thumbnail

Solid-state 13C nuclear magnetic resonance studies of coalified gymnosperm xylem tissue from Australian brown coals

Organic Geochemistry

By:
, , , and

Links

  • The Publications Warehouse does not have links to digital versions of this publication at this time
  • Download citation as: RIS

Abstract

We report here on the use of solid-state 13C nuclear magnetic resonance (NMR) spectroscopy to contrast the average chemical composition of modern degraded gymnosperm woods with fossil gymnosperm woods from Australian brown coals (Miocene). We first established the quantitative nature of the NMR techniques for these samples so that the conventional solid-state 13C NMR spectra and the dipolar dephasing NMR spectra could be used with a high degree of reliability to depict average chemical compositions. The NMR results provide some valuable insights about the early coalification of xylem tissue from gymnosperms. Though the cellulosic components of wood are degraded to varying degrees during peatification and ensuing coalification, it is unlikely that they play a major role in the formation of aromatic structures in coalified woods. The NMR data show that gynmosperm lignin, the primary aromatic contribution to the coal, is altered in part by demethylation of guaiacyl-units to catechol-like structures. The dipolar dephasing NMR data indicate that the lignin also becomes more cross-linked or condensed. ?? 1989.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Solid-state 13C nuclear magnetic resonance studies of coalified gymnosperm xylem tissue from Australian brown coals
Series title:
Organic Geochemistry
Volume
14
Issue:
2
Year Published:
1989
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
Organic Geochemistry
First page:
145
Last page:
155
Number of Pages:
11