Abstract
Interlaboratory tests for chemical characterisation of sulphur-free lignins were performed by five laboratories to develop useful analytical protocols, which are lacking, and identify quality-related properties. Protocols have been established for reproducible determination of the chemical composition and functional groups, such as phenolic hydroxyl and carboxyl groups of alkaline lignins from annual fibre sources. The lignins studied, were precipitated from black liquors of alkaline pulping of annual fibre crops, flax, hemp and straw. The total (Klason and acid soluble) lignin contents of these lignins range between 83 and 97%. Contaminants may be present, such as sugar residues (
Original language | English |
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Pages (from-to) | 271-281 |
Journal | Industrial Crops and Products |
Volume | 19 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2004 |
Keywords
- hydroxyl-groups
- milled wood
- spectroscopy
- acids
- ftir