Collect. Czech. Chem. Commun. 2007, 72, 307-320

Production and Refining of Soluble Products from Eucalyptus globulus Glucuronoxylan

María José Vázquez, José Luis Alonso, Herminia Domínguez and Juan Carlos Parajó*

Department of Chemical Engineering, University of Vigo (Campus Ourense), Polytechnical Building, As Lagoas, 32004 Ourense, Spain


Milled Eucalyptus globulus wood samples were subjected to hydrothermal treatment under a variety of operational conditions in order to cause the hydrolytic degradation of glucuronoxylan. Liquors contained both hemicellulose-derived products (soluble products from xylan, mainly corresponding to substituted oligosaccharides and monosaccharides) and non- saccharide compounds. Liquors obtained under selected conditions were concentrated and subjected to ethyl acetate extraction (3 steps) and ion exchange (with Amberlite IRA 400 or Amberlite IRA 96) to decrease the content of non-saccharide components. The various streams involved in the whole process were assayed for composition, and material balances were formulated for the best results. The highest purification degree was obtained with Amberlite IRA 400, which led to a final isolate (consisting of monosaccharides, substituted oligosaccharides and non-volatile, non-saccharide components) containing 92.2 wt.% of saccharides and 7.76 wt.% of non-saccharide components (mainly phenolic compounds).

Keywords: Autohydrolysis; Eucalyptus globulus; Hemicelluloses; Glucuronoxylan; Purification; Refining; Xylooligosaccharides; Wood hydrothermal treatment; Hydrolysis.

References: 23 live references.