METHOD OF PRODUCING CELLULOSE Russian patent published in 2025 - IPC D21C3/02 D21C1/06 

FIELD: production of cellulose.

SUBSTANCE: invention relates to pulp and paper production and can be used for production of cellulose and cellulose-based products from vegetal raw materials. Method of producing cellulose involves purifying cellulose-containing fibre, cooking in an alkaline solution containing a surfactant, bleaching in a hydrogen peroxide solution, intermediate washing and drying. Cellulose-containing fibre used is hemp fibre with length of 5-40 mm. Cooking in alkaline solution is carried out with addition of sodium sulphide. Purification of cellulose-containing fibre is carried out first in solution containing 0.3 wt.% surfactant triethanolamine, at temperature 40 °C for 45 minutes, and then in solution containing 3.0 wt.% sodium hydroxide, 0.3 wt.% triethanolamine surfactant, at temperature of 85 °C for 60 minutes. Cooking in an alkaline solution is carried out with addition of sodium thiosulphate at temperature of 100 °C for 180 minutes at the following content of components in the solution, wt.%: sodium hydroxide – 3.0, triethanolamine – 0.07, sodium sulphide – 0.4-0.6, sodium thiosulphate – 0.5-0.7.

EFFECT: invention makes it possible to reduce duration of cellulose production by 1.5 times on average and increase cellulose yield by 4-11%.

1 cl, 2 tbl, 4 ex