Method of cellulose producing for ethers and esters

FIELD: pulp and paper industry.

SUBSTANCE: invention relates to production of cellulose for cellulose ethers and esters and can be used in pulp and paper industry. Method involves cellulose-containing raw material acid cooking in boiling device with bisulfite solution on sodium base in presence of deresinator and boiling product hot refinement with sodium hydroxide in presence of additive. Boiling product hot refinement is carried out in stages, hot refining first stage is performed in presence of complexing agent in amount of 0.1–0.2 % in terms of absolutely dry fiber mass, second stage is performed with separation of spent solution, which is supplied to refining first stage in amount of 20–30 % of total sodium hydroxide consumption at first stage, and boiling product hydrothermal processing is performed between first and second refining stages at temperature of 60–70°C for 50–60 minutes.

EFFECT: as a result obtained cellulose has following properties: high content of alpha-cellulose, higher viscosity and low content of lignin.

4 cl, 1 tbl, 4 ex

 



 

Same patents:

FIELD: chemistry.

SUBSTANCE: invention relates to a method of reducing resinous contaminants in an aquatic medium, formed during paper production or pulping, the method including the following steps: a) obtaining an aquatic medium containing resinous contaminants, obtained during paper production or pulping; b) preparing fine calcium carbonate and/or precipitated calcium carbonate; c) preparing a hydrophobisation agent; d) contacting the fine calcium carbonate and/or precipitated calcium carbonate from step (b) with the hydrophobisation agent from step (c) to obtain hydrophobisated fine calcium carbonate and/or hydrophobisated precipitated calcium carbonate; and e) contacting the aquatic medium from step (a) with the hydrophobisated fine calcium carbonate and/or hydrophobisated precipitated calcium carbonate from step (d); to the use of the hydrophobisated fine calcium carbonate and/or hydrophobisated precipitated calcium carbonate to reduce the amount of resinous contaminants in the aquatic medium, as well as to hydrophobisated fine calcium carbonate and/or hydrophobisated precipitated calcium carbonate and a composite of hydrophobisated fine calcium carbonate and/or hydrophobisated precipitated calcium carbonate and resinous contaminants.

EFFECT: improved properties.

28 cl, 10 dwg, 5 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to field of chemical processes for processing cellulose fibres, in particular wood mass. Method of composition obtaining includes the following stages: 1) addition of alkali earth metal oxide or alkali earth metal hydroxide and silicon oxide compound, selected from group, consisting of colloidal silicon oxide and silicate, as well as their combinations, into aqueous medium with obtaining aqueous mixture in such a way that silicon oxide compound and alkali earth metal oxide or alkali earth metal hydroxide together form main part of composition material which is not solvent; and 2) keeping said aqueous mixture for at least 1 hour. Invention also relates to composition, obtained by thereof, to application of said composition, to method of obtaining processing mixture, to method of obtaining paper products and to paper product.

EFFECT: ensuring increased degree of whiteness of wood fibres, increased circulation of technological water, reduction of fibre loss in bleaching.

22 cl, 1 tbl, 8 ex

FIELD: chemistry.

SUBSTANCE: invention describes a composition and methods of removing resin from wood chips used in sulphate pulping.

EFFECT: method is particularly suitable for removing triterpene and triterpenoid resin.

13 cl

FIELD: textile, paper.

SUBSTANCE: method to produce cellulose for sanitary-hygiene types of paper is realised by means of wood chips boiling with a sulfite solution in presence of a mixture of anion, non-ionogenic and amphoterous surfactants, and also a salt or salts from a group including phosphates and carbonates of sodium, disilicate and sodium sulfate. Mixture consumption is 0.3-1.5 kg per 1 t of absolutely dry chips.

EFFECT: reduction of resin and oil content in cellulose, level of contamination of paper machine elements with resin particles, higher mechanical strength of cellulose at its lower stiffness, increased absorption ability.

1 tbl

Control of deposits // 2471031

FIELD: textiles, paper.

SUBSTANCE: agent for prevention the formation of deposits in a paper-making machine comprising a first component comprising at least water-soluble sulfonated polymer and a second component comprising at least hypochlorite. The invention also relates to a method of preventing deposits in the paper production system using the said agent. After receiving information about the composition of deposits formed in the paper production system, the deposit control agent can be used, which is designed for effective prevention the formation of similar deposits.

EFFECT: more effective use of deposit control agents.

20 cl, 2 ex

FIELD: chemistry.

SUBSTANCE: natural calcium carbonate with an activated surface or an aqueous suspension containing natural calcium carbonate with an activated surface with pH higher than 6.0, measured at 20°C, is added to the medium. The natural calcium carbonate with an activated surface is a product of reaction of natural calcium carbonate with carbon dioxide and one or more acids.

EFFECT: improved removal of resin from aqueous medium.

25 cl, 5 dwg, 1 tbl

FIELD: textile fabrics, paper.

