Upgrading of commercial pulps to high-purity dissolving pulps by an ionic liquid-based extraction method

Research output: Contribution to journalArticleScientificpeer-review


  • Petra Wollboldt
  • Michael Strach
  • Axel Russler
  • Stepanka Jankova
  • Herbert Sixta

Research units

  • Kompetenzzentrum Holz GmbH, Wood K plus
  • Glanzstoff Industries GmbH


In the course of the Ioncell-P process, hemicelluloses are extracted from wood pulps by a mild treatment with an ionic liquid (IL) water mixture, and the result is a high-purity dissolving pulp. The aim of the present work is to study the influence of pulp origin concerning different wood species and pulping processes on the resulting pulp purity and yield after extraction with IL/water, while the IL is 1-ethyl-3-methylimidazolium acetate ([emim][OAc]). The raw materials were chosen from commercial alkaline kraft and acid sulfite paper and dissolving pulps prepared from both hardwood (HW) and softwood (SW). The extraction was followed by a filtration step to separate the cellulose and the hemicellulose fractions. The hemicelluloses were precipitated from the IL/water filtrate. In general, the Ioncell-P process proved to be more selective toward the removal of xylan as compared to glucomannan indicating that HW pulps are easier to purify than those of SW. It was possible to reach high alpha pulp qualities by the extraction process.


Original languageEnglish
Pages (from-to)611-618
Number of pages8
Issue number7-8
Publication statusPublished - 26 Jul 2017
MoE publication typeA1 Journal article-refereed

    Research areas

  • cellulose purification, dissolving pulp, hemicellulose extraction, ionic liquid

ID: 14386592