Method of isolation of carbon nanoparticles
 Method of obtaining carbon nanomaterial and carbon nanomaterial / 2502668Invention can be used in production of catalysts, electrodes, current-conducting elements, filters. Solid polytetrafluoroethylene (PTFE) is subjected to hydrolysis without access of air in plasma of pulse high voltage electric discharge at atmospheric pressure with pulse amplitude not lower than 9 kV. Obtained carbon material with ordered nanostructure contains structural elements in form of defluorinated partially graphitised supramolecular chain structures of PTFE 30-100 nm thick, formed by fibres with diameter 1-2 nm, woven in random way into homogeneous porous mass with pore size 1-2 nm. |
 Method of obtaining graphene film / 2500616Invention can be applied in production of transparent electrodes and instruments of nano-electronics. Graphene film is obtained by sedimentation of carbon from carbon-containing gas in vacuum on catalyst-covered substrate, preliminarily heated to temperature, which exceeds carbon-containing gas decomposition. Carbon-containing gas is supplied to pressure 1-10-4 Torr. Exhaustion of reactor is carried out 1-300 s after supply of carbon-containing gas with its simultaneous cooling to room temperature at rate 10-100°/min. As carbon-containing gas, taken is gas, selected from the group: acetylene, methane, ethane, propane, butane, ethylene, hexane or combination of said gases with inert gas. As catalyst, applied is metal, selected from the group: Fe, Ni, Cu or combination of metals, which includes at least two of upper mentioned metals. Catalyst film is 1-5000 nm wide. |
 Electro-chemical method of graphene obtaining / 2500615Invention can be applied in electro-chemical and electro-physical devices. Anodic galvanostatic polarisation of titanium and zircon is performed with current density from 0.1 to 3.0 mA·cm-2 in liquor of chlorides of alkaline metals, with contain from 0.1 to 1.0 wt % of boron carbide powder at temperature 843-873 K in argon atmosphere. |
 Reinforcing frame made of carbon-carbon composite material / 2498962Reinforcing frame made of carbon-carbon composite material is in form of a four-directed spatial structure with a hexagonal transverse-isotropic layout of reinforcing elements. The reinforcing elements are used twisted carbon fibres. The layout of transverse layers is made of fibres (7) with linear density γt=(300-420) tex, and the hexagonal layout is made of fibres (8) with linear density γg=(3÷4)·γt. The distance between the closest reinforcing elements in each transverse layer is equal to the thickness of the fibre with linear density γg, and the distance between transverse layers of the same direction is equal to 2δ, where δ is the thickness of the fibre with linear density γt. |
 Method of obtaining long carbon nanopipes and device for thereof realisation / 2497752Invention can be applied in production of highly strong complex carbon threads and composition materials for auto- and/or aircraft construction. Carbon-containing component, activator and precursor of catalyst of growing carbon nanopipes are introduced in flow of gas-carrier through device for their introduction with formation of mixture. Obtained mixture is passed through vertical reactor with work chamber, heated to 1000 to 1200 °C by device for its heating. Formed nanopipes are brought out into product receiver. Mixture is supplied into reactor from bottom to top with linear speed from 50 to 130 mm/s. When said work temperature is reached in mixture flow, its linear speed is reduced to 4-10 mm/s, and before output from reactor is increased to 30-130 mm/s. Chamber of reactor is made from three successive sections - lower input 16, middle 17 and upper output 18. Diameter of section 16 constitutes from 1/3 to 1/5 from section 17 diameter, and diameter of section 18 constitutes from 1/3 to 1/4 of section 17 diameter. Output of device for mixture supply into work chamber is connected with input of lower input section 16. |
 Fullerenol c60 and method of its obtaining from glycerin / 2497751Invention can be applied in production modifiers of epoxy composites, microbiocides with anti-HIV activity, which do not demonstrate cytotoxicity, and anditoxidant additives to cosmetic preparations. Fullerenol C60 is obtained by catalytic dehydration of glycerin with heating. As catalyst applied are glucose, fullerene, fullerenol. Formed reaction water, allyl alcohol and acrolein are distillated. Dehydration is carried out until solid phase of black colour is formed and volume of reaction solution is reduced to 20-25% of initial glycerin volume. Formed fullerenol C60 is separated from diluted by water reaction solution in form of solution of sodium or ammonia salt by addition of alkali or ammonia, filtered from synthesis byproduct-water-insoluble carbon. Filtrate is acidified by sulfuric acid to pH 6.5, and precipitated in the process of acidification sediment, which represents fullerenol C60, is filtered and washed with water from unreacted glycerin, remains of allyl alcohol, acrolein, sodium or ammonia sulphate, which are formed in the process of acidification. Filtered sediment of dark-brown colour, representing fullerenol C60, is dried at temperature 70-90 °C. Additional purification is carried out by recrystallisation from alcohol. Fullerenol C60 is soluble in water and alcohol. |
 Method of producing carbon nanostructured materials / 2496713Invention can be used in producing materials for electronics, additives for rocket fuel, catalysts, lubricating oil and polymer coatings. A climatic chamber 1 is pre-cooled by a cooling apparatus 4 to subzero temperatures. Water vapour produced by a generator 5 is then released into the chamber 1. The supercooled water vapour is artificially deposited on natural crystallisation centres in the air and ice crystals are formed, which are deposited in a collector 7 and removed from the chamber 1. A mixture of particles of carbon nanostructured materials with electric arc soot is then obtained in the apparatus 3 by arc sputtering of the starting material in an atmosphere of an inert gas. The obtained mixture is mixed with the medium of the chamber 1 and ice crystals are obtained due to selective condensation of the supercooled water vapour on particles of the carbon nanostructured materials. The end product is extracted by depositing ice crystals in the collector 7, removing from the chamber 1, heating and evaporating water. Selective condensation is carried out at atmospheric pressure and temperature in the chamber 1 of minus 5°C to minus 35°C under the condition Ei<e<Ew, where e is water vapour tension in the chamber, Ei and Ew are the saturating water vapour tension over ice and water, respectively. |
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Method of producing mixture of fullerenols / 2495821 Invention relates to chemical industry. Fullerene-containing soot is mixed with a liquid which reacts with fullerenes in the soot, e.g. with an aqueous alkali solution with concentration of at least 0.5 wt % selected from KOH, NaOH, Ba(OH)2 and/or hydrogen peroxide H2O2, with ratio thereof to soot of 1:(20-300) ml/g. The obtained mixture is mixed with a solution of a catalyst for hydroxylation of fullerenes - tetrabutylammonium hydroxide with concentration of 5-20 wt % in volume ratio to the mixture of 1:(100-400). After mixing, the mixture is filtered to separate spent soot from the obtained solution, in which a salting out agent is added, e.g. methanol CH2OH, or a mixture of propanol n-C3H7OH, diethyl ether C2H5OC2H5 and n hexane C6H6. The mixture of fullerenols precipitates, and the precipitate is washed in a Soxhlet apparatus, after which the dry mixture of fullerenols is separated. |
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Dispersion of carbon nanotubes / 2494961 Invention can be used in obtaining modifying additives for construction materials. Dispersion of carbon nanotubes contains, wt %: carbon nanotubes 1-20; surface-active substance - sodium salt of sulfonated naphthalene derivative 1-20; aerosil 5-15; water - the remaining part. Dispersion can additionally contain ethylene glycol as antifreeze. |
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Composition to reinforce building structures / 2493337 Composition comprises glass or basalt roving in amount of 90-100 wt parts, impregnated with polymer binder based on epoxide-diane resin in the amount of 18÷20 wt parts. The polymer binder additionally contains a magnetic-susceptible metal-containing carbon nanostructure in the amount of 0.001÷1.5 wt parts. |
 Method for preparing water suspension of biocompatible porous silicon particle / 2504403Invention refers to a method for preparing a water suspension of silicon nanocrystalline particles for biomedical applications. The declared method is characterised by the fact that a porous silicon film of the thickness of 1 to 100 mcm and the porosity of 50 to 80% is formed on the surface of silicon plates. The film is formed by electrochemical etching in a solution containing 40-50% aqueous solution of fluoric acid and alcohol in ratio 1:1 to 1:5 for a period of time of 10 to 60 minutes at specific current 20 to 60 mA/cm2. The prepared silicon plates coated with a porous silicon layer is washed in distilled water, dried and placed in a container with distilled water. Then, they are exposed to ultrasound for more than 10 minutes at the intensity of the silicon plate exposure in water of 100 Wt/cm2 at frequency 23 kHz. This provides forming the stable suspension in distilled water from nanoparticles of the lateral dimension of 10 to 500 nm. |
 Nanostructured titanium-nickel alloy with shape memory effect and method of making bar thereof / 2503733Proposed alloy features structure of nanocrystalline grains of B2-phase wherein volume fraction of 0.1 mcm-size grains and those of shape factor of 2 in mutually perpendicular planes makes at least 90%. Over 50% of grains have large angular boundaries misaligned relative to adjacent grains through 15 to 90 degrees. Method of making the bar from said alloy comprises thermomechanical processing including plastic straining and recovery annealing. Intensive plastic straining is made in two steps. At first step, equal-channel angular pressing is made to accumulated strain e≥4. At second step, forge ironing and/or drawing are made. Annealing is carried out either in process and/or after every straining step. Equal-channel angular pressing is performed at 400°C. Forge drawing and ironing are made to total reduction of over 60% at gradual decrease of temperature to t=450-200°C, while annealing is performed at t=400-200°C. |
 Luminescent ink for cryptographic protection of documents and articles from falsification, methods for application thereof and methods of verifying said articles / 2503705Luminescent protective ink contains a solvent and semiconductor nanocrystals dispersed in an organosilicon compound, consisting of successively arranged: semiconductor nucleus 1, first 2 and second 3 semiconductor layers and an outer 4 layer, the material of which is selected from an organosilicon polymer from a series which includes poly(aminoethyl)trimethoxysilane, poly(methacryl)triethoxysilane, poly(methyl) triethoxysilane, poly(mercaptoethyl) triethoxysilane, methyl-phenyl polysiloxane, polyethoxysilane. The semiconductor nanocrystals emit a fluorescent signal in a fluorescence wavelength range of 400-3000 nm under the effect of a visible or UV light source; the relative fluorescence quantum efficiency is at least 80%. |
 Method of obtaining stabilised water sol of nanocrystalline cerium dioxide, doped with gadolinium / 2503620Invention relates to technologies of nanomaterials production for obtaining of oxide fuel elements, thin coatings, films, which have high ionic conductivity. Method includes preparation of water solution of cerium and gadolinium salts, in which total concentration of rare earth elements constitutes 0.005÷0.02 mole per litre of water, and molar ratio of Ce:Gd constitutes from 19:1 to 4:1, addition of anion-exchange resin in OH-form to obtained solution until pH 9.0÷10.0 is reached, separation of formed colloidal solution from anion-exchange resin by filtering, hydrothermal processing at 120÷210°C for 1.5÷4 h and cooling to room temperature. Obtained unstable sol of nanocrystalline cerium dioxide, doped with gadolinium, is additionally stabilised with salt of polybasic acid (citric or polyacrylic) with molar ratio of rare earth elements in acid, equal 1:1÷4, and following slow drop-by-drop addition of ammonia water solution until pH 7÷8 is obtained. |
 Cleaning method of carbon nanomaterial from metal-containing catalyst / 2502833Cleaning is performed by dilution of a catalyst with different reagents in an electrolysis unit, the cathode and anode space of which is divided with a membrane. Cleaned carbon nanomaterial (CCN) is located in anode space of electrolysis unit. As electrolyte there used are water solutions of substances, at electrolysis of which in anode space of electrolysis unit an accumulation of reactive anions forming water-soluble salts with catalyst takes place. |
 Vacuum unit for making nanostructured coats with shape memory effect on part surface / 2502829Proposed unit comprises frame to support vacuum chamber communicated with vacuum pump, part fixture, gas flame torch for high-rate gas-dynamic sputtering arranged at 45 degrees to part surface, feeder of powder with shape memory effect to gas-flame torch, pyrometer to measure part temperature, module for ion-beam cleaning, appliance for surface straining to produce nanostructured layer, step-down transformer for additional heating of part surface, device to cool part surface to temperature of martensitic transformation at surface straining, and control device. Proposed unit comprises extra two magnetrons and metal ion implantation source secured on in vacuum chamber to be directed towards processed part. Surface straining appliance is composed of the press with moving top crossbar and fixed bottom crossbar arranged inside vacuum chamber. Note here that part fixture and surface cooler are mounted at said bottom crossbar. Gas-flame torch is rigidly secured inside vacuum chamber. |
 Method of water treatment and device to this end / 2502680Invention relates to water treatment and can be used in whatever field. Initial water is filtered through sorbent containing graphene and/or carbon nanotubes and membrane including cylindrical or conical through 0.0050.3 mcm-dia pores. Proposed device comprises sorbent containing graphene and/or carbon nanotubes and membrane including cylindrical or conical through 0.0050.3 mcm-dia pores. Filtration element membrane is a track membrane. Membrane cylindrical pores are composed by carbon nanotubes. Invention allows to up efficiency and reliability of water treatment and to down costs. |
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Method of obtaining carbon nanomaterial and carbon nanomaterial / 2502668 Invention can be used in production of catalysts, electrodes, current-conducting elements, filters. Solid polytetrafluoroethylene (PTFE) is subjected to hydrolysis without access of air in plasma of pulse high voltage electric discharge at atmospheric pressure with pulse amplitude not lower than 9 kV. Obtained carbon material with ordered nanostructure contains structural elements in form of defluorinated partially graphitised supramolecular chain structures of PTFE 30-100 nm thick, formed by fibres with diameter 1-2 nm, woven in random way into homogeneous porous mass with pore size 1-2 nm. |
 Method of producing nano-structure commercially pure titanium for biomedicine / 2501882Proposed method comprises processing the workpiece in explosive accelerator by high-velocity Ti powder particle flow in the mode of super deep penetration of particles. Note here that Ti particles are arranged under explosive with air gap. Acceleration of articles is carried out by shock wave in accelerator guide channel coupled with processed workpiece. Processing is performed by flow of particles with dispersity of 20 mcm at flow rate of 1.5-2.5 km/s, density of 1 g/cm3, pressure of collision of particles with workpiece material of 12-15 GPa and their interaction time of 5-7·10-5 s. |
 Producing method of nanocrystalline silicon-replaced hydroxyapatite / 2500840Producing method of monophasic nanocrystalline silicon-replaced hydroxyapatite involves synthesis of silicon-containing hydroxyapatite by means of a method for deposition from water solution of reagents containing orthophosphoric acid, calcium hydroxide and tetraethyl orthosilicate at pH of not less than 9 and molar ratio of Ca/P in the range of 2.0 to 2.5; sedimentation for completion of a phase formation process, extraction of deposit, drying and heat treatment of deposit; with that, synthesis is performed by adding 10-20% solution of orthophosphoric acid at the speed of 0.2-0.8 ml/min per litre of water solution of calcium hydroxide / tetraethyl orthosilicate composition prepared by means of 0.08-0.16% water solution of calcium hydroxide and design amount of tetraethyl orthosilicate to obtain a finished product with silicon replacement degree x equal to 1-2 and molar ratio of Ca/(P+Si), which is close to 1.67, and heat treatment is performed at the temperature of not lower than 300°C, but not higher than 400°C. Invention allows obtaining stoichiometric monophasic product of phases with average size of crystals of 9.95-12.53 nm, specific surface of 108.97-132.58 m2/g, and increased bioactivity, at the heating of which incidental phases do not occur. |
 Method of making structures on basis of semiconductor monocrystals and organic molecules / 2504430Invention relates to production structures based on semiconductor nanocrystals and organic molecules to be used as micro fluid elements ion optoelectronic devices. Proposed method consists in implanting nanocrystals and organic molecules in membrane track pores. Nanocrystals are implanted in track pore wall layer while organic molecules are bonded with modified or unmodified carboxyl groups on track membrane track pore inner surface. Or, molecules are bonded into complex with nanocrystals implanted in track membranes owing to impregnation of membranes with solutions of nanocrystals and organic molecules under normal conditions. |
FIELD: nanotechnology.
SUBSTANCE: invention can be used in deep processing of dust captured from flue gases of electrothermal production of silicon. It is repulped with water at a ratio of liquid to solid (15-20): 1 technogenic waste in the form of dust comprising carbon nanoparticles are processed with an aqueous solution of fluohydric acid with a concentration of 15-32%, neutralised with ammonia to a pH of 6.5-8.5. The pulp and the precipitation containing the nanoparticles are mechanically separated by two-stage centrifugation or two-stage filtration. The byproducts in the form of fluorinated solutions can be recycled to aluminium fluoride.
EFFECT: reduced energy costs, simplified technology of production of carbon nanoparticles, improved environment due to utilisation of previously stored wastes.
4 cl, 3 dwg, 1 tbl, 1 ex
The invention relates to the process of extracting carbon nanoparticles of a material containing silicon dioxide and carbon nanoparticles, and can be used in deep processing of dust captured from flue gases electrothermal production of silicon emitting contained nanoparticles.
The invention relates to the priority direction of development of science and technology "Nanotechnology and nanomaterials" (Alphabetical subject index to the International patent classification in priority directions of development of science and technology / YG Smirnov, E.V. Skidanov, S.A. Krasnov. - M.: PATENT, 2008. - p.19, p.33 [1]).
The conventional technology for the production of carbon nanoparticles from the carbon-containing material based on different, as a rule, high-energy impacts on the carbon-containing material in order to facilitate the breaker and the selection of particle size on the order of 10-9m
Known "Method of producing carbon nanotubes and device for its implementation" (patent RF №2337061, SW 31/02, WV 3/00, 2008, [2]). Carbon nanotubes receive an arc discharge between placed in the cell cathode and anode having a longitudinal channel through which pass the inert gas, heating the portion of the cylindrical surface of the anode currents are high frequent is you, as the inert gas from the camera selected in the cooling unit and then fed it back into the longitudinal channel of the anode to cool.
In this technology the carbon evaporated from the surface of the anode with the application process electrical degradation in inert atmosphere.
Sign analogue, coinciding with the essential features of the proposed method is the use of finely dispersed pulverulent phase carbon, formed after the destruction of the source electrodes, for allocation of nanostructures.
Known technology requires significant energy cost of implementation and complicated equipment.
A known method of producing fullerenes (closed surface structure, including 5-6 rings of carbon atoms) (patent RF №2240978, SW 31/02, 2004, [3]), including the grinding of natural materials-stones to the dispersity of from 2 to 0.005 μm-1the heat treatment in vacuum or in inert gas in the range of 100-1800°C at a rate of rise of temperature of 10-60°C/min, manual condensation sublimated fullerene with the temperature difference between the levels of 200-400°C. Shungite before use may be enriched by the carbon component of the gravitational and/or chemical methods.
Signs of similar, coinciding with the essential features of the claimed method is, is only of technical nature.
Known technology also requires significant energy cost of implementation and complicated equipment. The disadvantages of the technology include the small yield of the target product.
In contrast to the known solutions according to the patent of Russian Federation №2337061 and RF patent No. 2240978, in the inventive solution destructive preparing the carbonaceous feedstock is in the process of electro-thermal receipt silicon directly in industrial production using carbon materials as electrodes and reducing agents. In the present method the source of carbon nanoparticles is dust silicon production. To extract the carbon nanoparticles of this material is only required additional treatment for cleaning and removing this material. This treatment does not require significant energy and material costs, special sophisticated equipment to obtain the target product.
The known method for the production of carbon nanoparticles by laser ablation of carbon targets (Kozlov GI, technical physics Letters, 2003, vol. 29, VIP, 88-94 [4]). The material is exposed to laser radiation of high power, resulting in the evaporation of atoms and clusters from the surface and their subsequent condensation of the nanoparticles.
Sign analogue, coinciding with the essential features of the proposed method is the use of finely dispersed pulverulent phase carbon, formed after the destruction of the source electrodes, for allocation of carbon nanoparticles.
The disadvantage of this method is the need to maintain a high degree of vacuum in the reactor, significant energy costs, the uncertainty of the concentrations and composition of ablation products.
There is a method of producing carbon nanotubes using electrochemical degradation of carbon electrodes by generating arc discharge between carbon hollow anode and cathode, and a hollow anode move, and the arc discharge is carried out in air or an oxidizing atmosphere (Japan patent JP 2004189501, C01 In 31/02, SW 31/00, 2004[5]).
Sign analogue, coinciding with the essential features of the proposed method is the use of finely dispersed pulverulent phase carbon, formed after the destruction of the source electrodes, for allocation of carbon nanoparticles.
The disadvantages of the known solutions are high energy costs and the high cost of the obtained nanostructures because of their low content in the target product - cathode Deposit.
A method of obtaining nanopart the th material from shungite, including the processing of inorganic acid and heat treatment, in which shungite consistently when heated handle molten alkali, concentrated inorganic acid, which uses hydrofluoric acid (HF) or hydrochloric acid (HCl), a strong oxidant from a number of HClO4, VAO2after processing each of the reagents formed intermediate product is washed with water and dried, and heat treatment is carried out by high-temperature gas-phase oxidation to obtain the desired product (RF patent No. 2307068, SW 31/02, WV 3/00, published 27.09.2007, [6]).
The disadvantages of the known solutions should include energy costs for heat treatment of material in the process, the use of molten alkali and boiling concentrated acids, which significantly complicates the process and will require the creation of a system of gas purification and recycling of used reagents and by-products. As the feedstock use of natural material (shungite), which will require additional costs for the production, transportation, and possible additional technological preparation of this material, which greatly increases the cost of manufacturing nanocarbon material.
There is a method of allocating carbon nanocast the carbon material, includes treatment of the material with a solution of acid and heat treatment, in which the carbon material used precipitate formed after leaching solid ftoroplastsoderzhashchikh waste electrolytic aluminium production, processing sediment lead in an aqueous solution of an organic acid with a concentration of 1.0 to 1.5% at a temperature of 60-80°C with getting mud and sludge, treated sludge is carried out at a temperature of 500-580°C, and then produce Reformirovanie material to the ratio of W: T not less than 5:1, carry out ultrasonic treatment of pulp and mechanical dvukhstadiinoe separation of the pulp to obtain the target product, carbon sludge and solution.
The organic acid can be used oxalic acid, heat treated sludge are within 1.0 to 1.5 h, ultrasonic treatment of the pulp are in a period of not less than 0.3 h, Reformirovanie material produced water or ethyl alcohol, mechanical separation of slurry conduct a two-step centrifugation or two-stage filtering or first stage of filtration or by decantation, and the second phase by centrifugation (RF patent No. 2433952, SW 31/00, WV 3/00, published on 20.11.2011, [7]).
On purpose, technical nature, the presence of similar features this solution is selected as the nearest equivalent.
The disadvantages of the known solutions should include significant energy costs for the preliminary preparation of the material - leaching solid ftoroplastsoderzhashchikh waste electrolytic production of aluminum, the heat treatment of the material in the process, ultrasonic treatment of the pulp, which increases the cost of manufacturing nanocarbon material.
The objective of the proposed technical solution is the improvement of technical and economic indicators of the process of allocating carbon nanoparticles.
The technical result of the invention is to reduce energy costs and simplifying the process of extracting carbon nanoparticles through the use of technogenic raw materials - waste electrothermal production of silicon already exposed to electric arc.
Technical results achieved by the fact that in the method of allocation of carbon nanoparticles from man-made waste containing carbon nanoparticles, including Reformirovanie source material, the processing solution of acid and mechanical separation of slurry separating the precipitate containing nanoparticles, the carbonaceous material containing carbon nanoparticles, use of technogenic waste in the form of dust captured from exhaust gases of electrothermic is anyone silicon production, the processing of the pulp are solution of hydrofluoric acid concentration of 15 to 32%, and before mechanical separation of slurry separating the precipitate containing carbon nanoparticles, led by its neutralization with ammonia to a pH of 6.5 to 8.5.
In this case, Reformirovanie material can be produced by water, and the ratio of liquid to solid support 15-20: 1, and the mechanical separation of slurry separating the precipitate containing the carbon nanoparticles can be carried out by two-step centrifugation or two-stage filtering.
The claimed solution and the solution closest analogue is characterized by a similar significant features:
the method of allocation of carbon nanoparticles;
- use as source material technogenic waste containing carbon nanoparticles;
- Reformirovanie material water;
treatment material containing carbon nanoparticles, an acid solution;
mechanical separation of slurry separating the precipitate containing nanoparticles.
The proposed solution is also characterized by signs, other than signs closest equivalent:
as a material containing carbon nanoparticles, use of technogenic waste in the form of dust captured from flue gases electrothermal production of silicon;
- obrabatyvali, containing carbon nanoparticles, a solution of hydrofluoric acid;
treatment of the pulp with a solution of hydrofluoric acid concentration 15-32%;
- neutralization of the slurry ammonia before mechanical separation of the reaction mixture, separating the precipitate containing carbon nanoparticles;
- neutralizing the slurry with ammonia up to a pH of 6.5 to 8.5.
In this case, Reformirovanie material can be produced by water, and the ratio of liquid to solid support 15-20: 1, and the mechanical separation of slurry separating the precipitate containing the carbon nanoparticles can be carried out by two-step centrifugation or two-stage filtering.
Formed by neutralizing the slurry with ammonia fluorosilicate preparation of ammonium (NH4)2SiF6in the future it may be used for the production of high-purity silicon dioxide, nitrogen fertilizer and aluminum fluoride.
The presence of the proposed solution characteristics different from the characteristics of the solution closest analogue, allows to make a conclusion about the relevance of the proposed solutions to the condition of patentability "novelty."
The technical essence of the proposed solution is as follows.
In the proposed solution, to reduce the energy costs of the process and cost of expensive about what the equipment is designed, as source material for separation of nanoparticles using dust captured from flue gases electrothermal production of silicon.
The dust captured from flue gases electrothermal production of silicon, is formed in amounts equivalent to the obtained silicon, that is, tens of thousands of tons per year. Dust contains silica and carbon, including carbon nanoparticles, and a low content of impurities of iron and other elements (Chernyakhovsky L.V., Baranov A.N., Shishkin G. A. Application of waste silicon, aluminum and chemical industries with the aim of obtaining silicon and ferrosilicon // Problematic issues of the East-Siberian region. Sbsaustralia - Irkutsk: Publishing house of Irkutsk state technical University - 2001, p.59-61 [8]).
Part of the dust production of silicon carbon is of interest, as the last transformation on the structuring process electrothermal production of silicon. The process is characterized by high power consumption (current 55 kA and voltage 170-180B), the temperature of the charge of 1300-1600°C and the temperature in the arc zone to 6000°C. In the process of destruction of the surface of the electrodes and reducing agents is the removal of individual single-layer and multilayer graphite planes followed by the formation of nanostructures. Another possible mechanism of formation of carbon nanoose the tov is the pyrolysis gases, what is happening when restoring silicon carbon materials. The resulting finely dispersed nanoparticles are carried with the gas stream and recovered in the gas purification system together with particles of silicon dioxide. Carbon leaving in the dust silicon production is at the level of 5-25% and the results of studies using transmission electron microscope contains 50-90% of carbon nanostructures (see Fig. 1-3).
Task is the separation of carbon and silicon dioxide and the allocation of nanoparticles. The proposed technical solution, this problem is solved as follows. In the first stage, for the Department of silicon dioxide, is its dissolution in hydrofluoric acid concentration of 15.0-32.0 per cent. This process is performed in acid-resistant equipment. For further processes in unprotected equipment is neutralized slurry with ammonia. Ammonia is selected as the substances do not produce insoluble compounds under these conditions. The overall reaction is:
SiO2+6HF+2NH3=(NH4)2SiF6+2H2O
Excess hydrofluoric acid is neutralized with ammonia:
HF+NH3→NH4F
The resulting salts are soluble in water, the carbon-containing component remains in the sediment.
Completes processing of mechanical TLD is staged separation of the pulp to obtain the target product, carbon sludge and liquid. Mechanical two-stage separation of the pulp can be carried out a two-step centrifugation, two-stage filtration, filtration or decantation of the first stage and centrifugation in the second stage. Selected in the second stage of mechanical separation material is a carbon nanoparticles with typical sizes of the order of 20-100 nm, as shown by the results of studies by transmission and scanning electron microscopy, in the form of nanotubes and toroidal (see Fig.1-3).
The obtained nanoparticles can be used as a modifier of ferrous and non-ferrous metals, composites and building materials.
Comparative analysis of the proposed technical solutions with other known solutions in this area revealed the following.
Use as a raw material of technogenic waste silicon production, already passed through the processing electric arc at high temperatures has allowed to reduce the price of the final product is a concentrate of carbon nanostructures. Processing the source material with a solution of hydrofluoric acid was able to completely get rid of compounds of silicon and associated trace metals.
Neutralization of the reaction mixture with ammonia allowed to get fluorosilicate preparation of ammonium(NH 4)2SiF6, which later can be used for the production of high-purity silicon dioxide, nitrogen fertilizer and aluminum fluoride. Two-stage centrifugation secured concentrate carbon nanoparticles with typical geometrical dimensions of the order of 20-100 nm.
In the comparative analysis revealed no technical solutions, characterized by a set of features similar set of features characterizing the proposed technical solution, which allows to make a conclusion about the relevance of the proposed solutions to the condition of patentability "inventive step".
The proposed technology is as follows.
Example 1.
200 g of dust captured from flue gases electrothermal production of silicon composition, wt.% SiO2by 89.5; S - 9,2; other 1.3 was repulpable 3 l of cold distilled water, and then slowly added 1.5 l of hydrofluoric acid concentration of 27.0%. With increasing temperature up to 80°C was added ice. After 2 hours of repulpable spent neutralization with aqueous ammonia to a pH within the 6.5 to 8.5. The slurry was centrifuged 30 minutes, 2500 rpm (relative centrifugal acceleration 1032 g, where g=9.8 m·s-2- acceleration of free fall). The precipitate was repulpable when the ratio of liquid to solid equal to 5K 1 and re-centrifuged. After drying the precipitate in the amount of 18.7 g, which is the target product.
In the analysis of scanning electron microscope found that the precipitate on 50-90% of the nanoparticles in the form of nanotubes and toroids.
Example 2.
200 GPIO captured from flue gases electrothermal production of silicon composition, wt.% SiO2- 92,5; - 5,8; other 1.7 was repulpable 3 liters of cold water, then slowly added 1.4 l of hydrofluoric acid concentration of 32.0%. With increasing temperature up to 80°C was added ice. After 2 hours of repulpable spent neutralization with aqueous ammonia to a pH within the 6.5 to 8.5. The slurry was centrifuged 30 minutes, 2500 rpm (relative centrifugal acceleration 1032 g, where g=9.8 m·s-2- acceleration of free fall). The precipitate was repulpable when the ratio of liquid to solid equal to 5 to 1 and re-centrifuged. After drying the precipitate in the amount of 12.5 g, which is the target product.
When the analysis revealed that the precipitate on 50-90% of the nanoparticles in the form of nanotubes and toroids.
Technological parameters of processing of the material on the proposed method for production of nanoparticles is established experimentally and presented in table 1.
As can be seen from the table, the most appropriate concentration of hydrofluoric acid is from 15.0-32.0 per cent. At lower concentrations netetiquette complete dissolution of silicon dioxide, more concentrated acid does not improve the process, but it is costly.
If repulpable dust with a ratio of liquid to solid is not less than 15 to 1, the process goes very rapidly to boiling and discharge of the reaction mass, so repulpable recommended within the ratio of liquid to solid at the level of 15-20 to 1. At a higher dilution of the reaction going at a low temperature and in the sediment remains silicon dioxide.
Depending on the composition of the starting material used reagents for acid treatment and reformirovania, characteristics of the equipment used, process parameters can be changed in the claimed range.
The proposed technology allows to dispose of the dust captured from flue gases electrothermal production of silicon, not processed and directed to present in sludge, which is the potential (and sometimes real) sources of environmental hazard for the environment.
Additional product implementation of the proposed technology is a solution of ammonium fluorosilicate preparation, which can be processed by known technologies for high-purity silicon dioxide, nitrogen fertilizer or aluminum fluoride.
| Table 1 | ||||||
| Processing dust production silicon in a hydrofluoric acid | ||||||
| The dust composition, wt.% | Technological processing options | The composition of the sludge after treatment, wt.% | ||||
| The ratio of liquid to solid | temperature processing | the concentration of hydrofluoric acid, % | SiO2 | Other | C | Other |
| SiO2by 89.5 | 15 to 1 | 60°C | 10,0 | 1,2 | 96,1 | 2,7 |
| S - 9,2 | 15 to 1 | 80°C | 15,0 | 0,4 | to 97.1 | 2,5 |
| Other - 1,3 | 15 to 1 | 80°C | 27,0 | 0,2 | 97,3 | 2,5 |
| 15 to 1 | 80°C | 32,0 | 0,2 | 97,3 | 2,5 | |
| 10 to 1 | violent boiling | 27 | experience interrupted | |||
| 20 to 1 | 80°C | 27 | 0,2 | 97,3 | 2,5 | |
| 30 : 1 | 55°C | 27 | 1,4 | 95,9 | 2,7 | |
INFORMATION
1. Alphabetical subject index to the International patent classification in priority directions of development of science and technology / YG Smirnov, E.V. Skidanov, S.A. Krasnov. - M.: PATENT, 2008. - p.19, p.33.
2. RF patent №2337061, SW 31/02, WV 3/00, 2008
3. RF patent №2240978, SW 31/02, 2004
4. Kozlov g-I technical physics Letters, 2003, vol. 29, VIP, 88-94.
5. The Japan patent JP 2004189501, SW 31/02, SW 31/00, 204,
6. RF patent №2307068, SW 31/02, WV 3/00, 2007
7. RF patent №2433952, SW 31/00, WV 3/00, 20.11.2011,
8. Chernyakhovsky L.V., Baranov A.N., Shishkin G. A. Application of waste silicon, aluminum and chemical industries with the aim of obtaining silicon and ferrosilicon // Problematic issues of the East-Siberian region. Sbsaustralia - Irkutsk: Publishing house of Irkutsk state technical University - 2001, p.59-61.
1. The method of allocation of carbon nanoparticles from man-made waste containing carbon nanoparticles, including Reformirovanie source material, the processing solution of acid and mechanical separation of slurry separating the precipitate containing nanoparticles, wherein the material containing carbon nanoparticles, use of technogenic waste in the form of dust captured from flue gases electrothermal silicon production, processing, pulp lead with a solution of hydrofluoric acid concentration of 15 to 32%, and before mechanical separation of slurry separating the precipitate containing carbon nanoparticles, led by its neutralization with ammonia to a pH of 6.5 to 8.5.
2. The method according to claim 1, characterized in that Reformirovanie material produced water, and the ratio of liquid to solid support (15-20): 1.
3. The method according to claim 1, characterized in that the mechanical separation of slurry separating the precipitate containing carbon nanocat the Itza, conduct a two-step centrifugation.
4. The method according to claim 1, characterized in that the mechanical separation of slurry separating the precipitate containing carbon nanoparticles, conduct two-stage filtration.