SUBSTANCE: method is related to suppression of resin and sticky materials deposits creation in fiber mass in process of paper production and may be used in pulp and paper industry. Method includes stage of multi-stitched cation-active polymer addition into paper liquid mass prior to formation of paper web. This polymer is produced in compliance with the method comprising the following stages: (1) polymerisation of monomer components by free radical initiation with preparation of main cation-active polymer solution, in which at least one of monomer components represents cation-active monomer component such as diallyl dialkyl ammonium monomer; and (11) contact of main cation-active polymer solution with additional initiator of free radical polymerisation with provision of mutually binding connections between main cation-active polymers with provision of multi-stitched cation-active polymer, where this multi-stitched cation-active polymer has higher molecular mass compared to main cation-active polymer.

EFFECT: elimination of anion garbage by fixation of colloidal particles in fiber and suppression of deposits creation by resin and sticky materials.

20 cl, 11 tbl, 13 ex

The invention relates to a method for production of cellulose and can be used in the pulp and paper industry in the manufacture of sulphite pulp with a lower content of resins and fats

The invention relates to the technology of pulp and can be used in the pulp and paper industry in the manufacture of sulfite pulp for paper, cardboard and chemical processing
The invention relates to technology for processing trudnorazreshimoj paper, mainly paper-based old money paper money, and, in particular, to methods of preparation of pulp from waste paper to grind for the manufacture of paper and cardboard

FIELD: textiles, paper.

SUBSTANCE: present invention relates to a method of manufacturing paper or cardboard, the aqueous composition used in the manufacture of paper and cardboard. The claimed object is solved in that the paper or cardboard mass is diluted with an aqueous composition obtained from particles of colloidal size of carbonate and bicarbonate and other forms of carbonate in aqueous solution, so that the pH value in the aqueous solution is substantially maintained at a level of 6.0-8.3 during formation, and water is removed from the mass by means of draining, pressing and drying. The invention also relates to a method of preparing an aqueous composition used for this purpose.

EFFECT: object of present invention is to improve retention of solid substance, dehydration and texture, especially in the manufacture of paper and cardboard products.

19 cl, 5 tbl

FIELD: chemistry.

SUBSTANCE: loosening surfactant includes one or more linear or branched monoalkylamines, a linear or branched dialkylamine, a linear or branched tertiary alkylamine, an ethoxylated alcohol, a linear or branched, saturated or unsaturated hydrocarbon surfactant, a fatty acid amide, a quaternary ammonium salt of a fatty acid amide, a quaternary ammonium salt of dialkyl dimethyl, a quaternary ammonium salt of dialkyl imidazoline, a quaternary ammonium salt of dialkyl ether, triethanolamine-di-tall oil fatty acid, fatty acid dialkylamide, C16-C18 unsaturated alkyl alcohol ethoxylate, a compound having registration number CAS 68155-01-1, a compound having registration number CAS 26316-40-5, or a combination thereof.

EFFECT: disclosed is a method of producing a sheet of loose cellulose, which includes forming a cloth containing loose cellulose fibres and depositing at least one loosening surfactant onto the cloth to obtain a sheet of loose cellulose.

27 cl, 1 dwg, 1 tbl

FIELD: medicine, pharmaceutics.

SUBSTANCE: invention relates to nano-fibrillar cellulose gels, intended for wide application in industry and in wound healing. A method of their production includes (a) preparation of cellulose fibres; (b) preparation of at least one filler and/or pigment; (c) combination of the cellulose fibres and the filler and/or pigment; (d) fibrillation of the cellulose fibres in the presence of at least one filler and/or pigment to formation of gel from primary fibrils, the filler and/or pigment are selected from the group, including precipitated calcium carbonate, natural crushed calcium carbonate, dolomite, talc, bentonite, clay, magnesite, satin white, sepiolite, huntite, diatomite, silicates and their mixtures. A nano-fibrillar cellulose gel, obtained by the method described above and its application are also described.

EFFECT: invention provides the increased productivity of nano-fibrillar cellulose gels with energy efficiency of production.

16 cl, 8 dwg, 2 tbl, 9 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing microfibrillated cellulose. The method of producing microfibrillated cellulose includes: providing a suspension containing cellulose fibres; treating the suspension with an enzyme; mechanically treating the suspension to break down the fibres, wherein mechanical treatment and enzyme treatment is carried out simultaneously in a single treatment step, said treatment step ranging from 15 minutes to 25 hours.

EFFECT: obtaining microfibrillated cellulose using an improved method which is efficient in terms of power saving.

7 cl, 2 dwg,1 ex

FIELD: chemistry.

SUBSTANCE: method of obtaining monocrystalline cellulose includes cellulose destruction, washing the product with water and bases, drying. A cellulose-containing material is processed with solutions of heteropolyacids in water, solutions of heteropolyacids in lower aliphatic carboxylic acids or in water mixtures of carboxylic acids with any ratios water-carboxylic acid without an addition of mineral acids at a temperature of 100-120°C for 15-120 minutes with the concentration of heteropolyacids of 0.1-15 mol.%.

EFFECT: invention makes it possible to simplify and reduce the process duration, increase efficiency, manufacturability and ecological compatibility of the MCC manufacturing.

