METHOD OF OBTAINING CELLULOSE NITRATES Russian patent published in 2015 - IPC C08B5/02 

FIELD: chemistry.

SUBSTANCE: invention relates to field of obtaining highly molecular compounds and is intended for obtaining cellulose nitrates (colloxylins) used in production of ballistite gun powder, solid rocket fuels and industrial explosive substances, in production of celluloid, varnishe, putties, linoleum, detectors of ionising radiation, test-diagnosticums of various diseases, biological indicators, in production of artificial leather and other modern types of production. Method of obtaining cellulose nitrates includes nitration of preliminarily crushed initial cellulose with sulphur-nitrogen mixture, pressing of waste working acid mixture with, replacement of working acid mixture, adsorbed in cellulose nitrates, first, with diluted waste working mixture, then with water to neutral reaction, further filtration, stabilisation of cellulose nitrates with application of 0.01-0.03% soda and water solution, pressing; as initial cellulose used is technical cellulose from miscanthus or fruit shells of cereal crops or straw of oilseed flax varieties preliminarily crushed on sieve with cell size 1 mm, with application of working acid mixture H₂SO₄:HNO₃:H₂O, components of which are in ratio 34-38:48-52:14-16, nitration is carried out for 30-40 minutes with modulus 1:25, with application of waste working acid mixture, diluted to concentration 20-25%, with successive realisation of cooking in water at temperature 90-95°C for 60-90 minutes, pressing, washing with cold water, washing with soda solution at temperature 25-70°C for 5-10 minutes, cooking of cellulose nitrates in the same soda solution for 2,5-3,5 hours at temperature 85-95°C, washing with cold water, pressing, cooking in water for 60-90 minutes at temperature 90-95°C, pressing, washing with cold water, filtration with obtaining cellulose nitrates ready for transportation or drying to required humidity When technical cellulose from miscanthus or fruit envelopes of fruit shells of cereal crops is used as initial cellulose, after first cooking in water, autoclaving in 0,2-0,5% nitric acid solution at temperature 120-130°C and pressure 1,8-2,2 atm is realised with further washing with cold water.

EFFECT: application of invention makes it possible to extend assortment of obtained grades of colloxylins in accordance with existing demand by creation of conditions for optimisation of time, temperature characteristics and applied reagents with simultaneous preservation of weight part of nitrogen in CN, viscosity and CN solubility in alcohol-ether mixture at the prototype level.

2 cl, 4 dwg, 1 tbl, 4 ex