The method of inoculation porous carbon material

 

The invention is intended for the adsorption engineering, electrical engineering and electronics and can be used to obtain active carbon electrode materials. Powder nanoporous carbon material with a volume of nanopores of 0.49 cm3/g and a specific surface area of 1330 m2/g is impregnated with a liquid oxidizing agent, for example, nitric acid with a concentration of 30-65%. Incubated at room temperature and a residual pressure of not more than 100 PA 15 minutes Impregnated powder is placed in a flask and poured acid. The mass ratio of acid : carbon material is 10:1. After incubation in a water bath at 80o2 h acid is drained. The powder is washed from acid to a pH of not less than 3, dried at 1105)oC. Determine the content of functional groups. It should be at least 1.0 mmol/g Heat treatment is carried out in argon at 300-800oWith heating rate 20oC/min, Incubated 1 h Cycle oxidation - heat treatment is repeated until reaching the desired size and pore volume. The invention allows to expand the range of absorbed substances to adjust the porous structure of the carbon material, to increase the volume and dimensions of the nanopores. 4 C.p. f-crystals, 1 Il., table 1. the particular active carbons, and can be used in the adsorption engineering, electrical engineering, electronics and other fields.

Active carbons are characterized by a high content of pores of size less thandue to which they have a high adsorption capacity. In practice, especially abroad, now for then, less thancommon is the term "nanopores". Therefore, active carbons can be considered carbon nanoporous materials. In practical application for these materials are important parameters of the porous structure. The parameters of the porous structure include the volume of the nanopores, their size distribution, specific surface area. The terms used to disclose the invention.

The use of nanoporous carbon materials in modern engineering fields, such as electronics, electronics and so on, requires the directed modification of the parameters of the porous structure, providing a carbon material with a variable volume, the average size of the nanopores, their size distribution.

A known method of modifying the pore structureid carbon or water vapor at a temperature of 850-900oWith [1]. This method achieved the development of the porous structure due to the chemical interaction of gaseous oxidizing agents carbon frame. Parameters of porous structure of carbon materials obtained in this way, substantially depend on the process conditions and raw material quality. Due to the fact that the process is carried out in the gas phase, diffusion factors have a great influence on the course of chemical reactions which result is the formation of nanoporosity. This makes it difficult to obtain materials with desired parameters of the porous structure. To exclude the effect of diffusion is preferable to carry out the process in the liquid phase.

There is a method of modifying carbon nanoporous materials by oxidation with nitric acid, which is the closest to the claimed solution [2]. The method includes processing a porous carbon material with concentrated nitric acid at 80oC for 2 h, washing and drying at 200oC for 4 hours. This method allows you to create on the surface of the nanopore acidic functional group and is used to obtain materials with improved sorption capacity in relation to Katie is ACA of the invention is to develop a method, enabling directional modifying the pore structure of nanoporous carbon material and ensure the expansion of the range of applications for which this material can be used effectively.

The technical result of the proposed method is to increase the amount and size of the nanopores, as well as expanding the range of absorbed substances.

The technical result is achieved due to the fact that the modification of carbon material containing pores with a size less than, exercise cycles, each of which comprises oxidizing in the liquid oxidants and subsequent processing in a non-oxidizing atmosphere at high temperature. The number of cycles is determined by the required volumetric content of nanopores or the size of the nanopores in the final product.

More preferably phase oxidation of carbon nanoporous material be done by processing it 30-65% nitric acid. As a non-oxidizing atmosphere, preferably argon, and the heat treatment be carried out in the temperature range 300-800oC.

When carrying out the oxidation with nitric acid of a concentration lower than 30%, there is no Tr is lateline, because difficulties arise when working with it because of the formation of gaseous oxides of nitrogen.

Heat treatment at temperatures below 300oWith no leads to changes in the porous structure of the material and at a temperature of 800oWith the inoculation process was completed.

The invention consists in the following. The oxidation of liquid oxidants such as nitric acid, is a chemical interaction of the surface carbon atoms with a hydrogen peroxide solution, which are formed of oxygen-containing functional groups. These groups can be phenoliccarboxylcarbonyllactonaseThe advantage of nitric acid as the liquid oxidizer is that this reagent acts on the basal plane graphite-like fragments that form the walls of the nanopores carbon nanoporous materials that can deliberately create functional groups formed on the defects on these planes.

