Color and FTIR Analysis of Chemical Changes in Beech Wood (Fagus sylvatica L.) after Light Steaming and Heat Treatment in Two Different Environments

BioResources

Mihaela Campean¹  Anca Maria Varodi¹  Maria Cristina Timar²  Murat Hacibektasoglu² 

[1] Romania;Department of Wood processing and Wood products design, Faculty of Wood Engineering, Transilvania University of Brasov, Str. Universitatii 1, 500168 Brasov, Romania;

关键词: Steaming;    Heat treatment;    Beech wood;    FTIR;    Thermal treatments;    Color;    Chemical changes;   

DOI  :  10.15376/biores.11.4.8325-8343

来源: DOAJ

【 摘 要 】

Color and chemical changes were investigated in beech wood (Fagus sylvatica L.) following light steaming and further heat treatment for 2.5 h at 200 °C by two techniques (industrial ThermoWood versus a laboratory procedure in the presence of air). Colour changes were evaluated in the CIE Lab system, while Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR) investigation was employed to highlight and compare the associated chemical changes. Light steaming caused only minor chemical changes (limited hydrolysis of hemicelluloses) not ready detectable by FTIR. In contrast, heat treatments caused visible changes in the FTIR spectra, especially in the region 1800 to 1500 cm-1, consisting mainly in a clear decrease of the absorption band for conjugated carbonyls at 1643 cm-1 and a slight apparent increase of the absorption bands for lignin at 1506 and 1595 cm-1. A significant variation of the ratios of relevant absorption bands indicated complex chemical changes, including hydrolytic, oxidative, and condensation reactions. FTIR ratios and the mass loss values in the two heat treatments relate, both indicating a more advanced modification in the case of the ThermoWood process.

【 授权许可】

Unknown