Lignin solubility

The significance of phenoxy anions is well recognized in the isolation of kraft and other water-insoluble technical lignins by acid precipitation. The ioniza tion of phenoHc hydroxyl groups coupled with the reduction of molecular size renders native lignin soluble in the aqueous pulping solution, thus enabling its separation from the polysaccharide components of wood. 

Acetylated lignins, molecular weight distribution, 87,89-94/951,96 Acetylation, effect on lignin solubility, 284... 

From an inspection of the values in Table 7.2.2, it is clear that the phenolic content of lignin decreases in the order kraft lignin kraft pulp > wood, a trend which underscores the significance of aryl ether cleavage in delignification and of the effect of the phenolic hydroxyl groups on lignin solubility. 

Scientific darnel Common Name Carbohydrate Klason Lignin Solubility Ash... 

Scientific NamelCommon Name Carbohydrate Cross and Bevan Alpha Cellu- Cellu- Pento-lose lose sans Klason Lignin Solubility ... 

This initial oxidative depolymerization of cellulose evidently opens up the wood cell wall structure so that cellulolytic and hemi-cellulolytic enzymes can reach their substrates despite the presence of lignin. Solubility of wood in 1% NaOH increases markedly on brown-rot attack IS) and reflects cellulose depolymerization and the opening up of the wood structure. 

A study on lignin solubility in ionic liquids has shown that up to 20 wt% kraft wood lignin can be dissolved in 1,3-dimethylimidazolium methylsulfate, l-butyl-3-methylimidazolium methylsulfate and l-hexyl-3-methylimidazolium... 

Cellulose celluloses Pectin Lignin solubles wax Moisture Ash... 

A fraction (2% based on oven-dried weight) of Klason lignin soluble in 0.7% sodium chlorite solution and containing nearly all (5.3%) the methoxyl groups was associated with the middle lamella just outside the surface of the fiber. 

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