Use for oxidation of liquid oxidizer, in particular nitric acid, provides a uniform oxidation of the entire surface the pressure is ensured regardless of the size of the sample including when processing large phone during subsequent heat treatment in an inert environment is the destruction of functional groups. This destruction begins at a temperature of approximately 300oWith, the sustainability of the groups depends on their structure. The least stable are carboxyl groups. Important is that the destruction occurs with the formation of gaseous carbon oxides co and CO2, i.e., during desorption of oxygen at the same time removed the carbon atoms from the surface of the nanopore. Thus there is an increase in the volume and size of the nanopores of the carbon material. After the first loop, if necessary, carried out the second and subsequent cycles to achieve the desired size and volume of the nanopores.

The invention is illustrated by the following examples.

Example 1. A portion of nanoporous carbon material in the form of a powder, the characteristics of which are presented in the table, soaked in nitric acid having a concentration of 65 wt.%. The impregnation is carried out at a residual pressure of not more than 100 PA at room temperature for 15 min to ensure penetration of the acid into all the nanoporous material. Then soaked in acid powder poured what about the flask is placed in a thermostatted water bath, heated to 80oC and maintained for 2 hours Then the acid is drained and washed the powder with distilled water to achieve a pH of wash water at least 3. Then the powder is dried at 1105)oC. Then determine the content of functional groups on the surface of the material. The material is then placed in a quartz flow reactor and carry out its processing argon by heating in the temperature range 300-800oWith heating rate 20oC/min, Then at a temperature of 800oWith stand for 1 hour. The specified processing, including phase oxidation with nitric acid and heat treatment in an inert atmosphere are repeated 3 times. After each treatment cycle to determine the parameters of the porous structure of the material.

The values obtained are given in the table.

Example 2. As the source material used nanoporous carbon material made in the form of discs with a diameter of 20 mm and a thickness of 1 mm Treatment is carried out analogously to example 1. Parameters of porous structure are presented in the table and in the drawing.

Material properties were determined by the following methods.

The content of functional groups after the stage of oxidation was determined what slotow, described in [2]. The volume of the nanopores was determined executory method for the adsorption of benzene in static conditions [3].

Specific surface area was determined from low-temperature nitrogen adsorption.

The distribution of the pore sizes were determined from the isotherms of low-temperature adsorption of nitrogen.

The presented data allow us to conclude that the proposed method modification leads to an increase in volume and size of the nanopores of the carbon material. Products according to the invention can find application for the absorption of organic substances, as electrode materials. The inventive method allows to expand the range of absorbed substances and to use high adsorption properties of carbon materials in areas that were previously inaccessible due to the large size of the molecules adsorbed substances. The proposed method allows you to adjust the porous structure of materials depending on the particular application and to create high-performance materials on the basis of cheap feedstock.

Sources of information 1. Calcev N. In. Fundamentals of adsorption technique. - M.: Chemistry, S. 262-264.

2. Jan Pawlaczyk, Halina Sobczak Badaniasorpcyjnychleczni coal. IV. The influence of oxidation on the sorption properties of carbo medicinalis // Acta polon. Pharm., XXXVII, No. 6, 1980 (Polska., RES eng., eng.), S. 655-661.

3. Calcev N. In. Fundamentals of adsorption technique. - M.: Chemistry, S. 33.


Claims

1. The method of inoculation porous carbon material mainly containing pores of a size less thanincludes treatment of the material in liquid oxidizers and heat treatment in a non-oxidizing atmosphere, wherein the first conducting processing in liquid oxidizers, and then heat treatment of the material at 300-800oC.

2. The method according to p. 1, characterized in that the cycle of oxidation - heat treatment is repeated until reaching the desired size and pore volume.

3. The method according to p. 1, characterized in that at the stage of oxidation of the carbon material as a liquid oxidizing agent, nitric acid concentration of 30-65%.

4. The method according to any of paragraphs. 1-3, characterized in that the treatment is carried out before formation of the functional groups on the surface of the carbon material is not less than 1.0 mmol/g

5. The method according to any of paragraphs. 1-4, characterized in that before heat treatment the material washed from the liquid oxidizer.

