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Licensed Unlicensed Requires Authentication Published by De Gruyter February 28, 2022

Chemical characteristics of heterogeneous lignocellulosic microfines prepared using the glycol ether-organosolv process: dissolution properties in an NaOH–urea aqueous solution

Kang-Jae Kim, Ji-Ae Ryu and Tae-Jin Eom
From the journal Holzforschung


In this study, heterogeneous lignocellulosic microfines (LCMFs) with different physicochemical properties were prepared from softwood by adjusting the reaction conditions of a glycol ether-organosolv process. The dissolution properties of heterogeneous LCMFs in an NaOH–urea aqueous solution were evaluated. As the reaction time increased, the yield and residual lignin content decreased. As the amount of chemical solution used to prepare LCMFs increased, more lignin than carbohydrates were removed, but the degree of polymerization (DP) was maintained. Finally, LCMFs with different residual lignin content, DP, and crystallinity were prepared via the glycol ether-organosolv process under various conditions. It was observed that lower the lignin content of heterogeneous LCMFs, higher were their solubilities in the NaOH–urea solution. The effect of DP on solubility was not significant; however, the hemicellulose content of LCMFs had a greater effect on their solubilities in the NaOH–urea aqueous solution than the sugar composition of hemicellulose. The chemical properties of lignin present in LCMFs had no significant effect on their solubilities in the NaOH–urea aqueous solution.

Corresponding author: Tae-Jin Eom, School of Forestry, Sciences and Landscape Architecture & Agricultural Science and Technology Research Institute, Kyungpook National University, 41566 Daegu, Republic of Korea, E-mail:

Funding source: Korea Forest Service

Award Identifier / Grant number: FTIS-2019149A00-2123-0301

Funding source: National Research Foundation of Korea

Award Identifier / Grant number: NRF-2019R1I1A1A01055532, NRF-2019R1I1A3A01051948

  1. Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  2. Research funding: This study was supported by the 2019 Individual Basic Science Program (NRF–2019R1I1A3A01051948 and NRF–2019R1I1A1A01055532) hosted by the National Research Foundation (NRF), Ministry of Science, ICT and Future Planning, Republic of Korea. Also, This study was carried out with the support of ‘R&D Program for Forest Science Technology (Project No. FTIS–2019149A00-2123-0301)’ provided by Korea Forest Service (Korea Forestry Promotion Institute).

  3. Conflict of interest statement: The authors declare no conflicts of interest regarding this article.


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Supplementary Material

The online version of this article offers supplementary material (

Received: 2021-05-10
Accepted: 2022-01-18
Published Online: 2022-02-28
Published in Print: 2022-06-27

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