Birch wood pre-hydrolysis vs pulp post-hydrolysis for the production of xylan-based compounds and cellulose for viscose application

No Thumbnail Available
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
Date
2018-06-15
Major/Subject
Mcode
Degree programme
Language
en
Pages
10
212-221
Series
Carbohydrate Polymers, Volume 190
Abstract
Hydrothermal treatments of birch wood and kraft pulp were compared for their ability to extract the xylan and produce viscose-grade pulp. Water post-hydrolysis of kraft pulp produced a high-purity cellulosic pulp with lower viscosity but higher cellulose yield than traditional pre-hydrolysis kraft pulping of wood. Post-hydrolysis of pulp also increased the crystallite dimensions and degree of crystallinity in cellulose, and promoted a higher extent of fibril aggregation. The lower specific surface area in post-hydrolyzed pulps, derived from their larger fibril aggregates, decreased the accessibility of –OH groups. However, this lower accessibility did not seem to decrease the pulp reactivity to derivatizing chemicals. In the aqueous side-stream, the xylose yield was similar in both pre- and post-hydrolysates, although conducting post-hydrolysis of pulp in a flow-through system enabled the recovery of high purity and molar mass (∼10 kDa) xylan for high-value applications.
Description
Keywords
Cellulose, Dissolving pulp, Hydrothermal treatment, Viscose, Xylan
Other note
Citation
Borrega, M, Larsson, P T, Ahvenainen, P, Ceccherini, S, Maloney, T, Rautkari, L & Sixta, H 2018, ' Birch wood pre-hydrolysis vs pulp post-hydrolysis for the production of xylan-based compounds and cellulose for viscose application ', Carbohydrate Polymers, vol. 190, pp. 212-221 . https://doi.org/10.1016/j.carbpol.2018.02.064