METHOD OF CONTINUOUS HYDROLYSIS FOR THE PRODUCTION OF MICROCRYSTALLINE CELLULOSE Russian patent published in 2018 - IPC C08B15/02 

FIELD: technological processes.

SUBSTANCE: invention relates to the pharmaceutical, food and other industries and can be used to produce microcrystalline cellulose (MCC). Continuous hydrolysis process for the production of microcrystalline cellulose comprises treating the cellulose-containing material with a gas-air mixture of hydrogen chloride with air, wherein a tubular reactor is used to carry out the process, in which pre-comminuted wood pulp is continuously fed, the cellulose is moved along the axis of the reactor providing the residence time of the cellulose in the reactor for 15–60 minutes, perform countercurrent cellulose supply of hydrogen chloride in an amount of 3–7 % of the weight of dry cellulose and air at a temperature of 20–50 °C in an amount that provides a concentration of hydrogen chloride in a gas-air mixture of 10–50 vol.%, discharge the hydrolyzed cellulose and bleach it with a solution of sodium hypochlorite at a rate of 2–6 g per 1 kg of cellulose (according to the active chlorine). For continuous hydrolysis, sulphite or sulphate bleached cellulose is used from coniferous or hardwood raw material, ground to a particle size of not more than 50×50×6 mm, with a moisture content of 5–20 %. Bleaching of the obtained microcrystalline cellulose is carried out at pH 2–4 for 1–3 hours at a ratio of cellulose: sodium hypochlorite solution 1:(8–12).

EFFECT: high performance of the process through the implementation of a continuous process is provided; high quality product with a whiteness of more than 85 % is obtained.

3 cl, 4 ex