This work describes the comprehensive characterization of the degradation products obtained after the alkaline steeping of dissolving pulp. Total chlorine free bleached beech sulfite pulp was treated with 18 % sodium hydroxide at different temperatures (40, 50 and 60 °C) for time periods of up to 80 h. After the removal of the insoluble cellulose, the remaining alkali solution was treated with sulfuric acid to precipitate the β-fraction. With extended treatment times and temperatures, the proportion of xylan in the β-fraction is increased. However, the molar mass distribution and the amount of 4-O-methylglucuronic acid in the β-fraction revealed no clear trend as a function of the treatment conditions. In total 13 hydroxy acids were identified in the acid soluble γ-fraction, of which glucoisosaccharinic, glycolic, lactic and xyloisosaccharininc acids were among the most abundant hydroxy acids representing the degradation products from C6- and C5-sugars.
Fields of Expertise
- Advanced Materials Science
Treatment code (Nähere Zuordnung)
- Basic - Fundamental (Grundlagenforschung)