FIELD: chemistry.

SUBSTANCE: method for cellulose delignification and bleaching with chlorine dioxide and hydrogen peroxide in the presence of molybdate or tungstate as a catalyst. The bleaching step includes: a) a first step where cellulose (3-30 wt %) in an aqueous mixture at temperature in the range of 50 to 150°C and pH in the range of 2 to 7 reacts with chlorine dioxide in an amount which corresponds to a Kappa coefficient in the range of 0.02 to 0.25 until more than 90% chlorine dioxide is converted; b) a second step where the mixture obtained at the first step, without separating components thereof, reacts at temperature in the range of 50 to 150°C with hydrogen peroxide which is taken in amount of 0.1 to 5 wt %, in the presence of molybdate in an amount which corresponds to molybdenum content of 10 to 2000 ppm, or in the presence of tungstate in an amount which corresponds to tungsten content of 200 to 10000 ppm. All amounts in each case are given with respect to the mass of the dry cellulose used.

EFFECT: improved whiteness of cellulose, low consumption of chlorine dioxide without undesirable destruction of cellulose, high resistance of cellulose to yellowing.

10 cl, 10 tbl

FIELD: chemistry.

SUBSTANCE: claimed invention relates to method of obtaining nanocellulose, which includes modification of cellulose fibres. method includes the following stages: i) processing cellulose fibres for, at least, five minutes with aqueous electrolyte-containing solution of amphoteric or anionic carboxymethylcellulose (CMC), where the temperature in the process of processing constitutes at least 50°C, and at least one of the following conditions is fulfilled: A) pH value of aqueous solution in the process of processing is in the interval about 1.5-4.5; or B) pH value of aqueous solution in the process of processing is higher than about 11; or C) concentration of electrolyte in aqueous solution is in the interval about 0.0001-0.5 M, if electrolyte has monovalent cations, or in the interval about 0.0001-0.1 M, if electrolyte has bivalent cations, ii) setting pH in the interval of pH values from about 5 to about 13 by application of basic and/or acidic liquid and iii) processing said material in mechanical crushing device and obtaining nanocellulose in such way. If amphoteric CMC is applied, at least 23.6 mg/g of CMC are added, and in case anionic CMC is applied, at least 61.6 mg/g of CMC are added.

EFFECT: application of method of nanocellulose production in accordance with claimed invention prevents clogging of mechanical devices.

13 cl, 7 dwg, 1 ex, 1 tbl

FIELD: textiles, paper.

SUBSTANCE: method is carried out by successive soaking of cellulose raw material in alkaline solution thermo-mechanical chemical processing, extraction, washing, bleaching, extraction, washing, extraction and drying, and herbaceous plants are taken as the cellulose raw material. Before drying the cellulose raw material is loosened to individual fibres, transported on screws in which the diffusion alignment is carried out on moisture by volume, followed by drying in a microwave unit.

EFFECT: invention enables to reduce energy costs and to obtain cellulose which is uniform on quality characteristics.

10 cl, 3 ex, 1 tbl

FIELD: chemistry.

SUBSTANCE: raw material undergoes steam treatment before the cooking step. Cellulose obtained by cooking, undergoes cold caustic extraction (CCE) during subsequent treatment.

EFFECT: invention enables to obtain cellulose with high output and purity of the product, and avoid accumulation of hemicellulose in the bleaching filtrate.

21 cl, 7 ex, 9 tbl, 13 dwg

FIELD: chemistry.

SUBSTANCE: method of obtaining alkaline cellulose involves a step for providing a cellulose mass, which contains cellulose fibres with free space between fibres, and treating said cellulose mass with an alkali to obtain alkaline cellulose. Alkaline treatment takes place in the presence of an expander which is capable of penetrating the space between cellulose fibres. The expander is a hydrophilic polymer which can be dissolved or dispersed in aqueous solution.

EFFECT: high reaction capacity of cellulose mass.

12 cl

FIELD: cellulose production.

SUBSTANCE: invention relates to manufacture of cellulose from cotton lint after alkali pulping or from prehydrolyzed wood cellulose and can be utilized in paper-and-pulp industry or in manufacture of artificial fibers, films, and other cellulose materials. Pulped cotton lint or prehydrolyzed wood cellulose is bleached by sodium hypochlorite at modulus 1:20 to 1:30 and 20-30°C, washed, treated for 50-60 min with 1.0-1.5% sodium hydroxide solution at 80-90°C, and subjected to souring, after which desired product is recovered. More specifically, cotton lint after alkali pulping is bleached in two steps separated by washing. In the first step, bleaching is carried out for 0.5-2.0 h at active chlorine concentration 0.3-2.0 g/L and, in the seconds step, for 0.5-6.0 h with 1.0-6.0 g/L active chlorine concentration. Prehydrolyzed wood cellulose is leached in one step for 0.5-6.0 h with 0.3-6.0 g/L active chlorine concentration.

EFFECT: improved quality of product, reduced average degree of polymerization, and increased reactivity thereof.

2 tbl, 18 ex

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