The method of microcrystalline cellulose
(57) Abstract:The method concerns of microcrystalline cellulose from straw herbaceous plants of the family of grasses that can be used in chemical, cosmetics, pharmaceutical, food industries and medicine. Of air-dried plant materials produce pulp of Kurshner by well-known methods or subjected to delignification in alkaline solution. Then the pulp is subjected to acid hydrolysis. The method allows to obtain microcrystalline cellulose, containing no admixture of aromatic character in the form of lignin. 3 table. The invention relates to the manufacture of cellulose derivatives, namely to obtain microcrystalline cellulose (MCC), which can be used in chemical, cosmetics, pharmaceutical, food industries and medicine.A method of obtaining ICC (RF patent 2147057), chosen for the prototype, a pre-hydrolysis subjected to mechanical grinding to a powder air-dried oat straw in sulfuric and proximodorsal acids. MCC has the following indicators: degree of polymerization (SP) 87-210 the C lignin Komarova, that, depending on the purpose for use, MCC, is not always desirable indicator.The present invention is to obtain ICC straw herbaceous plants of the family cereal that does not contain impurities of aromatic character in the form of lignin.This is a technical result.Straw of cereals refers to the waste of agricultural production. In Russia annually collects more than 200 million tons of straw. From the straw of cereals can produce two types of fibrous semi-finished products: coarse straw mass (yield about 70% of raw material) for use in the production of cardboard and paper for corrugation and pulp (yield from raw materials 35-45%), which is unbleached and white-washed the form can be used for the production of quality paper and cardboard. For industrial processing, it is preferable to use the straw of wheat and rye, which are more durable pulp, paper and cardboard, than other types of straw (C. E. Moskaleva and other Diagnostic signs of non-timber plant and chemical fibers. M : the Forest industry here, 1981. - S. 46). There is information about the use of straw as the Russian is their use as a coarse low-value food (the degree of digestibility of biomass straw does not exceed 15-20%) and bedding material. However, according to our data, the component composition of the biomass straw herbaceous plants of the family cereal similar plant tissue of coniferous and deciduous wood - the main components are cellulose and lignin (table 1). High cellulose content, comparable with the content of cellulose in wood (40-50%), shows the principal possibility of using straw herbaceous plants of the family of cereals as a raw material source for MCC production. The elemental composition of drugs dioxane lignin isolated from straw are presented in table 2. Functional composition of dioxane lignin preparations are presented in table 3.It should be noted that the straw of cereals contains almost no resins, i.e. has a clean environment, is an affordable, renewable raw materials.Xylem herbaceous plants much easier may be subject to physical and chemical processing than wood of coniferous and deciduous species. This can be explained by the following reasons. Wood of coniferous species has a relatively simple structure, so as to 90-95% consists of tracheids are long, thin cells with a flat or spindle-shaped closed ends of the mechanical tissue consists of fibers libriform and fiber tracheids. The main anatomical elements herbaceous plants are fiber, then the vascular, parenchymal, and epithelial cells. The xylem density is determined by the number and diameter of vessels, number parenchyma cells, as well as the wall thickness of the fibers libriform or tracheids. Due to the anatomical structure of the xylem, the greater the density of its forming cells and less significativamente, herbaceous plants are easily amenable to physical and chemical influences.The main components of plant tissue are the polysaccharides (cellulose and lignin. The rest are mecellose polysaccharides, ash components and extractives. Pulp of wood and other plant materials is a linear homopolysaccharide built from elementary units-D-glucopyranose. As in the cell wall lignin is not simply deposited between polysaccharides and is in close Association and forms a so-called lignin-carbohydrate complex, then to explain the mechanisms of chemical transformation of plant tissue are essential differences in the chemical structure of the lignin of wood and herbaceous plants. Lignin softwood tree units vallromanas, siegerrebe and n-coumaric. Softwood and hardwood lignins are characterized by a high degree of kondensirovannoi. For lignin herbaceous plants characterized by a high content of n-Kumarovich units and the large number of easy-hydrolyzed in acidic and alkaline environment of ester groups.Thus, features of the anatomical and chemical structure of herbaceous plants explain them easier physico-chemical processing compared to wood. Note the similarity of the chemical composition of the straw of various herbaceous plants of the family graminaceae, and show the same approach to the processing of these raw sources.The essential features of the invention: method of microcrystalline cellulose from straw herbaceous plants of the family of cereals containing cellulose 40-50%, lignin 18-23%, mecellose polysaccharides, ash components and extractives - the rest, by acid hydrolysis of air-dried plant materials, while before hydrolysis pre-allocate the pulp of Kurshner by well-known methods or subjected feedstock delignification saloon what about the dry straw of herbaceous plants in the family cereal is subjected to mechanical grinding in a vibrating mill to a powder. Then, to obtain the ICC used two approaches: 1) extraction from milled