 

Same patents:

The invention relates to the technology of hydro-mechanical processing of porous carbon material with a view to its subsequent use for hemo - and enterosorption
The invention relates to the production of active carbon and organic products from carbonaceous raw materials and can be used in the woodworking industry for recycling wood waste

The invention relates to a method of continuous thermo-mechanical processing of carbon-containing raw material and installation for its implementation and can be used in the manufacture of carbons of the carbon-containing raw materials
The invention relates to the technology of activated carbon used for water purification, chemical-pharmaceutical, waste water and various fluids and liquids from solids organic substances

The invention relates to the production of active carbon and organic products from carbonaceous feedstock

The invention relates to the field of adsorption technique and can be used in the synthesis of activated carbons with high kinetic properties and high mechanical strength at water purification from harmful substances and the recovery of precious metals from solutions and slurries
The invention relates to the production of active carbons and can be used in various preadsorption processes: purification of alcoholic beverages, drinking water, pharmaceutical and food industries, as well as for the recovery of volatile solvents

The invention relates to carbon fiber materials and can be used in hydrometallurgy, electroplating industry, chemical and electrochemical processing of metals for the recovery of precious, rare and non-ferrous metals

The invention relates to an adsorption technique and can be used for the regeneration of activated carbons

FIELD: production of charcoal-fibrous adsorbents.

SUBSTANCE: the invention is dealt with the field of production of charcoal-fibrous adsorbents, in particular, with devices of charcoal-fibrous materials activation. The installation contains a vertical furnace for activation of a carbon fabric and a conjugated with it steam generator, which are connected to the power source and a control unit. And at the furnace output there is a reception device. At that the furnace contains a through heated muffle, through which the treated charcoal-fibrous fabric is continuously passing. At that the muffle is located inside the detachable heat-insulating furnace body, on the inner side of which there are heating elements. Besides at the furnace outlet there is a movable container with water, in which the lower end of the through muffle is dipped. The invention offers an installation for production of activated charcoal-fibrous material, which ensures a continuous process of treatment of the charcoal-fibrous material with an overheated steam and formation of the activated fabric with high mechanical properties and a cellular structure, simple in assembly and reliable in operation.

EFFECT: the invention ensures production of the activated fabric with high mechanical properties and a cellular structure, simple in assembly and reliable in operation.

8 cl, 4 dwg

FIELD: sorption technique for purification of industrial emissions and individual pipe security facilities.

SUBSTANCE: method for production of sorbent catalyst includes preparation of impregnating solution by introducing ammonium carbonate and copper and chromium compounds into ammonia water in ratio ammonia water/ammonium carbonate/copper basic carbonate/chrome anhydride of 1:(0.07-0.15):(0.03-0.06):(0.02-0.04); impregnation with metal-containing carbon solution; aging; and granule thermal treatment.

EFFECT: sorbent catalyst with prolonged protective action in relation to chlorocyanide and decreased cost.

4 cl, 3 ex

FIELD: sorption technology; cleaning waste industrial gases; individual protective means (gas masks and respirators).

SUBSTANCE: proposed method includes carbonization, activation and impregnation of warp with ammonia solution containing catalytic additives of copper, chromium, silver and triethylenediamine followed by removal of excess of solution, aging, heat treatment and cooling; used as warp is non-woven viscose material which is carbonized at temperature of 340-400°C and impregnated at volume ratio of non-woven material and impregnating solution of 1 : (14-18); excessive impregnating solution is removed by squeezing to ratio of material and solution of 1 : (4-5); after heat treatment, product is cooled at rate of (1.5-4)°C; concentration of catalytic additives in solution is as follows, mass-%: copper, 0.3-0.4; chromium, 0.12-0.16; silver, 0.01-0.02 and triethylenediamine, 0.05-0.08.

EFFECT: improved sorption ability by decane at retained adsorption ability by chlorocyanogen; reduced resistance of layer.

2 cl, 3 ex

FIELD: production of activated carbon for medicine, production of drugs and high-purity agents; thorough cleaning of gaseous and liquid media from low-molecular, medium-molecular and high-molecular admixtures.

SUBSTANCE: proposed method includes mixing of thermoreactive organic liquids and hardening catalyst, forming spherical granules at viscosity of 10-30 cSt heated to 90-120°C, hardening of spherical granules and separation of them from oil, carbonization and vapor-and-gas activation of granules and their screening-out. Time of presence of spherical granules in heated oil during which they undergo gelatinization and poly-condensation stages is 10-30 s, after which spherical granules are kept under layer of oil for 2-10 h till complete hardening. Carbonization is performed in carbon dioxide medium at temperature of 650-850°C at rate of 6-10°C/min. Vapor-and-gas activation is performed at temperature of 850-950°C. Proposed method makes it possible to control parameters of activated carbon of micro-, meso- and macro-structure.

EFFECT: possibility of producing activated carbon possessing high adsorption ability to admixtures containing gaseous and liquid media.

4 cl, 3 ex

FIELD: heat treatment of solid carbon-containing materials for production of activated carbon.

