METHOD FOR PRODUCING HIGH-PURITY FLAX FIBRE CELLULOSE Russian patent published in 2015 - IPC C08B1/08 

FIELD: chemistry.

SUBSTANCE: invention refers to the chemical industry and can be used for producing cellulosic raw materials. Flax fibre is successively processed in a sulphuric acid solution and washed at a temperature of 25-30°C for 25-30 minutes; that is followed by oxidative processing in an alkaline solution of hydrogen peroxide containing a stabilising agent, first at a temperature of 20-25°C at a modulus of 0.5-0.6 for 10-15 minutes, then at a modulus of 0.8-0.9 for 10-20 minutes, then at a modulus of 1.0-1.1 for 30-60 minutes at a temperature of 70-75°C; the temperature is then increased to 96-98°C and maintained for 30-60 minutes; the modulus is reduced to 0.1-0.2, and the boiling process is continued for 50-60 minutes. That is followed by the additional oxidative processing in the alkaline solution of hydrogen peroxide in the presence of a silicate stabilising agent at a temperature of 96-98°C for 50-60 minutes followed by washing in water and processing in an aqueous solution of acetic acid.

EFFECT: invention provides producing the high-purity flax fibre with high alpha-cellulose yield, low residual natural impurities, high wetting rate and low degree of polymerisation.

3 cl, 2 tbl