Delignification

delignification

[dē‚lig·nə·fə′kā·shən]
(chemical engineering)
A chemical process for removing lignin from wood.

Delignification

 

destruction of the lignin that fills the intermycelial spaces in the walls of plant cells. Delignification occurs in a dead cell through the activity of enzymes secreted by neighboring living cells or parasitic fungi that cause, for example, white rot of woody plants. In the stalks of herbaceous plants, the process precedes obliteration and destruction of the internal elements of the protoxylem. Delignification and subsequent thinning of the sclereid walls accompany the maturation of pears and quinces. Delignification is used in industry to obtain cellulose; the lignin is removed from the cell walls by boiling wood at high pressure with caustic soda or calcium bisulfite. Delignification may also be caused by the action of Schultze powder (nitric acid with Berthollet salt) on the cell walls.

References in periodicals archive ?
The increased measurement frequency fulfills all pulping process control needs and safely provides the genuine pulp Kappa number in dedicated process stage applications from unbleached brown stock pulp to oxygen delignification," says Risto Rinne, Fiberline Analyzer Business Manager, Valmet.
The application of organosolv delignification in chemical pulping has received the most attention.
Alkali and enzymatic delignification of sugarcane bagasse to expose cellulose polymers for saccharification and bio-ethanol production.
Study of delignification of Eucalyptus urophylla hybrid by the kraft process for production of cellulose.
In order to break down the lignocellulosic bonds and to increase bioavailability of nutrients, various physical and chemical delignification methods have been examined in agricultural co-products such as rice and wheat straw [3].
Furthermore, large variety of potential substrates has raised interest in the use of laccases in several industrial applications, such as pulp delignification, textile dye bleaching, effluent detoxification, biopolymer modification and bioremediation [11,12] (Gianfreda et al, 1999; Xu, 1999).
For instance, ALMEIDA (2003) stated, that the extractive and lignin content of the wood had a direct influence on the alkali consumption, yield and delignification rate, enabling the determination of the potential of a raw material for cellulose pulp production.
In conjunction with the expansion, Fibria plant requires another 160 tons per day of oxygen, for use in the pulp delignification stage, also known as pre-bleaching pulp.
ABSTRACT: The present study was conducted to analyze the effect of three different organic solvents (Ethanol, Methanol and Acetone) on delignification of rice husk (basmati rice).
The new patent covers a system and method for oxygen-assisted delignification of lignocellulosic biomaterials and lignin recovery, which further improves the quality of the pulp produced by the AST Organosolv pulping process.