Method of treating wood or other material for obtaining ligno - cellulose, cellulose - chemical products

摘要

Chips of wood or a lignocellulosic matter of any kind are impregnated by immersion in a solution of alkali metal or alkaline-earth metal salts and/or hydroxides in the presence or absence of small quantities of water-soluble solvents of the glycol, diol or aminoalcohol type, and are then drained. The impregnated wood or lignocellulosic matter is introduced into a metal cylinder or other receptacle. After leakproof closing, the latter is heated solely from the outside to 150-190 DEG C. The cooking takes place in solid phase. After cooking, the liquid product is milled, pressed to extract therefrom a black liquor which can be burnt directly and a cellulose pulp of good quality. The presence of abovementioned solvents improves the whiteness and the quality of the pulp.