Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Extraction of hemicelluloses from fiberized spruce wood
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. Chalmers University of Technology, Sweden.
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.ORCID iD: 0000-0002-2900-4713
2015 (English)In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 117, 19-24 p.Article in journal (Refereed) Published
Abstract [en]

A novel mechanical pre-treatment method was used to separate the wood chips into fiber bundles in order to extract high molecular weight wood polymers. The mechanical pre-treatment involved chip compression in a conical plug-screw followed by defibration in a fiberizer. The fiberized wood was treated with hot water at various combinations of time and temperature in order to analyze the extraction yield of hemicelluloses at different conditions. Nearly 6 mg/g wood of galactoglucomannan was obtained at 90◦C/120min which was about three times more than what could be extracted from wood chips. The extracted carbohydrates had molecular weight ranging up to 60 kDa. About 10% of each of the extracted material had a molecular weight above 30 kDa. The extraction liquor could also be reused for consecutive extractions with successive increase in the extraction yield of hemicelluloses. 

Place, publisher, year, edition, pages
2015. Vol. 117, 19-24 p.
Keyword [en]
Spruce (Picea abies), Mechanical pre-treatment, Fiberized wood, Hemicelluloses, Galactoglucomannan
National Category
Polymer Technologies
Identifiers
URN: urn:nbn:se:kth:diva-158963DOI: 10.1016/j.carbpol.2014.09.050ISI: 000346263800003Scopus ID: 2-s2.0-84922311559OAI: oai:DiVA.org:kth-158963DiVA: diva2:781404
Funder
Knut and Alice Wallenberg Foundation
Note

QC 20150116

Available from: 2015-01-16 Created: 2015-01-16 Last updated: 2017-12-05Bibliographically approved
In thesis
1. Extraction of Polymeric Hemicelluloses from Spruce Wood
Open this publication in new window or tab >>Extraction of Polymeric Hemicelluloses from Spruce Wood
2015 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Hemicelluloses are one of the three main components of spruce wood and constitute about 20% of the wood material. During mechanical pulping, 5–10% of the hemicelluloses are accumulated in waste waters, whereas during chemical pulping 70–80% of the hemicelluloses are lost in process liquors. The concept of integrated forest biorefinery involves the development of methods to extract these hemicelluloses prior to pulping in order to produce value-­added products besides pulp. This thesis describes some of the feasible possibilities of extracting hemicelluloses from wood at a high molecular weight prior to pulping in addition to presenting a deeper understanding of their degradation under mild treatment conditions.

A major obstacle for the efficient extraction of hemicelluloses is the recalcitrance due to the network of lignin and polysaccharides. This network can be loosely opened by the use of enzymes and this improves the extraction of hemicelluloses. A chemical impregnation of the wood chips was performed to enhance the accessibility of the cell wall to enzymes. The ability of different additives to stabilize the hemicelluloses against peeling during the alkaline impregnation stage was also investigated in order to obtain a better yield in subsequent extraction.

Increasing the surface area and decreasing the mass transport length could also improve the yield of hemicelluloses extracted from wood. This was achieved with a mild mechanical pre-­treatment of wood chips using an impressafiner and a fiberizer. Polymers mainly consisting of galactoglucomannan with an average molecular weight of 30 kDa were extracted from fiberized wood with water.

Different pre-­treatment and extraction methods were combined to demonstrate the concept of material biorefinery based on wood.

The kinetics of degradation of spruce galactoglucomannan were studied under alkaline conditions. It was degraded in two phases at two different rates. A kinetic model was developed to fit the experimental data and to estimate the activation energies. 

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2015. 50 p.
Series
TRITA-CHE-Report, ISSN 1654-1081 ; 2015:4
National Category
Engineering and Technology
Research subject
Fibre and Polymer Science
Identifiers
urn:nbn:se:kth:diva-158966 (URN)
Public defence
2015-02-06, F3, Lindstedtsvägen 26, KTH, Stockholm, 10:00 (English)
Opponent
Supervisors
Note

QC 20150119

Available from: 2015-01-19 Created: 2015-01-16 Last updated: 2015-01-19Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Authority records BETA

Lindström, Mikael

Search in DiVA

By author/editor
Azhar, ShoaibHenriksson, GunnarTheliander, HansLindström, Mikael
By organisation
Wood Chemistry and Pulp TechnologyWallenberg Wood Science Center
In the same journal
Carbohydrate Polymers
Polymer Technologies

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 385 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf