Method of the selective manufacture of the ordered carbonic nanotubes in the boiling bed

FIELD: chemical industry; methods of manufacture of the composites, catalytic agents, the materials for the gases storing.

SUBSTANCE: the invention is pertaining to the method of the selective manufacture of the ordered carbonic nanotubes in the boiling layer and may be used at the composites, catalytic agents, the materials for the gases storing. First manufacture the catalytic agent by deposition of the transition metal particles on the grains of the carrier in the "boiling bed" in the deposition reactor at the temperature of 200-300°C. The particles of the metal have the average size of 1-10 nanometers metered after the action of the temperature of 750°C. The grains of the catalytic agent contain 1-5 % of the mass particles of the metal. Fragments of metal also have the average size of 10-1000 μ. The carrier has the specific surface above 10 m2/g and is selected from the activated charcoal, silica, silicate, magnesium oxide or titanium oxide, zirconium oxide, zeolite oxide or the mixture of the grains of several of these materials. The ordered carbonic nanotubes are manufactured by decomposition of the gaseous source of carbon, for example, hydrocarbon, at its contact with at least of one solid catalytic agent. The decomposition is conducted in the "boiling" bed of the catalytic agent in the growth reactor at the temperature of 600-800°C. The invention allows to increase the output of the pure nanotubes with in advance calculated sizes.

EFFECT: the invention allows to increase the output of the pure nanotubes with in advance calculated sizes.

31 cl, 5 dwg, 3 tbl, 15 ex

 

The invention relates to the fabrication of ordered carbon nanotubes in the "boiling" layer.

Ordered carbon nanotubes in the light of the present invention are tubular structure with a diameter of between 0.4 nm and 50 nm and a length greater than the diameter of 100 times, in particular in 1000-100000 time. They can be represented or associated with particles of the metal catalyst, or isolated from these particles.

Carbon nanotubes have been described already (S.Iijima "Spiral nanotubes from graphite carbon. Nature, 354, 56, 1991), however, they are not subject to exploitation on an industrial scale. They could be, however, subject to numerous applications and, in particular, to be very useful and advantageous in the manufacture of composites, flat screens, gunners for atomic microscopes, during storage of hydrogen or other gas, as catalytic media.

The US patents No. 4663230 and US No. 5500200 describe how a catalytic obtain fibers of carbon by decomposition at high temperature gaseous carbon in contact with a solid catalyst containing particles of the transition metal with the size from 3.5 nm to 70 nm, at least on a granular solid carrier with a particle size of at least 400 μm

According to these sources of fiber include CE is dechnik from less ordered carbon surrounded by the outer zone of the ordered carbon, and have a diameter varying between 3.5 nm and 70 nm.

In US patent No. 5500200 indicates that the method of obtaining these fibers can be made in the "boiling" layer, but no presents, no examples of such a method of obtaining. All the examples carried out in a fixed bed with obtaining a mediocre performance against the carbon source (<20 wt%), and the real characteristics of the products obtained are not given.

These sources do not contain, therefore, no information regarding the receipt of ordered carbon nanotubes and/or use "boiling" layer for the manufacture of such nanotubes.

Other sources inform about the production of carbon nanotubes using catalytic composition containing metal particles in granular media, placed in a crucible (WO 00/17102)or introduced in the form of aerosol (WO 99/06618) in a reactor equipped with a source of carbon in gaseous form, such as carbon monoxide or ethylene. Performance (the number of the obtained nanotubes with respect to carbon source such methods is very low, resulting in a certain amount or pyrolytic amorphous carbon.

Thus, for practical industrial applications of carbon nano is logging it is important to simultaneously hold the calculated characteristics, performance and purity of the obtained product.

In WO 01/94260, publ. December 13, 2001, describes a method and apparatus for producing carbon nanotubes in several stages, in which the pre-processing stage catalyst can be used for removal of air discharged at the stage of preparation of the catalyst. In this way, as it is necessary to remove amorphous carbon formed in the reaction is not selective with respect to obtaining nanotubes.

