Method for producing paper pulp, lignins, sugars and acetic acid by frantionation of lignocellulosic vegetable material in formic/acetic acid medium
AssigneeCompagnie Industrielle de la Matiere Vegetale
InventorsGérard Avignon, Michel Delmas
Life of this patent
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Abstract
A method for producing paper pulp from a lignocellulosie vegetable raw material. The method includes contacting the raw material with a mixture of formic acid and acetic acid (in an amount more than 5 wt. % of the mixture) at a temperature and for a suitable reaction time, the whole being performed at room temperature. The paper pulp is separated from the organic phase and optionally bleached with ozone. The organic phase is treated to enable the recycling of the formic and acetic acids and the extraction of lignins, sugars and excess acetic acid.
Claims17
Process for producing paper pulp, lignins, sugars and acetic acid, from a lignocellulosic plant material, which comprises the following successive steps:
- (i) impregnating the lignocellulosic plant material at atmospheric pressure and at a first temperature, higher than 50° C., by immersion with a mixture of formic acid containing at least 5% of acetic acid by weight, so as to obtain a suspension;
- (ii) subjecting the suspension to a fractionation reaction at a reaction temperature of between 50° C. and 115° C.;
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- (iii) separating at atmospheric pressure and at said reaction temperature a solid fraction constituting paper pulp from an organic phase containing in solution the starting formic acid and acetic acid, solubilized monomeric and polymeric sugars, lignins and acetic acid derived from the plant material.
Dependencies are inferred from the claim text.