Results 161 to 170 of about 924 (196)

High Temperature Leaching of Lignin From Unbleached Kraft Pulp Fibers

Journal of Wood Chemistry and Technology, 1983
Abstract When an unbleached kraft pulp was suspended in water at various temperatures between 20°C and 90°C the rate of the leaching of lignin from the fiber wall increased with the temperature. From 20°C to 70°C, the change in the intrafiber diffusion coefficient with temperature varied directly as the ratio of the absolute temperature to the ...
B. D. Favis, J. M. Willis, D. A. I. Goring   +2 more
exaly   +2 more sources

The Effect of Electrolytes on the Leaching of Lignin From Unbleached Kraft Pulp Fibers

Journal of Wood Chemistry and Technology, 1983
Abstract When an unbleached kraft pulp is suspended in aqueous solutions of electrolytes, the rate of leaching of lignin from the fiber wall is found to decrease with an increase in the ionic strength of the electrolyte. The effect was found to be greater with divalent ions (Mg++, Ca++, Zn++) than with a monovalent ion, Na+.
B. D. Favis, J. M. Willis, D. A. I. Goring   +2 more
exaly   +2 more sources

Residual Lignin in Uneleached Kraft Pulp. Part I.: -Allkalli-Extraction of Residual Lignin from Unbleached Kraft Pulp Solution-

Journal of Wood Chemistry and Technology, 1987
Abstract Unbleached kraft pulp containing 4.7% Klason lignin has been found to dissolve completely in several nonaqueous cellulose solvents. Extraction of the residual lignin in the unbleached kraft pulp from these solutions was attempted using several kinds of solvents for kraft lignin and hemicellulcoes.
Akira Isogai, Atsushi Ishizu, Junzo Nakano   +2 more
exaly   +2 more sources

Characterization of Residual Lignins Isolated from Unbleached and Semibleached Softwood Kraft Pulps

Journal of Wood Chemistry and Technology, 1987
Abstract Residual lignins in an unbleached and a semibleached softwood (Pinus taeda L.) kraft pulp were isolated by enzymatic hydrolysis of polysaccharides in the pulps. After purification, the residual lignins were characterized. A dissolved lignin was also isolated from the alkaline extraction spent liquor by acidification and characterized.
Hou-Min Chang
exaly   +2 more sources

Molecular Weight of Lignin Fractions Leached from Unbleached Kraft Pulp Fibers

Journal of Wood Chemistry and Technology, 1984
Abstract The molecular weights of lignin fractions leached from an unbleached kraft pulp were found to increase from 230,000 to 410,000 as washing of the pulp proceeded. The free diffusion coefficients for both a spherical and a disk-like conformation were calculated and were found to be seven orders of magnitude higher than the observed intrafiber ...
B. D. Favis, W. Q. Yean, D. A. I. Goring
exaly   +2 more sources

Chemical characterization of the surface layers of unbleached pine and birch kraft pulp fibres

Journal of Pulp and Paper Science, 1996
The content of wood polymers in different morphological parts of unbleached pine and birch kraft pulp was studied using a mechanical peeling technique. The relative distribution of hemicelluloses and cellulose in the surface material of the pine kraft fibres was similar to that in the whole fibres.
Suurnäkki, Anna, Heijnesson, Anette, Buchert, Johanna, Viikari, Liisa, Westermark, Ulla   +5 more
core   +4 more sources

Cellulose nanofiber extraction from unbleached kraft pulp for paper strengthening

Cellulose, 2023
Sufeng Zhang, Zhang Sufeng, Coseri Sergiu   +2 more
exaly   +2 more sources

Production of microfibrillated cellulose from unbleached kraft pulp of Kenaf and Scotch Pine and its effect on the properties of hardwood kraft: microfibrillated cellulose paper

Cellulose, 2013
This work investigated the effect of using Kenaf bast fibre kraft pulps compared to Scotch Pine kraft pulps for producing microfibrillated cellulose (MFC) and its employment for improving mechanical and physical properties of handsheets made from ...
Blademo, A., Afra, Elyas,, Lindström, Tom,, Naderi, A., Rezayati Charani, Pejman Rezayati,, Charani, P. Rezayati, Dehghani-Firouzabadi, Mohammadreza,, Afra, E., Dehghani-Firouzabadi, M., Naderi, Ali,, Blademo, Åsa,   +10 more
exaly   +2 more sources

Effect of refining on strength efficiency in twin-wire roll forming of never-dried unbleached softwood kraft pulp

Nordic Pulp and Paper Research Journal, 2016
Whereas refining is required for the strength development of chemical pulps, it has been unclear how refining affects the utilization of the furnish strength, as reflected by the handsheet strength, in the machine-made paper (strength efficiency).
Bengt Nordstrom
exaly   +2 more sources

Surface characterization of unbleached kraft pulps by means of ESCA

Cellulose, 1994
The effect of digestion conditions (amount of effective alkali, digestion time) on the surface compositions of unbleached softwood (Pinus sylvestris) kraft pulp has been investigated by electron spectroscopy for chemical analysis (ESCA). The quantities monitored were the angular dependence of the total O/C ratio, the relative amounts of carbons in ...
Janne Laine, Per Stenius, Gilbert Carlsson, G�ran Str�m   +3 more
openaire   +1 more source