US No. 4650657 and US No. 4767737 describe a method of obtaining a fibrous carbonaceous material with ferrous iron in the "boiling" layer by decomposition of carbon monoxide in the presence of hydrogen and a neutral gas, such as nitrogen, powder metal catalyst is ferrous iron in the presence of abrasive materials such as alumina, which can perform the function of the media.

These sources show that this "boiling" layer is designed to remove carbon formed on the surface of grains, to improve the dissolution and growth reduction reaction mass "boiling" layer.

However, these sources do not describe the method applicable for the production of carbon nanotubes. On the contrary, the obtained products are carbon particles of average size from 1 μ to 50 μm (table 1 US No. 4650657).

In the publication "Education is Finance nanotubes from catalytic iron carbon", Kharadi and others, Carbon, 34, No. 10 (1996), 1249-1257, the described method of producing carbon nanotubes on different catalysts in a fixed bed or in the reactor, called "boiling layer", with a diameter of 6.4 mm, However, this diameter can not provide this "boiling" layer. The catalysts were prepared by impregnation. This method is limited to use at a laboratory scale, produces amorphous carbon, and the characteristic use of such a "fluidized bed" would be less suitable than the sign of the fixed layer.

The patent FR No. 2707526 describes a method of producing the catalyst by chemical deposition in the vapor environment of the metal particles with a size of at least 2 nm in the "boiling" layer on the porous carrier particles at a temperature of less than 200°Setat patent describes, in particular, obtaining a rhodium catalyst and describes a catalyst adapted for the production of carbon nanotubes.

Thus, the invention aims to propose a method for selective receipt of ordered carbon nanotubes homogeneous medium size (a little different from the average) in terms that are compatible with use on an industrial scale, especially with increased performance in relation to the source of carbon, catalytic activity, the value of the product and the purity of the obtained p is oduct.

The invention relates to such a method in which the characteristics of the obtained nanotubes may be provided and adjusted by simply changing the parameters of the method.

The invention has in view, in particular, such a method, the performance of which is superior or equal to 80 wt%. (the number of the obtained nanotubes with respect to the carbon source).

The invention also provides granular catalyst composition which can be used in the method of obtaining an ordered carbon nanotubes, as well as the method of obtaining this catalytic composition.

(Throughout the text, all terms and signs related to the characteristics of "boiling" layer, taken from the reference "Fluidization Engineering", Kunii, D.; Levenspiel, O.; Butterworth-Heinemann Edition, 1991).

The invention relates to a method for selective receipt of ordered carbon nanotubes by decomposition of the carbon source in the gaseous state by bringing it into contact with at least a solid metal catalyst, comprising at least the transition metal on a solid granular media, these grain media containing metal particles called grains of catalyst, designed for education "boiling" layer, and the metal particles have an average size between 1 nm and 10 nm, measured after exposure to temperature of 750° With, in the way that the grain of the catalyst to form a "boiling" layer in the reactor, called reactor growth (growing) (30), it continuously releases the carbon source in contact with the grains of the catalyst in terms of providing "boiling" layer of catalyst, the reaction of decomposition and formation of nanotubes, characterized in that

- pre-get the catalyst by deposition of metal particles on grain media in the "boiling" layer, formed by the grains of the medium in the reactor, called a deposition reactor (20)containing at least the preceding component capable of forming metal particles and, thus, to obtain grains of catalyst containing 1%-5% of the weight. metal particles,

- then put the grains of catalyst in the reactor growth (growing) (30) without interaction with the external atmosphere and get it nanotubes in the "boiling" layer of catalyst.

Inventors was surprised that, despite instructions US No. 4650657 or US No. 4767737, the use of one "boiling" layer to obtain a catalyst(s), and other "boiling" layer to obtain nanotubes out of contact of the catalyst(s) with the atmosphere, in terms of the invention, not only leads to the decay of carbon-containing products formed on the catalyst, but, on the contrary, it enables selective images shall be ordered carbon nanotubes with a very homogeneous in size (a little different from the average size) and performance against the carbon more than 80% of the weight.

The catalyst is not exposed to any atmospheric pollution, and, in particular, is not oxidized during the period between its acquisition and usage in the reactor growth.

