The method of microcrystalline cellulose
(57) Abstract:The invention relates to the modification of cellulose, in particular to a method for producing microcrystalline cellulose(MCC),which finds application in food, pharmaceutical, cosmetic, porcelain, ceramic industry. Microcrystalline cellulose is obtained by processing fibrous waste cotton and textile industry when heated to 80oC for 1 h with a mixture of 3.5% hcl and 0.6% nitric acid in the presence of catalyst (10% phosphorus molybdenum acid at the liquid module 1:10, followed by rinsing and drying. The invention allows to simplify the technology of the ICC and to obtain a homogeneous molecular mass of cells with high yield and degree of polymerization 130-190. table 1. The invention relates to the modification of cellulose, in particular to a method for producing microcrystalline cellulose (MCC), which finds application in food, pharmaceutical, cosmetic, porcelain, ceramic industry.A method of obtaining MCC, using hydrochloric acid solutions with application-low-tech gaseous reactants (e.g., peroxide x is 1/00, 1987).Closest to the invention is a method for MCC - ed. St. USSR N 1812179 A, class C 08 B 1/00, 1990, where the oxidant using gaseous ozone.In this way a good degree of polymerization are associated with lower output ICC and harmful emissions into the atmosphere.The technical result of the present invention is to simplify the process of obtaining ICC, uniform molecular weight, increasing the degree of homogeneity in the degree of polymerization (SP < 200), which is set to improve reactivity and physico-chemical properties.The invention is illustrated by examples. For all examples are taken lint with the following parameters: the average fiber length is 7-8 mm, litter - 4,5%, ash content of 1.7% content-cellulose 96%.Example 1
Lint treated with 100 ml of a mixture of 3-acids of 3.5% hydrochloric acid, and 0.6% nitric acid, 10-3% phosphorus molybdenum acid at a temperature of 80oC for 1 h, the processing module 1:10. The obtained MCC filtered and washed with a neutralizing solution of concentrated soda and water, then treated with absolute ethanol or butanol and dried.The output ICC - 88%, average degree of polymerise the method presented in the table.The product obtained in 1 and 4-6 examples, has the best performance according to the degree of polymerization and the output of the LCC. The absence in the reaction mixture of nitric acid or phosphorus-molybdenum acid (example 2, 3) leads to a fall in output ICC and reduce the homogeneity of the resulting product.Example 7 shows that increasing the concentration of phosphorus molybdenum acid two orders of magnitude leads to a deterioration of parameters of the process of obtaining MCC, i.e., the best performance is achieved at low concentrations of phosphorus molybdenum acid in solution.The invention allows to obtain more uniform molecular weight MCC, with a higher yield and degree of polymerization 130-190, to simplify the technology of its receipt. The method of microcrystalline cellulose by treatment of cellulosic material, which is used as the fibrous waste cotton and textile industry, with a mixture of hydrochloric acid and an oxidizing agent when heated to 80oC for 1 h followed by washing and drying, characterized in that the mixture used in 3.5% hydrochloric acid with an oxidant to 0.6% nitric acid, and the treatment is carried out in prisutstvie the
FIELD: production of microcrystalline cellulose useful in food processing industry, cosmetic industry and paint-vehicle industry.
SUBSTANCE: cellulose-containing material of determined humidity is treated with mixture of hydrogen chloride with air in ratio of 1:(2-10) at temperature of 25-70°C. Gaseous hydrogen chloride is cooled before mixing with air, and gas-air mixture temperature is adjusted by air heating before mixing with hydrogen chloride.
EFFECT: microcrystalline cellulose of maximal polymerization ratio; decreased amount of non-target fractions and debris.
5 cl, 1 dwg, 5 ex
FIELD: cellulose and cellulose derivatives.
SUBSTANCE: invention relates to powdered cellulose characterized by average degree of polymerization 150-450, average particle diameter 30-250 μm, apparent specific volume exceeding 7 cm3/g, and retention capacity regarding polyethylene glycol with molecular mass 400 at a level of 190% or higher. Group of inventions also comprises method of preparing powdered cellulose and composition for a molded product.
EFFECT: enlarged assortment of cellulose materials.
3 cl, 4 tbl, 28 ex
FIELD: paper-and-pulp industry.
SUBSTANCE: invention relates to manufacture of cellulose derivatives, in particular to a process of manufacturing microcrystalline cellulose, which can be used as filler in chemical-and-pharmaceutical industry, food processing industry, and as sorbent and filter material in technical areas, and as starting material for manufacture of low-viscosity cellulose derivatives. Pulp having whiteness up to 65% is subjected to two-step processing: hydrolysis of raw material in sulfuric acid and subsequent bleaching of hydrolyzed material with chlorine dioxide.
