Results 111 to 120 of about 284 (165)

Residual Lignin in Unbleached Kraft Pulp. Part 2. -Analysis of Unbleached Kraft Pulp by New Permethylation Method-

Journal of Wood Chemistry and Technology, 1987
Abstract Unbleached kraft pulp (UKP), its residue after extraction with concentrated alkali (α-UKP), bleached kraft pulp prepared from UKP (BKP) and its residue after extraction with concentrated alkali (α-BKP) were permethylated with powdered NaOH and CH3I in their SO2-diethylamine (DEA)-dimethylsufoxide (DMSO) solutions.
Akira Isogai, Atsushi Ishizu, Junzo Nakano   +2 more
openaire   +1 more source

Xylanase-Resistant Xylan In Unbleached Kraft Pulp

Journal of Wood Chemistry and Technology, 1996
ABSTRACT A water-soluble chromophoric xylanase-resitant xylan fraction (LF-D) was separated from a hardwood unbleached kraft pulp (UKP) after hydrolysis with a cellulase/ xylanase-membrane bioreactor. LF-D contained over 70% unremovable inorganic atoms including Si, Na, and S, together with a β-1,4- linked xylan.
Takashi Watanabe, Keigo Mikame, Yoichi Honda, Masaaki Kuwahara   +3 more
openaire   +1 more source

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

Variation of Phenolic Hydroxyl Contents in Unbleached Kraft Pulps

hfsg, 1995
The content of phenolic hydroxyl groups in the unbleached kraft pulp residual lignin was determined in situ by periodate oxidation method. This functional group has been shown to increase steadily with the extent of kraft delignification throughout the entire pulping process.
Yuan-Zong Lai, Sung-Phil Mun, Su-ge Luo, Hsin-Tai Chen, Mohammed Ghazy, Hui Xu, Jian Er Jiang   +6 more
openaire   +1 more source

Study on Alkali-Accessible Chromophores from Unbleached Kraft Pulp

Holzforschung, 2001
Summary An approach to a chromophore composition study using the direct size-exclusion chromatography (SEC-UV) analysis of an alkaline extract of pulp fibre walls is described. Absorbance in the 290–405 nm range of 2% and 18% NaOH extract from unbleached pulps obtained by conventional and extended kraft delignification of black alder wood ...
T. Bikova, V. Klevinska, T. Eremeeva, A. Treimanis   +3 more
openaire   +1 more source

Determination of fiber charge components of Lo-Solids unbleached kraft pulps

Journal of Colloid and Interface Science, 2004
Four different titration methods for measurement of fiber charge were used in this study. Each method gave different fiber charge values depending on the acidity of the end point and the interaction between the fiber chemical components and the titrant.
Nishi K, Bhardwaj, Tuan D, Duong, Viet, Hoang, Kien L, Nguyen   +3 more
openaire   +2 more sources

Partial delignification of unbleached kraft pulp with ligninolytic fungi

Biotechnology Letters, 1979
Unbleached kraft pulp is partially delignified on incubation under specified conditions with ligninolytic fungi, thereby decreasing requirements for bleaching chemicals. Studies withPhanerochaete chrysosporium demonstrated important effects of nutrient nitrogen and molecular oxygen concentrations. Possible approaches to rate enhancement are suggested.
T. Kent Kirk, H. H. Yang
openaire   +1 more source

Surface Characterization of Unbleached Kraft Pulps by Enzymatic Peeling and ESCA

hfsg, 1996
Specific enzymes hydrolyzing pulp carbohydrates can be used for characterization of pulp fibres. By combining enzymatic peeling of fibre hemicelluloses with novel techniques of surface analysis, such as ESCA, new information can be obtained on the location of different components, i.e. xylan, glucomannan and lignin on the fibre surfaces.
Carlsson, Göran, Viikari, Liisa, Ström, Gunnar, Buchert, Johanna   +4 more
openaire   +2 more sources

UASB performance for bleached and unbleached kraft pulp synthetic wastewater treatment

Chemosphere, 2005
This paper presents the performance of two bench scale Upflow Anaerobic Sludge Blanket reactors (UASB) used for the treatment of synthetic substrates that simulate bleached and unbleached cellulose pulp plant wastewaters. The control reactor was fed with diluted black liquor and the treatment reactor with the same substrate plus a mixture of ...
A P, Buzzini, E P, Gianotti, E C, Pires
openaire   +2 more sources

Wet strength improvement of unbleached kraft pulp through laccase catalyzed oxidation

Enzyme and Microbial Technology, 2001
Previous investigations have shown that laccase catalyzed oxidation of lignin containing wood fibers can enhance the strength of medium density fiberboards. In the present work it was investigated if laccase treatment had any impact on the tensile strength of a high yield unbleached kraft pulp. Treatment with laccase alone had only a very little effect
Lund, M., Felby, C.
openaire   +2 more sources