According to the invention the deposition reactor and the reactor growth (growing) mainly differ from each other. The deposition reactor and the reactor growth connect at least one sealed connection, and loaded into the reactor of grain growth of the catalyst through this connection. In another embodiment, it is possible to pick up and transfer the catalyst from the deposition reactor under inert atmosphere.

According to the invention mainly the catalyst was prepared by chemical deposition in the vapor environment.

According to another possible variant of the invention it is possible to use one and the same reactor as the deposition reactor and reactor growth. In other words, you can successfully make catalyst (precipitation), and then the fabrication of carbon nanotubes (growth) in the same reactor by changing the reactor inlet gas and reagents, as well as the operating parameters between the two stages.

According to the invention "boiling" layer of catalyst was prepared in a cylindrical reactor growth (growing) with the largest diameter of 2 cm and height of walls that can contain from 10 to 20 volumes of the initial fixed catalyst layer, a CR is the absence of the entire gas supply. This reactor allows you to get a real "boiling" layer.

Mostly get the "boiling" layer of catalyst in the mode of formation of bubbles, at least, substantially free from waste.

Moreover, mainly according to the invention to obtain the "boiling" layer of catalyst:

- form a layer of grains of the catalyst at the bottom of the reactor growth (grow),

- served in the growth reactor below the catalyst bed, at least a gas, the speed of which is greater than the minimum speed "boiling" layer of catalyst and less than the minimum rate of occurrence of the pressure mode.

Mainly for "boiling" layer of catalyst reactor supply growth under a layer of catalyst a gaseous source of carbon and at least a carrier neutral gas.

Further, according to the invention in a growth reactor serves at least carbon preceding component, forming a carbon source, at least the reaction gas and, at least, neutral gas, which are mixed prior to being fed into the reactor growth.

Under "reaction gas" means the gas, such as hydrogen, are able to participate and benefit receipt of nanotubes.

Mainly the carbon source contains at least carbon preceding component, selected from among coal is of Ogorodov. Among the hydrocarbons, which can be used, it is possible to produce ethylene and methane. In another embodiment, or in combination can be used however the oxide of carbon, especially carbon monoxide.

Mainly according to the invention the molar ratio of the reaction(s) strip(s) with carbon(their) predecessor(them) component(s) is greater than 0.5 and less than 10, namely, of order 3.

According to the invention in the growth reactor (30) provide a flow of carbon(General) previous(related) component(s) between 5% and 80%, namely about 25% of total gas consumption.

Mainly according to the invention "boiling" layer create at a temperature of 600°and 800°C.

The invention also extends to a catalytic composition designed for use in the method of receiving according to the invention.

The invention relates, therefore, the catalytic composition containing metal particles comprising at least a transition metal, and grain solid media, called grains of catalyst, characterized in that

grains of the catalyst is intended for education "boiling" layer

- the weight content of the metal particles is between 1% and 5%,

the average size of metal particles is between 1 nm and 10 nm, which is determined after heating at 750°C.

In usertext "average size" of particles or grains is an average value (the maximum of the distribution curve of the particle sizes and grain sizes of all particles or grains, certain traditional grading, namely, deposition rate to use. The term "size", used alone, means, for a given particle or the grain of their most real, the amount determined, for example, static measurements, due to the observation in the electron microscope scanning or transmission before use.

As the metal particles, the values of size or medium size, which are given throughout the text, measured before use in obtaining nanotubes, but after heating the catalytic composition at a temperature of 750°C.

It was found that the size of the particles to heat in General not available to the analysis, the particles are not visible in the microscope. This operation is carried out by contact with a neutral atmosphere such as helium and/or nitrogen at a temperature of 750°With, in a period of time which is sufficient to obtain stable values of the dimensions. This time is actually very small (of the order of minutes or several minutes). Activation can be carried out in the "boiling" layer ("boiling" layer of the grains of the catalyst prior to the filing of carbon) or a very different way, for example, in a fixed bed. In addition, the temperature of 750°should be considered only as a value for measuring the growth of the particles and does not match the value of the temperature needed is Oh for the method according to the invention or to obtain a catalytic composition according to the invention (even if this value can be advantageously used in certain ways of carrying out the invention). In other words, it only allows you to define the invention dimensional signs, but the catalytic composition, do not Mature at this precise temperature, may also correspond to the invention.

Mainly catalytic composition according to the invention is characterized by the fact that the average size of metal particles is between 2 nm and 8 nm, in particular of 4-5 nm, and the fact that, at least for 97% of the metal particles, the difference between their size and the average size of metal particles is less than or equal to 5 nm, in particular of the order of 3 nm.

Catalytic granular composition may contain a small amount of metal particles with a size of above average size (typically more than 200% of the average size). However, mainly according to the invention the size of the metal particles is less than 50 nm, and measured to the use and placement in the "boiling" layer and after activation at a temperature of 750°C.

Mainly according to the invention, metal particles are composed of at least 98 wt%, at least the transition metal and do not contain non-metallic elements other than with signs of carbon and/or oxygen and/or hydrogen and/or nitrogen. Can also be used in some other transition is diversified metals for placement on the carrier particles. Also can be used some other catalytic compositions in the form of a mixture. The catalyst may contain traces of impurities that may appear due to the method of producing metal particles. In addition to these traces (2%) the catalyst may contain one or more metal elements other than the transition metal. Preferably, according to the invention the metal particles are particles of pure metal, obtained by deposition, at least the transition metal.

According to the invention the weight content of the metal particles, in particular particles of iron is between 1.5% and 4%.

Mainly, according to the invention the catalyst particles have an average size between 10 μm and 1000 μm the Difference between the size of the catalyst particles and an average particle size of the catalyst is less than 50% of the value mentioned medium size.

It was found that these size distribution of metal particles and grains allow in frame "boiling" layer to obtain excellent results.

In addition, according to the invention using a carrier with a specific surface area exceeding 10 m2/, the Carrier is a porous material, the average pore size which is larger than the average size of metal particles. Mainly, the carrier is a material with sub-the internal pores, when the pores have an average size less than 50 nm. According to the invention, the carrier is selected from alumina (Al2About3), activated carbon, silica, silicate, magnesium oxide (MgO), titanium oxide (TiO2), Zirconia (ZrO2), zeolite or mixtures of several of these materials.

If the carbon source is ethylene, mainly according to the invention to use a catalyst containing metal particles of pure iron deposited in the dispersed state on a grain of alumina.

In the method of producing nanotubes according to the invention pre-receive grain of the catalyst by chemical deposition in the vapor environment of metal particles on grain media in "boiling" layer of the device, from at least the previous component that can form metal particles.

The invention also extends to a method for the catalytic composition according to the invention.

The invention relates, therefore, the method of producing a catalytic composition containing metal particles, at least a transition metal on a solid medium by vapour deposition environment of the metal particles on grain carrier, characterized in that exercise deposition, in particular, chemical vapour deposition environment of the metal particles on which the NRN media "boiling" layer of the device, from at least the previous component capable of forming metal particles, and those that choose a grain carrier and adjust the parameters of the deposition so that

grains of the catalyst was able to form a "boiling" layer

- the weight content of the metal particles is between 1% and 5%,

the average size of metal particles is between 1 nm and 10 nm, measured after heating at a temperature of 750°C.

Mainly, according to the invention, the deposition is carried out at a temperature between 200°300°C.

Preferably, the "boiling" layer media supply ORGANOMETALLIC previous component, namely Fe(CO)5.

Preceding the(s) component(s) in the vaporous medium is continuously added to the gas mixture, which provides reception "boiling" layer of grains of the media.

Thus, according to the invention "boiling" layer continuously supply the previous(and) component(s). Mainly gas mixture contains a neutral gas and at least the reaction gas. As the reaction gas use water vapor. Between 200°300°With water allows you to really spread out the previous component Fe(CO)5freeing the iron atoms. Avoid stages of calcination of the catalyst due to sintering of the metal particles is too large.

sabreena also concerns the method of producing nanotubes, catalytic composition and method for the catalytic composition that combines all or part of the characteristics mentioned above or below.

