Molecular Mass Distribution of Lignin from the Alkaline Pulping of Hardwood,Softwood, and Wheat Straw |
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| Authors: | Hannu Pakkanen Raimo Alén |
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| Affiliation: | Laboratory of Applied Chemistry, Department of Chemistry , University of Jyv?skyl? , Finland |
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| Abstract: | Abstract The behavior of lignin during kraft (hardwood, softwood, and wheat straw) and soda-AQ (wheat straw) pulping was studied, mainly in terms of delignification degree and molecular mass distribution (MMD). In the initial delignification phase (at 140°C for 15–60 min), a prominent part of the dissolved softwood kraft lignin (18–25 g/L, MM mostly > 3,000 Da) was found in the liquid phase of chip cavities, rather than in the external bulk black liquor (5–7 g/L, MM mostly < 3,000 Da). The maximum weight average MM values (  | |
| Keywords: | Lignin molecular mass delignification alkaline pulping hardwood softwood wheat straw |
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