Beech wood, hemicellulose

The peak at 3330 cm (Fig. la) corresponds to the mixed hydroxyl groups from cellulose and hemicelluloses present in wood filler. The peak around 1076 cm recorded for beech wood sawdust filler is a characteristic peak which can be attributed to the C-0 stretching in cellulose, and hemicelluloses components, respectively. The peak noticed around 1643 cm is characteristic to the absorption of conjugated carbonyl group C=0 of lignin in beech wood sawdust filler. 

Hemicelluloses extracted flora a hardwood and softwood source, namely beech wood sulphite pulp (BS) (19) and Eucalyptus prehydrolysis itraft pulp (EK) (20) respectively, were characterized and the results were compared to the press lye obtained firom the viscose process. Table I contains the standard specification of the starting materials. The characteristic data of press iye (PL) are summarized in Table II. 

Japanese beech wood Temperature 170-290°C Residence time 30 min Pressure 20 MPa In both batch and semi-batch conversions, saccharides yield obtained from cellulose and hemicelluloses was maximum. Lu and Saka, 2010... 

For the study of soluble polysaccharides, a treatment with diluted TFA is sufficient and the reaction time can be kept short (7). Soluble polysaccharides of wood are separated from holocellulose by extraction with alkali. Wise et al. (10) term the extract with 5% KOH polyoses (hemicelluloses) A. Polyoses A can be hydrolyzed completely with 2N TFA within 1 hr. The chromatograms of the hydrolysates of polyoses A from spruce and beech holocelluloses recorded with a sugar analyzer (Biotronik ZA 5100) are shown in Figure 1. 

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