Chemical Analysis of Densification, Drying, and Heat Treatment of Scots pine (Pinus sylvestris L.) through a Hot-Pressing Process

• Main Authors: Lili Li, Ximing Wang, Feiyu Wu
• Format: Article
• Language: English
• Published: North Carolina State University 2016-03-01
• Series: BioResources
• Subjects: Hot-pressing; Heat treatment; Chemical changes
• Online Access: http://ojs.cnr.ncsu.edu/index.php/BioRes/article/view/BioRes_11_2_3856_Li_Chemical_Analysis_Densification_Drying_Heat-Treatment

This study investigated a new potential hot-pressing method for wood modification, in which densification, drying, and heat-treatment were carried out in sequence. The effects of heat treatment on the chemical components of wood were evaluated. The specimens were treated at different temperatures (180 to 220 °C) for 2 to 5 h. Holocellulose, α-cellulose, and lignin were extracted from the treated and untreated milled wood. The changes in these components were analyzed by thermogravimetry (TG) and Fourier-transform infrared spectroscopy (FTIR). Due to its amorphous structure, most hemicelluloses were degraded when it was exposed to 220 °C for 3 h and to 200 °C for 5 h. Conversely, the lignin contents increased continuously throughout the treatment due to the loss of polysaccharides and the formation of cross-links. Because of the crystallinity, α-cellulose degradation was slight. According to the analysis of functional groups, FTIR showed treated wood was more hydrophobic than the untreated one.