EFFECT: expanded technological possibilities.
FIELD: chemical processing of cereal crop straw into fine-grain cellulose used in pharmaceutical, food-processing, perfume and chemical branches of industry.
SUBSTANCE: method involves combining processes of delignification and hydrolysis of ground wheat straw by processing basic material with solution containing mixture of acetic acid and hydrogen peroxide at molar ratio of 0.2-0.6 in the presence of sulfuric acid catalyst used in an amount of 1-3% by weight of totally dry straw with duty of water of from 5 to 10, temperature of 110-140 C during 2-4 hours; processing resultant fibrous product with mixture of acetic acid and hydrogen peroxide with molar ratio of 0.1-0.3, at temperature of 100-120 C, duty of water of from 5 to less than 10 during 1-3 hours.
EFFECT: increased efficiency and improved quality of fine-grain product.
1 tbl, 8 ex
SUBSTANCE: to reduce non-bound glyoxal content cellulose ethers processed by glyoxal are processed by water solution of one or more water-soluble aluminium salts or one or more water-soluble borates, or combination of one or more water-soluble aluminium salts and one or more water-soluble borates, and, if adjustment of pH factor is required, with relevant buffer substances added, and is dried. Invention also claims method of non-bound glyoxal content reduction in cellulose ethers processed by glyoxal by mixing cellulose ether at temperature between 20°C and 70°C with water solution of one or more water-soluble aluminium salts or one or more water-soluble borates, or combination of one or more water-soluble aluminium salts and one or more water-soluble borates. For pH factor adjustment, the solution can also include buffer substances, and is further dried.
EFFECT: reduced non-bound glyoxal content in ethers of cellulose processed by glyoxal.
9 cl, 6 ex
FIELD: textile, paper.
SUBSTANCE: method relates to production of microcrystalline cellulose (MCC), which is widely used in pharmaceutical, food and perfume industries. Used as stabiliser of water-latex paints and emulsions and as sorbent for chromatography. In medicine MCC is used as biologically active supplement and stabiliser of medical agents. Method for production of microcrystalline cellulose includes autohydrolysis of ground wood material. Autohydrolysis is carried out by water steam at 180-240°C for 2-3 min. Autohydrolised wood is treated with boiling water. Then with solution that contains CH3COOH, H2O2, H2SO4, at the temperature of 100-110°C for 2.5-3 hours.
EFFECT: increased efficiency of method.
12 ex, 1 tbl, 1 dwg
FIELD: textile, paper.
SUBSTANCE: present invention relates to ground fibres of unbleached cotton lint in the form of loose mass. Loose mass has specific weight of at least 8 g/100 ml. At least 50% of loose mass fibres pass through standard USA sieve with calibre No.10 (2-millimetre hole). Ground fibres of unbleached cotton lint are produced by preparation of loose mass from unbleached cotton lint of the first cut, second cut, third cut, or unbleached cotton lint, or their mixtures. Then loose mass of unbleached cotton lint is ground down to size, when at least 50% pass through standard USA sieve of calibre No. 10 (2-millimetre hole). Produced ground fibres of unbleached cotton lint in the form of loose mass are used to produce ether derivatives of cellulose.
EFFECT: method makes it possible to reduce energy inputs in production of ether derivative at the stage of cellulose mixture activation reaction with at least one etherifying agent down to at least 15%.
3 cl, 34 ex, 4 tbl
SUBSTANCE: invention involves fractionating plant material, steaming the fraction, acid hydrolysis, first and second alkaline hydrolysis and bleaching.
EFFECT: process is characterised by favourable conditions for processing material while maintaining structural homogeneity of the end substance, does not require high power consumption and other production expenses.
SUBSTANCE: method includes vegetable material fractionation, fraction autoclave treatment with three times washing-off, the first acid hydrolysis with three times washing-off, alkaline hydrolysis with three times washing-off, the second acid hydrolysis with three times washing-off, the first bleaching with three times washing-off; the second bleaching with four times washing-off. Additional homogenisation stage is possible.
EFFECT: according to invention the method does not require the use of expensive equipment, does not propose the use of high-toxic reagents, includes not complicated process operations, differs by the production volume.
SUBSTANCE: invention relates to the production of carboxylated fibre. The method includes catalytic carboxylation of cellulose fibres in at least two stages of catalytic carboxylation, located successively, in which the primary catalyst, the secondary oxidating agent, and, if necessary, an agent for pH regulation are added in the beginning of each stage.
EFFECT: invention makes it possible to increase a level of carboxylation with effective expenditures.
11 cl, 1 dwg, 8 tbl, 5 ex