Kraft lignin functional groups

Association of kraft lignin is mainly based on internal and external factors. The composition and the functional groups within the kraft lignin structure are important internal factors in determining the thermodynamic behavior of kraft lignin. The major groups are the aromatic ring (1/C9),... 

Lignin is a major component of plants where it serves as a binding agent for cellulose and other materials, and the kraft process of paper production, heating with alkali and sulfide, produces polyhydroxy phenolic, carboxylic acid, and sulfide functional groups in a soluble black liquor mixture [5]. Acidification precipitates this modified lignin as a powder, hereafter referred to as limin, a 20630% by product in the manufacture of paper. 

Asgari, R, and Argyropoulos, D. S., Fundamentals of oxygen delignification. Part II. Kinetics of functional group formation/elimination in residual kraft lignin, Can. J. Chem. 76, 1606-1615 (1998). 

FIGURE 11.34 Aqueous ozone treatment of kraft lignin. Changes in phenolic and total content of hydroxyl groups as a function of ozonation time. 

Table V. The Contents of Various Functional Groups (mmol/g Lignin) in the Degradation of Unbleached Softwood Kraft Pulp by P. cimabarbtm "...

Morck R, Yoshida H, Kringstad KP, Hatakeyama H (1986) Fractionation of kraft lignin by successive extraction with organic solvents-1. Functional groups, C13 NMR spectra and molecular weight distributions. Holzforschung 40 51... 

Functional Group. Lignin. Pine Lignin, kraft Process... 

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