feedstock cellulose as individual substances with subsequent hydrolysis; 2) delignification milled feedstock and subsequent hydrolysis. The first option of receiving MCC associated with the separation of cellulose from plant tissue by the method of Kurshner (A. C. Obolenskaya and other Laboratory work on chemistry of wood and cellulose. M. : Ecology, 1991) and subsequent hydrolysis of cellulose to limit the degree of polymerization proximodorsal acid (PMS) and the classical way. PMS is formed during the reaction with sulfuric acid (H2SO4and hydrogen peroxide H2ABOUT2. This method of obtaining MCC has worked well from an environmental point of view, and, in addition, PMS causes oxidation of residual lignin and has a cellulose destructible action (V. A. Demin, L. S. Kocheva, A. P. Karmanov. Srtucture and properties of microcristalline cellulose received by different methods //Fifth European Workshop on Lignocellulosics and Pulp. Proceedings. Portugal, 1998. - P. 157-159. ). The classical way of obtaining MCC is considered to be the hydrolysis of 2.5 N. hydrochloric acid HCl at 105oC for 2 hours.The second option for the ICC is that the original straw after grinding on vibration is x raw water is used to obtain the ICC by treating PMS and classic way.The use of these two approaches to processing the original plant materials allows to obtain not contain lignin Komarova MCC, because in the first case, the hydrolysis is subjected to the preparation of the pulp, and in the second case, the product from which previously removed lignin. Lignin Komarov was determined by standard method (A. C. Obolenskaya and other Laboratory work on chemistry of wood and cellulose. M. : Ecology, 1991).As the characteristics of the samples obtained MCC used the degree of polymerization (SP). JV samples was determined by the viscosity of their solutions in catocene [Cd(en)3] (OH)3the method error is 1-2% (HP Bolotnikov and other Method of determining the viscosity and degree of polymerization of cellulose // Russian journal of applied chemistry, 1966. - So 39. Vol. 1. - S. 176-180). As an example, annual herbaceous plants of the family cereal examined oats, as an example of perennial herbaceous plants of the family cereal considered meadow fescue.Example 1. Pulp of Kurshner get from the ground to a powder, straw oat in accordance with the following method. A portion of the air-dry straw weight of about 1 g is placed in a conical flask with a capacity of 250 cm3and the nitric acid (density 1.4 g/cm3) and four volumes of 95% ethanol. To the flask and attach the reflux condenser and boil the straw with the mixture on a water bath for 1 hour This treatment is carried out three or four times. After the last treatment, the pulp is sucked dried to constant weight glass Frit, applying suction, washed with 10 cm3fresh nitrogen-alcohol mixture, and then hot water. The filter pulp dried in a drying Cabinet at a temperature of (1032)oC to constant weight. Thus obtained air-dry cellulose of Kurshner transferred into a flask and pour a solution containing PMS. After mixing the components with stirring suspension of straw oats concentration equivalent to 10% of sulfuric acid and 1% hydrogen peroxide (equivalent to 3% of PMS). The water ratio of 1: 50. Flask with reflux condenser heated to the boiling point of the mixture and incubated for 120 min, then removed from the heater, cooled to room temperature and vortex separating the hydrolysate. The resulting ICC washed with water until neutral wash water, and dried. Indicators: lignin Komarova: no; SP: original oat straw - catocene not dissolving pulp of Kurshner of straw oat - 766; M is ovat suspension and handle, as in example 1. Indicators: lignin Komarova: no; SP: original straw of meadow fescue in catocene not dissolving pulp of Kurshner of straw meadow fescue - 1184; MKC-326.Example 3. A portion of air-dried pulp of Kurshner obtained from milled to a powder, straw, oats, transferred into a flask and pour a solution of 2.5 N. HCl. The water ratio of 1: 50. Further treatment is carried out as in example 1. Indicators: lignin Komarova: no; SP 422.Example 4. As a source of raw materials use air-dry straw of meadow fescue. Preparing a suspension and are processed as in example 3. Indicators: lignin Komarova: no; SP 636.Example 5. A portion of the air-dry straw of oats, ground to a powder, transferred into a flask and pour a solution of 2 N. NaOH. The water ratio 1: 5. Flask with reflux condenser heated to the boiling point of the mixture and incubated for 120 min, then removed from the heater, cooled to room temperature and vortex separating the hydrolysate. The resulting product is washed with water until neutral wash water, dried to air-dry state. Further treatment is carried out as in example 1. Indicators: lignin Komarova: who are the product of alkaline delignification, as in example 5. Further treatment is carried out as in example 3. Indicators: lignin Komarova: no; SP 384.Evidence suggests that the straw herbaceous plants of the family cereal serves as a raw material source for the production of MCC. Ecological purity of raw materials and final products can be recommended MCC straw herbaceous plants of the family of grasses for use not only in the chemical industry, but also in medicine, pharmacy, perfumery and food production. The method of microcrystalline cellulose from straw herbaceous plants of the family of cereals containing cellulose 40-50%, lignin 18-23%, mecellose polysaccharides, ash components and extractives - the rest, by acid hydrolysis of air-dried plant material, characterized in that before hydrolysis pre-allocate the pulp of Kurshner by well-known methods or subjected feedstock delignification alkaline solution Paon.
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