Alkaline steeping of dissolving pulp. Part II: Soluble compounds in the press lye

作者：Mozdyniewicz Danuta Joanna; Schild Gabriele; Sixta Herbert^*

来源：Cellulose, 2014, 21(4): 2889-2900.

DOI：10.1007/s10570-014-0291-6

• Degradation products
• Dissolving pulp
• Hemicellulose
• Hydroxy acids
• Steeping
• Viscose process

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 degrees 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 beta-fraction. With extended treatment times and temperatures, the proportion of xylan in the beta-fraction is increased. However, the molar mass distribution and the amount of 4-O-methylglucuronic acid in the beta-fraction revealed no clear trend as a function of the treatment conditions. In total 13 hydroxy acids were identified in the acid soluble gamma-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.

• 出版日期2014-8