METHOD FOR DELIGNIFICATION OF CELLULOSE MATERIALS Russian patent published in 2022 - IPC D21C9/10 

FIELD: pulp and paper industry.

SUBSTANCE: invention relates to the pulp and paper industry, namely to the methods for delignification of cellulose in the processing of mainly wood. This method can also be used for processing other types of cellulose materials: cake, cotton, flax, hemp, jute, straw, rice husks and others. Delignification of cellulose materials is carried out by sequential treatment with lipase and an oxidizing agent, and the treatment of cellulose materials is carried out with a mixture of one percent solutions of lipase and oxyethylated fatty acid or its derivative at a mass ratio of 1:1÷4 for 0.5-1.5 hours at a temperature of 20-40°C. Penta-oxyethylated tridecanoic acid monoethanolamide ester with the formula C₁₂H₂₅CONHCH₂CH₂O(C₂H₄O)₅H is mainly used as a derivative of oxyethylated higher fatty acid. Lipase is selected from Candida, Aspergillus, Pseudomonas, Humicola, Chromobacter. A delignification cellulose material is obtained at a lower temperature and time of suspension processing and a target product with a reduced lignin content. An increase in the reactivity of cellulose to viscose formation after delignification is also achieved.

EFFECT: method allows for the delignification of cellulose materials, while simultaneously achieving a low degree of environmental impact.

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