|
authors |
Marques, AP; Evtuguin, DV; Magina, S; Amado, FML; Prates, A |
|
nationality |
International |
|
journal |
JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY |
|
author keywords |
Eucalyptus globulus; ESI-MS; NMR; lignosulphonates; structure; sulphite pulping; sulphite spent liquor |
|
keywords |
MASS-SPECTROMETRY; FINE CHEMICALS; LIGNIN; VANILLIN; BEHAVIOR |
|
abstract |
The structure of lignosulphonates (LS) from acidic magnesium-based sulphite pulping of Eucalyptus globulus wood has been studied. LS from thin and thick spent liquors were purified by dialysis and characterised by 1D/2D Nuclear Magnetic Resonance (NMR) and Electrospray Ionization Mass Spectrometry (ESI-MS). It was suggested that major part of LS is comprised of partially sulphonated low molecular weight oligomers formed via extensive cleavage of -O-4 bonds in eucalypt lignin upon sulphite pulping. More than ten types of LS structures derived from different lignin structural units have been identified. A significant proportion of LS ( 20%) is comprised by monomeric compounds, mainly 4-allyl-2,6-dimethoxyphenyl- -sulphonic and 4-propyl-2,6-dimethoxyphenyl-, -disulphonic acids. LS revealed partial degradation during the thin liquor evaporation leading to cleavage of ether and carbon-carbon linkages in the side chain and to the increasing of the condensation degree. |
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publisher |
TAYLOR & FRANCIS INC |
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issn |
0277-3813 |
|
year published |
2009 |
|
volume |
29 |
|
issue |
4 |
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beginning page |
337 |
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ending page |
357 |
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digital object identifier (doi) |
10.1080/02773810903207762 |
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web of science category |
Materials Science, Paper & Wood |
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subject category |
Materials Science |
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unique article identifier |
WOS:000274364200006
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