Results 181 to 190 of about 17,855 (226)

Modelling of biomass fractionation by prehydrolysis-delignification

Chemical Engineering Science, 1988
Abstract A two-stage process is investigated as a potential fractionation method for barley straw biomass. Modeling of dilute-acid prehydrolysis shows that hemicellulose saccharification rate is controlled by chemical reaction; in the case of delignification of the prehydrolyzed residue by high-consistency clorination, the rate-controlling step is ...
Gy. Marton, M. Kovacs, V. Oreopoulou, E.G. Koukios   +3 more
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Kinetics of Delignification: A Molecular Approach

Science, 1982
A treelike model has been proposed for the structure of lignin. Kinetics of delignification are formulated to account for the cleavage of linkages along the linear primary chains and at the cross-links. Experimental data obtained from isothermal delignification are used to verify this theory.
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Selective solvent delignification for fermentation enhancement

Biotechnology and Bioengineering, 1983
AbstractCellulose and hemicellulose in renewable biomass resources such as cornstover and wheat straw have been examined as substrates for the production of ethanol. A mixed culture of selected strains of Clostridium thermocellum and Clostridium thermosaccharolyticum are used to accomplish both the hydrolysis and fermentation of these carbohydrates in ...
G C, Avgerinos, D I, Wang
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Xylanase effects on pulp delignification

Chemical Engineering Communications, 2002
Xylanase effects on softwood pulp delignification were investigated experimentally and using mathematical models. The effect of xylanase molecular size on pulp delignification was investigated. As xylanase molecular weight decreased from 67 kDaltons to 20 kDaltons, lignin removal from pulp increased from 30 wt% to 48 wt%, respectively.
David Whitmire, Biswajit Maiti
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The Role of Hemicellulose in the Delignification of Wood

Canadian Journal of Chemistry, 1975
Hemicellulose was selectively removed from white birch by treatment with cold alkali. Untreated and alkali-treated samples were pulped to various stages of delignification by the acid chlorite process. The acid chlorite reagent was shown to be selective for lignin removal from both samples during the first 60% of delignification.In alkali-treated ...
A. J. Kerr, D. A. I. Goring
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THE MECHANISM OF THE ALKALINE DELIGNIFICATION OF WOOD

Canadian Journal of Research, 1941
Measurement was made of the rate of delignification of sprucewood with lithium, barium, sodium, potassium, and tetra-ethyl ammonium hydroxides under closely controlled conditions of temperature and concentration. The reaction rates were compared with the ionic mobilities and adsorption coefficients of the different alkalis.
G. L. Larocque, O. Maass
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Ozonolytic Delignification of Wheat Straw

Russian Journal of Physical Chemistry A, 2020
The dynamics of wheat straw delignification with ozone treatment is studied. The dependence of the residual lignin content on the specific absorption of ozone is determined. It is found that in a prolonged stage of ozonation, ozone is consumed mostly for the reaction with lignin.
E. M. Ben’ko, D. G. Chukhchin, N. A. Mamleeva, A. N. Kharlanov, V. V. Lunin   +4 more
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Delignification of Biomass Using Alkaline Glycerol

Energy Sources, 2005
Ailanthus altissima and Spruce orientalis chips were delignified by using glycerol as a solvent and alkaline-gliycerol with and without catalyst at different temperatures (438, 458, 478, and 498 K) in atmospheric pressure, and results were compared with the other organic solvent systems.
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On the role of carbohydrates in oxygen delignification

Nordic Pulp & Paper Research Journal, 2005
The long-term trend regarding wood is an increase in price. Because wood contributes to a large part of production costs, the efficient utilisation of wood is greatly desired to reduce production costs for kraft pulp producers. During the 1990s, the development of improved modified kraft cooking began, which led to higher yields. There was also a trend
Helena Wedin, Mikael E. Lindström, Martin Ragnar   +2 more
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Biological Delignification Of Biomass

2016
The annual production of lignocellulosic matters has been estimated about, 1010 metric tons worldwide [2]. The main constituents of the lignocellulosic biomass are cellulose (a homopolymer of glucose), hemicellulose (a heteropolymer of pentoses and hexoses) and lignin (a polymer of phenyl propanoid units) [82].
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