title: A precise study on effects that trigger alkaline hemicellulose extraction efficiency.
abstract: The conversion of paper-grade pulps into dissolving pulps requires efficient strategies and process steps to remove low-molecular noncellulosic macromolecules generally known as hemicelluloses. Current strategies include alkaline extractions and enzymatic treatments. This study focused on the evaluation of extraction efficiencies in alkaline extractions of three economically interesting hardwood species: beech (Fagus sylvatica), birch (Betula papyrifera), and eucalyptus (Eucalyptus globulus). Substrate pulps were subjected to alkaline treatments at different temperatures and alkalinities using white liquor as the alkali source, followed by analyses of both pulps and hemicellulose-containing extraction lyes. The extracted hardwood xylans have strong potential as an ingredient in the food and pharmaceutical industries. Subsequent analyses revealed strong dependencies of the extraction efficiencies and molar mass distributions of hemicelluloses on the process variables of temperature and effective alkalinity. The hemicellulose content of the initial pulps, the hardwood species, and the type of applied base played minor roles.
authors.affiliation: Kompetenzzentrum Holz GmbH, Altenberger Str. 69, A-4040 Linz, Austria.
authors.forename: Christian
authors.initials: C
authors.lastname: Hutterer
authors.affiliation: Lenzing AG, Werkstraße 1, A-4860 Lenzing, Austria.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Schild
authors.affiliation: Universität für Bodenkultur Wien, Department für Chemie, Muthgasse 18, A-1190 Wien, Austria. Electronic address: antje.potthast@boku.ac.at.
authors.forename: Antje
authors.initials: A
authors.lastname: Potthast
mesh_terms: D008970:Molecular Weight; D010209:Paper; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification*; D052616:Solid Phase Extraction / Q000379:methods*; D013696:Temperature; D014934:Wood / Q000737:chemistry*; D014990:Xylans / Q000737:chemistry
chemical_list: D011134:Polysaccharides; D014990:Xylans; C007916:hemicellulose
keywords: Alkaline degradation; Cold caustic extraction; Molar mass; Sugar composition; Xylan product