SUBSTANCE: proposed method includes heating and carbonization of raw material in horizontal rotary furnace at continuous mode for 1.0-3.0 h at temperature of 650-850°C and rate of heating not exceeding 10°C/min; method includes also delivery of formed carbonisate to vertical activation furnace by batches without cooling them; activation of each batch is continued for ≤30 min at temperature of 750-950°C in mode of layer suspended by jet of gaseous activating agent; new batch of carbonisate is delivered after unloading the batch of finished product; proposed method includes also delivery of vapor-and-gas mixture from activation furnace to carbonization furnace in counter-flow of material being carbonized, directing the vapor-and-gas mixture from carbonization furnace to waste-heat boiler for after-burning, generation of low-pressure steam required for preparation of activating agent and decontamination of flue gases formed in waste-heat boiler.

EFFECT: intensification of heat-exchange process; improved quality of activated carbon; improved economical parameters due to saving of fuel; reduction of technological process duration.

5 cl, 1 dwg, 2 tbl, 4 ex

FIELD: carbon materials.

SUBSTANCE: preparation of carbon material from organic raw material comprises carbonization of raw material in non-oxidative medium and activation by oxygen-containing agents at 750-900°C, said raw material being sapropel with content of organic substance 55-98%. Raw material is preliminarily cooled to 0-(-50)°C and carbonization is carried out at 300-700°C until summary pore volume 0.3-2.5 cm3/g and average macropore radius 100 to 5000 nm are obtained at following size distribution of pore radius: 60-80% above 100 nm, 15-30% 2-100 nm, and 1-10% below 2 nm based on total pore volume. Carbonized product is activated to give following size distribution: 50-75% above 100 nm, 20-40% 2-100 nm, and 1-15% below 2 nm. Material having mainly macroporous structure can be used as carrier in preparation of various-type catalysts and as matrix in preparation of deposited sorbents.

EFFECT: optimized preparation process conditions.

1 tbl, 18 ex

FIELD: carbon materials and medicine-destination sorbents.

SUBSTANCE: mobile granulated carbon black bed having specific surface 35-80 m2/g id heated to 700-900°C and then subjected to pyrolytic compaction accomplished by feeding gaseous and vaporous hydrocarbons into carbon black bed and two-step deposition of pyrolytic carbon layer on carbon black particles. Carbon black is first compacted to achieve loose density of granules 0.45-0.65 g/cm3 followed by isolation of granule fraction 0.50-1.20 mm in diameter, after which moving material bed is activated with water steam at bed temperature 800-900°C to achieve total pore volume in product 0.3-0.5 cm3/g.

EFFECT: achieved size uniformity of granules and reduced content of dust inside pores and on the surface of granules.

3 cl, 2 ex

FIELD: chemical technology, sorbents.

SUBSTANCE: invention relates to sorption technique. Invention proposes a method for preparing a chemosorbent involving preparing an impregnating solution containing ferric (III) chloride, impregnation of activated carbon grains with this solution followed by their thermal treatment. Impregnation is carried out in the ratio carbon mass to volume of impregnating solution from 1:0.66 to 1:0.9 and thermal treatment is carried out at 100-109°C. The content of ferric chloride in the ready product is 3.5-6.5 % by mass. Proposed method provides preparing sorbent with high absorptive capacity by mercury vapors. Invention can be used for removal of toxic substances from air and for solution of broad spectrum of ecology problems.

EFFECT: improved preparing method of chemosorbent.

2 cl, 3 ex

FIELD: carbon materials.

SUBSTANCE: invention provides a three-step method for modifying industrial activated carbon. In the first step, activated carbon is treated for 12 -24 h with ε-caprolactam aqueous solution under static conditions. Then, activated carbon is filtered, dried, and heated at 250°C in air atmosphere. Finally, it is subjected to carbonization by heating to 900°C in inert gas (argon or nitrogen) flow.

EFFECT: increased sorption capacity relative to organic compounds and heavy metal ions.

2 tbl, 2 ex

FIELD: production of the semi-coke; methods and devices for production of the semi-coke.

SUBSTANCE: the invention is pertaining to production of the semi-coke and may be used in production of the semi-coke. The method of production of semi-coke provides for air feeding air supply into the shaft furnace from the both sides of the coal layer, kindling of the coal and withdrawal of the flammable gas in the coal layer middle cross-section. The device for realization of the method is made in the form of the vertical apparatus of the shaft type, divided into two halves and containing two working chambers: the upper chamber and the lower chamber with provision of a capability of the air blowing from above and from below and withdrawal of the flammable gas in the middle cross-section of the layer. The invention ensures the increased productivity.

EFFECT: the invention ensures the increased productivity.

2 cl, 1 dwg, 1 ex

Up!