Other objectives, advantages and features of the invention will become apparent from the description and examples, illustrated in the enclosed drawings, in which

- figure 1 - scheme of the first installation to use the method of producing nanotubes according to the invention,

- figure 2 - scheme of the second installation option to obtain nanotubes according to the invention,

- figure 3 - histogram of the sizes of the metal particles of the catalytic composition according to the invention obtained in example 5

- 4 and 5 - Micrography nanotubes obtained according to the invention in example 9.

Figure 1 presents the scheme of the installation, ensure the use of the method of producing nanotubes according to the invention. This installation contains two reactors: reactor, called a deposition reactor (20), for the synthesis of catalyst and reactor, called reactor growth (growing) (30), to obtain nanotubes.

The deposition reactor (20) for the synthesis of catalyst chemical vapour deposition environment (CVD) contains glass sublimator (1), which introduced the ORGANOMETALLIC preceding component. This sublimator contains the Board for firing and can be hoveden to the desired temperature of the heated bath (2).

The source of neutral gas (3), for example helium, which involves a pair of used ORGANOMETALLIC element, is stored in the bottle and put in sublimator (1) using a flow regulator (not shown).

Sublimator (1) is connected with the supplied Board for firing glass bottom compartment (4), in which the introduced water vapor to enhance the decomposition of ORGANOMETALLIC preceding component. The presence of water produces a very active catalyst. This unit is a double membrane, temperature-controlled at a temperature which can be adjusted by means of a temperature controller (not shown). Water vapor affected by, and with a source of neutral gas (5), for example nitrogen, is stored in the bottle and served in the Department of (4) using a flow regulator (not shown). The flow of neutral gas (6), for example nitrogen, is designed to adjust spending in such a way as to be in the "boiling" layer. This gas (6) is stored in the bottle and served in the Department of (4) using a flow regulator (not shown).

The upper part of the compartment (4) sealed and connected to a glass column "boiling" (7) with a diameter of 5 cm, which is supplied at the base of the distributor strip. This column (7) with a double shell thermostated at a temperature which may be about is regulated by a temperature controller (8).

The upper part of the column (7) is connected to a vacuum pump (9) through an intermediate trap to hold liberated by decomposition of the gas.

Description examples concerning the preparation of catalysts by means of CVD, the following:

Mass Mathe preceding component introduced in sublimator (1).

Mass Msgrain media poured in column (7), and the mass of water Meintroduced into the compartment (4) using a syringe. The node formed by the compartment (4) and column (7), made vacuum. The temperature of the layer - T1.

Sublimator (1) refer to the temperature Tsand the pressure is xed at Pain General the device by entering the source gas 3, 5 and 6 (total flow rate Q). Deposition begins and lasts for time tc.

At the end of the deposition temperature to return to ambient temperature by slow cooling, and vacuum pump ostanavlivaites only system returned to ambient temperature and atmospheric pressure, the catalyst is removed from column (7) under the atmosphere of inert gas (e.g. nitrogen): system ready to use to obtain nanotubes.

In the examples were used two variants of the reactor growth (growing) (30) of different diameters to obtain nanotubes.

In the first version, presented in figure 1, the growth reactor consists of a column of Ki is amego" layer, made of quartz (diameter 2.5 cm) (10), provided in the middle of the distribution Board for firing (11), on which is placed the catalyst. Column (10) can be brought to the desired temperature by an external furnace (12)installed with possibility of vertical slip along the column "boiling" layer (10). When using the oven (12) has either a high position, where it heats not "boiling" layer, or a low position where it provides heating layer. Gas (13) (neutral gas, such as helium, carbon source and hydrogen) is stored in bottles and is entered in the column "boiling" layer with flow controls (14).

In the upper part of the column "boiling" layer (10) is hermetically coupled to the trap (15), designed to collect random fine catalyst particles or a mixture of catalyst and nanotube.

The height of the column (10) are made so as to maintain the "boiling" layer of catalyst. In particular it is at least 10 to 20 initial heights (fixed) catalyst layer, defined in the absence of gas supply and should conform to the heated zone. In the examples, select the column (10) with a total height of 70 cm, heated at 60 cm height oven (12).

