Chemical groups and structural characterization of lignin via thiol-mediated demethylation

  • Authors: Hu, Lihong; Pan, Hui; Zhou, Yonghong; Hse, Chung-Yun; Liu, Chengguo; Zhang, Baofang; Xu, Bin
  • Publication Year: 2014
  • Publication Series: Scientific Journal (JRNL)
  • Source: Journal of Wood Chemistry Technology 34(2):122-134
  • DOI: 10.1080/02773813.2013.844165

Abstract

A new approach to increase the reactivity of lignin by thiol-mediated demethylation was investigated in this study. Demethylated lignin was characterized by the changes in its hydroxyl and methoxyl groups, molecular weight, and other properties using titration and spectroscopy methods including FT-IR, 1H NMR, UV,and GPC. The total, phenolic, and aliphatic hydroxyl contents in lignin increased while the methoxyl content decreased after demethylation reaction, which indicated the occurrence of demethylation reaction. The results from FT-IR and UV analysis also indicated that the kraft lignin in this study contains mainly guaiacyl moiety and demethylated lignin has a higher guaiacyl content than original lignin. The average molecular weight of lignin decreased after demethylation reaction due to the cleavage of ether linkages in lignin macromolecules. No severe degradation of lignin was observed during the demethylation reaction.

  • Citation: Hu, Lihong; Pan, Hui; Zhou, Yonghong; Hse, Chung-Yun; Liu, Chengguo; Zhang, Baofang; Xu, Bin 2014. Chemical groups and structural characterization of lignin via thiol-mediated demethylation. Journal of Wood Chemistry Technology. 34(2):122-134. 13 p.
  • Keywords: Biomaterials, demethylation, odorless thiol, nucleophilic substitution, lignin reactivity
  • Posted Date: September 17, 2014
  • Modified Date: May 11, 2015
  • Print Publications Are No Longer Available

    In an ongoing effort to be fiscally responsible, the Southern Research Station (SRS) will no longer produce and distribute hard copies of our publications. Many SRS publications are available at cost via the Government Printing Office (GPO). Electronic versions of publications may be downloaded, printed, and distributed.

    Publication Notes

    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
    • Our online publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact the SRS webmaster if you notice any errors which make this publication unusable.
    • To view this article, download the latest version of Adobe Acrobat Reader.