Wood compositional changes during thermal modification follow a characteristic trajectory when mapped in a van Krevelen diagram. The trajectories of widely different wood species appear to merge into a single master curve, suggesting a common thermal modification chemistry shared by these wood species. The largest effect of thermal modification on the chemical composition can be explained by dehydration reactions, followed by decarboxylation reactions. A carbon valence electron donor–acceptor model is proposed, which relates the observed compositional changes to changes in polarity and redox character, which in turn are related to the characteristic hydrophobic and fungal resistance effects on wood by thermal modification.
AhajjiA, DioufPN, AlouiF, ElbakaliI, PerrinD, MerlinA, GeorgeB. 2009. Influence of heat treatment on antioxidant properties and colour stability of beech and spruce wood and their extractives.Wood Sci. Technol. 43(1–2): 69–83.
2.
ChaouchM, PétrissansM, PétrissansA, GérardinP. 2010. Use of wood elemental composition to predict heat treatment intensity and decay resistance of different softwood and hardwood species.Polym. Degrad. Stabil. 95(12): 2255–2259.
3.
ChaouchM. 2011. Effet de l'intensité du traitement sur la composition élémentaire et la durabilité du bois traité thermiquement : développement d'un marqueur de prédiction de la résistance aux champignons basidiomycètes. PhD thesis, Henri Poincaré University, Nancy, France.
4.
DingT, GuL, LiuX. 2011. Influence of steam pressure on chemical changes of heat-treated Mongolian pine wood.BioResources.6(2): 1880–1889.
5.
EngelundE, ThygesenL, SvenssonS, HillCAS. A critical discussion of the physics of wood–water interactions.2012. Wood Sci. Technol.DOI. 10·1007/s00226-012-0514-7
6.
FengelD, WegenerG. 1983. Wood: chemistry, ultrastructure, reactions. Berlin: Walter de Gruyter.
7.
HillC.A.S., 2006. Wood modification – chemical, thermal and other processes. Chichester: John Wiley & Sons.
8.
KrevelenDWvan. 1950. Graphical-statistical method for the study of structure and reaction processes of coal.Fuel. 29: 269–284.
9.
LamPS. 2011. Steam explosion of biomass to produce durable wood pellets. PhD thesis, University of British Columbia, Vancouver, Canada.
10.
LaRoweDE, van CappellenP. 2011. Degradation of natural organic matter: A thermodynamic analysis.Geochim. Cosmochim. Ac. 75: 2030–2042.
TjeerdsmaBF, BoonstraMJ, PizziA, TekelyP, MilitzH. 1998. Characterisation of thermally modified wood: reasons for wood performance improvement.Holz Roh-Werkst.56: 149–153.
17.
WillemsW, TauschA, MilitzH. 2010. Evidence for an antioxidant mechanism in the durability of high-pressure steam modified wood. Proc. 5th Eur. Conf. on Wood Modification ECWM5, (ed. Hill, C. A. S., Militz, H., and Andersons, B.). Riga: Latvian State Institute of Wood Chemistry, 127–134.
18.
WillemsW, MilitzH. 2013a. The water vapour sorption mechanism and its hysteresis in wood. In preparation.
19.
WillemsW, GérardinP, MilitzH. 2013b. The average carbon oxidation state of thermally modified wood correlated with durability against Basidiomyctes. In preparation.
20.
ZeitschKJ. 2000. The chemistry and technology of furfural and its many by-products. Sugar Series 13. Amsterdam: Elsevier.
