Saccharide Alterations in Spruce Wood Due to Thermal and Accelerated Aging Processes

Area of Science:

• Wood Science
• Polymer Chemistry
• Materials Science

Background:

• Thermally modified wood (Thermowood) offers enhanced durability but its end-of-life utilization requires understanding polysaccharide changes.
• Investigating polysaccharide alterations is crucial for sustainable resource management and novel material development.

Purpose of the Study:

• To analyze the impact of thermal modification and accelerated aging on spruce wood polysaccharides.
• To evaluate the potential for utilizing aged, thermally treated wood for cellulose and hemicellulose extraction.

Main Methods:

• Spruce wood samples underwent thermal treatment (160-210 °C) followed by accelerated aging.
• Analysis involved wet chemistry, High-Performance Liquid Chromatography (HPLC), X-ray Diffraction (XRD), Size Exclusion Chromatography (SEC), and Fourier-Transform Infrared Spectroscopy (FTIR).

Main Results:

• Thermal treatment primarily degraded hemicelluloses, with increased cellulose yield and crystallinity at 210 °C due to aromatic compound binding.
• Higher temperatures degraded the cellulose crystal lattice, and the degree of polymerization decreased for both cellulose and hemicelluloses.
• Accelerated aging showed no significant effect on the polysaccharide structural changes induced by thermal treatment.

Conclusions:

• Thermal modification significantly alters wood polysaccharides, primarily affecting hemicelluloses and cellulose crystallinity.
• The observed changes suggest that thermally modified wood, even after aging, can be a viable source for industrial cellulose and hemicellulose recovery.
• Understanding these polysaccharide transformations is key to optimizing the circular economy potential of wood products.