In the second embodiment, the reactor growth (growing) consists of a column "boiling" layer, made of stainless steel (diameter 5 with the, with a total height of 1 m, is heated along its entire height), provided in the base distribution Board (stainless steel), which place the catalyst. The column may be brought to the desired temperature by means of two stationary furnace, and the temperature is controlled by a thermocouple immersed in the fluidized layer. Gas (neutral gas, a carbon source and hydrogen is stored in bottles and served in the column "boiling" layer with flow regulators.

Figure 2 represents a variant of the method according to the invention, in which the catalytic composition receive a continuous deposition reactor (20), is continuously removed from his pipe (25A), by which it is introduced into the intermediate buffer tank (26), from which the catalyst is continuously serves pipe (25B) in the growth reactor (30), where they receive nanotubes. From the tank, the deposition reactor (20) is continuously supplied with grains of the medium through the tube (19). The grain of the catalyst, which is attached nanotubes continuously discharged from the reactor growth (30) through the extraction tube (27), which leads to a buffer tank (28). Nanotubes can then be separated from the catalyst in a known manner and stored in the tank (29).

In the embodiments shown in figures, use the reactor growth (growing) (30)other than the deposition reactor (20). Another is ariante you can use the deposition reactor (20) for growth of nanotubes at a later stage. However, this last option allows you to successfully carry out both phases with different settings, and growth response in danger of being violated it is at its initial stage, the residual by-products of phase deposition.

Description of examples concerning the manufacture of nanotubes according to the invention, the following:

Mass Mwithcatalyst (catalytic composition according to the invention) is entered in column "boiling" layer (10) under the atmosphere of inert gas.

When the furnace (12) is in the lower position relative to the catalytic layer, its temperature is increased to the desired value of Tnfor the synthesis of nanotubes either under inert gas or under an atmosphere of a mixture of inert gas and hydrogen (reaction gas).

Once this temperature is reached, the source of carbon, hydrogen and neutral gas is injected into the column (10). The total flow Qtprovides the layer mode of bubbles at a temperature Tnwithout waste.

Immediately starts the growth of nanotubes, which lasts for time tn.

At the end of the growth furnace (12) is placed in a high position relative to the catalytic layer, the flow of the carbon source and hydrogen is stopped, and the temperature returns to ambient temperature by slow cooling.

In the case of a reactor with h the movable furnaces use the same.

Carbon nanotubes, United with the metal particles and attached to the carrier particles are then removed from the growth reactor (30) and stored without special precautions. These tubes can then be separated from the metal particles and the carrier particles by acid dissolution and stay in a clean condition, as described in WO 01/94260.

Deposited the amount of carbon was measured by weighing and by using thermal gravimetric analysis.

Made thus nanotubes were analyzed by electron microscopy in transmission (MET) and by electron microscopy in the scan (MEW) to measure growth and dispersion, and crystallography x-ray and Raman spectroscopy to assess the degree of crystallization of the nanotubes.

EXAMPLES

Obtaining catalysts

Comparative example 1

Prepare the catalyst from 2.6% Fe/Al2About3a known method of liquid impregnation with metal salts. The previous component of iron is a hydrate of iron nitrate Fe(NO3)3·9H2O. Grain carrier of alumina have high granularity 120, bulk density 1.19 g/cm3and a specific surface area of 155 m2/year Source gas is nitrogen.

The catalyst is prepared as follows.

The media is a mesoporous alumina. 100 g of this carrier vysushivaet for 120 minutes. The appropriate amount of salt to obtain 2,6% Fe/Al2About3lead in contact with the alumina at 250 cm3desarrollando ethyl alcohol. After 3 hours of contact, the solvent evaporated, and the catalyst was dried overnight under low pressure (0.1 Topp). The catalyst calcined at 500°C for 2 hours, then crushed under a mixture of nitrogen/hydrogen (80/20 by volume) for 2 hours at 650°C.

The resulting catalyst contains metal particles with an average size of 13 nm, and changing their sizes relative to this value is, at least for 98% of them a maximum of about 11 nm.

Example 2.

