm by nanointendation
