umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • 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
Properties of cellulose pulps and their influence on the production of a cellulose ether
Umeå University, Faculty of Science and Technology, Department of Chemistry.
Umeå University, Faculty of Science and Technology, Department of Chemistry.
Umeå University, Faculty of Science and Technology, Department of Chemistry.
2012 (English)In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 27, no 1, 24-34 p.Article in journal (Refereed) Published
Abstract [en]

Several grades of cellulose pulps were investigated for their influence on the product quality of a cellulose ether, ethyl hydroxyethyl cellulose (EHEC). The selection of the pulps was based on pulping process, original wood type and intrinsic viscosity. In total, five sulfite pulps and four sulfate pulps were chosen, of which all but one sulfate pulp were of dissolving grade. The physical and chemical properties of the pulps were analyzed as well as important qualitative parameters of the final product EHEC. The influence of pulp properties on EHEC quality was investigated by multivariate data analyses.Principal component analysis showed that due to the influence of all variables, the pulps aligned in groups in accordance to the selection criteria pulping process and wood type. Partial least square regression revealed that high gel formation in EHEC is explained by the pulp properties high intrinsic viscosity and high Mw in combination with high caustic absorption rate and high total caustic absorption. The amount of hemicelluloses, in particular xylose, also contributed to gel formation. High cloud point for an EHEC solution was explained by a high MSEO and low DSEt of the EHEC molecules, where in turn a high MSEO could be predicted by a high pore area, high PD and a low caustic absorption rate. A low DSEt could on the other hand be predicted by a low hemicellulose content and hence a high R18. In a separate model, the same pulp properties explaining MSEO and DSEt also predicted cloud point directly. Fock reactivity and viscose dope filterability, both test methods originating from the viscose manufacturing, were shown to predict cloud point but have low predictability on other EHEC quality parameters.The models achieved can thus be utilized to predict final EHEC product qualities for new pulps within the design set of the chosen pulps.

Place, publisher, year, edition, pages
2012. Vol. 27, no 1, 24-34 p.
Keyword [en]
Cellulose ether, Dissolving pulp, Ethyl-hydroxy-ethyl cellulose, Long fiber, Reactivity, Short fiber, Sulfate, Sulfite, Multivariate data analysis
National Category
Chemical Engineering
Identifiers
URN: urn:nbn:se:umu:diva-54004DOI: 10.3183/NPPRJ-2012-27-01-p024-034ISI: 000311019900003OAI: oai:DiVA.org:umu-54004DiVA: diva2:514869
Available from: 2012-04-11 Created: 2012-04-11 Last updated: 2017-12-07Bibliographically approved
In thesis
1. Characterization of cellulose pulps and the influence of their properties on the process and production of viscose and cellulose ethers
Open this publication in new window or tab >>Characterization of cellulose pulps and the influence of their properties on the process and production of viscose and cellulose ethers
2012 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Today’s market offers an ever-increasing range of cellulose pulps (derivative pulps) made fromvarious wood types through different delignification processes. Each pulp segment has its uniquecharacteristics, which makes it difficult for the producer of cellulose derivatives to choose the mostsuitable pulp for optimum processability and product quality. The objective of this study was toimprove knowledge of cellulose pulps and to describe how different pulp properties affectprocessability and quality in the production of viscose dope and cellulose ethers.Ten pulp samples were investigated, originating from both sulfite and sulfate processes, with highand low viscosities and with softwood and hardwood as raw material. The pulps were analyzed fortheir properties and then processed to viscose dope and a cellulose ether in two separate pilotfacilities. The intermediates in the viscose process as well as the quality of the viscose dope andcellulose ether were analyzed and the results correlated to pulp properties.Multivariate regression methods were applied to investigate the dominating physical and chemicalproperties of each pulp and pulp segment, and to study the use of spectroscopic analyses inpredicting pulp origin, concentration and composition of hemicelluloses as well as the content ofreducing end groups in cellulose. For the production of viscose dope, the models presented showedthe most important pulp properties for good cellulose reactivity and viscose filterability. In addition,the properties affecting gel formation, flocculation, degree of substitution and clarity in theproduction of cellulose ether were highlighted. The study also emphasized the need to supplementthe use of conventional analyses on pulps and viscose intermediates with other analytical methods,such as molecular weight distribution and carbohydrate analysis, to better predict the quality ofboth viscose dope and viscose fiber.The results of the present study could be useful to predict the origin and properties of new pulps, toreplace or supplement otherwise expensive pulp analyses, and to assess the impact of pulpproperties on the production of cellulose derivatives without extensive pilot-scale trials.

Place, publisher, year, edition, pages
Umeå: Umeå Universitet, 2012. 80 p.
Keyword
cellulose ether, dissolving pulp, ethyl hydroxyethyl cellulose, hardwood, multivariate data analysis, reactivity, softwood, sulfate, sulfite, viscose
National Category
Chemical Engineering
Identifiers
urn:nbn:se:umu:diva-54008 (URN)978-91-7459-406-5 (ISBN)
Public defence
2012-05-11, Naturvetarhuset, N320, Umeå Universitet, Umeå, 10:00 (English)
Opponent
Supervisors
Available from: 2012-04-20 Created: 2012-04-11 Last updated: 2012-04-20Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textNPPRJ

Search in DiVA

By author/editor
Strunk, PeterLindgren, ÅsaEliasson, Bertil
By organisation
Department of Chemistry
In the same journal
Nordic Pulp & Paper Research Journal
Chemical Engineering

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 464 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • 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