METHOD OF PRODUCING CELLULOSE FROM NON-WOOD PLANT MATERIAL WITH NATIVE CELLULOSE CONTENT OF NOT MORE THAN 50% AND METHOD OF PRODUCING CARBOXYMETHYL CELLULOSE THEREFROM Russian patent published in 2012 - IPC C08B11/12 C08B1/00 C08B1/02 

FIELD: chemistry.

SUBSTANCE: invention relates to production of high-molecular weight compounds and is meant to obtain cellulose, used as raw material in chemical industry, as well as in textile, paper, construction and other industries, and for producing carboxymethyl cellulose, used as a mud stabiliser when drilling oil and gas wells, in mining-and-chemical industry, as antiresorbents in synthetic detergents, as well as in other industries. The method of producing cellulose involves using non-wood plant material (silver grass, straw and fruit coats of grain crops) with native cellulose content of not more than 50%. The material is washed with water at 40-70°C and atmospheric pressure for 0.5-4 hours. The material is delignified with aqueous nitric acid solution with concentration 2-8% and treated at temperature 90-95°C for 4-20 hours. The solid phase is separated. The material is treated with aqueous sodium hydroxide solution with concentration 1-4% at temperature 60-95°C for 1-6. The obtained cellulose is filtered, washed with water and its moisture content is reduced. The invention also relates to a method of producing carboxymethyl cellulose. The obtained cellulose is activated with aqueous sodium hydroxide solution at temperature 10-20°C for 20-40 minutes. Further, the sodium salt of monochloroacetic acid is esterified at temperature 10-20°C for 20-40 minutes while stirring and the reaction mass is then held without stirring while maintaining the temperature conditions for 1-3 hours. The reaction mass is then left to mature for 1-2 hours at temperature 60-80°C. Drying is then carried out at temperature 60-80°C.

EFFECT: high technological effectiveness of producing cellulose and carboxymethyl cellulose, high quality of the end product when producing carboxymethyl cellulose by increasing its degree of polymerisation and possibility of using the obtained cellulose as a commercial product.

5 cl, 8 ex