Prepare the catalyst from 2.6% Fe/Al2About3in accordance with the method according to the invention in the deposition reactor (20)as above, but without the use of water to activate the decomposition of the previous component. Used ORGANOMETALLIC preceding component is a complex of Fe(CO)5at that time, as the carrier and the gas used are the same as in example 1. Various parameters are adjusted as follows:

Ma=9,11 g,

Ms=100 g

T1=220°C

Pa=22 Topp,

Ts=35°C,

Q=82 cm3/min,

tc=15 minutes

The resulting product (catalytic composition according to the invention) is a metal particle, USAID is installed on grain media. The size of the metal particles after heating in nitrogen at 750°C for 5 minutes is equal to 4 nm, and changing their sizes relative to this value for at least 97% of them is a maximum of about 3.5 nm.

Example 3.

Prepare the catalyst with 1.3% Fe/Al2About3according to the invention. The source gas is nitrogen. ORGANOMETALLIC preceding component carrier and the gas are the same as in example 2. Various parameters are adjusted as follows:

Ma=7,12 g,

Ms=150 g,

Me=10 g,

T1=220°C

Pa=26 Topp,

Ts=35°C,

Q=82 cm3/min,

tc=7 minutes

The resulting product is a particle with an average size equal to 3 nm, and changing their sizes relative to this value, at least for 98% of them amounts to a maximum of about 2.5 nm.

Example 4.

This example shows obtaining a catalyst with 2.5% Fe/Al2About3. ORGANOMETALLIC preceding component, the media and gas - the same as in example 2. Various parameters are adjusted as follows:

Ma=17,95 g,

Ms=200 g,

Me=25 g,

T1=220°C

Pa=20 Topp,

Ts=35°C,

Q=82 cm3/min,

tc=18 minutes

The resulting product is a metal particle with an average size equal to 4 nm, and changing their sizes from which to oseney to this value, at least for 98% of them, is a maximum of about 3.5 nm.

Example 5.

This example shows the receiving catalyst from 3.5% Fe/Al2About3. Prior ORGANOMETALLIC component carrier and the gas are the same as in example 2. Various parameters are adjusted as follows:

Ma=12,27 g,

Ms=100 g

Me=25 g,

T1=220°C

Pa=24 Topp,

Ts=35°C

Q=82 cm3/min,

tc=20 minutes

The resulting product is a particle with an average size of 5 nm, and changing the size of metal particles with respect to this value, at least for 98% of them amounts to a maximum of about 4.5 nm. A histogram of the growth of particles is given in figure 3. In this figure, the average particle size is indicated on the abscissa axis and the number on the y axis.

Example 6.

This example shows the receipt of the catalyst 5,65% Fe/Al2About3. ORGANOMETALLIC preceding component carrier and the gas are the same as in example 2. Various parameters are adjusted as follows:

Ma=9,89 g,

Ms=100 g

Me=15 grams

T1=220°C

Pa=23 Topp,

Ts=35°C,

Q=82 cm3/min,

tc=23 minutes

The resulting product is a particle with an average size equal to 6 nm, and changing the size of metal particles with respect to et the th value, at least for 98% of them at the maximum is about 5.5 nm.

The results of examples 1-6 are summarized in the following table I.

Table I
Growth
ExamplePriorMethod%Femetal
componentparticles (nm)
1Fe(NO3)3·9H2Oimpregnation2,613±11
2Fe(CO)5CVD*2,64,5±4
3Fe(CO)5CVD1,33±2,5
4Fe(CO)5CVD2,54±3,5
5Fe(CO)5CVD3,505±4,5
6Fe(CO)5CVDthe 5.656±5,5
* Cooking without adding water.

Obtaining nanotubes.

Comparative example 7.

Make mone is ocenochnye nanotubes using the catalyst of example 1 from 2,6% Fe/Al 2About3. In this experiment the amount of catalyst was prudently reduced so that not to get a big waste, in order to better clarify the influence of the method of preparation of the catalyst. Various parameters are adjusted as follows:

Mc=5 g,

Tn=750°C

Qt=320 cm3/min,

The amount of injected carbon = 3 g

tn=60 minutes

In these conditions the mass of deposited carbon is 0.16 g, which is comparable with the result obtained in test 5 of example 12 (the same percentage of iron and identical conditions), i.e., 1,57, the layer Height remains the same as in test 5 of example 12, which is approximately 1 cm to 8.7 see the Analysis MEW and MET show that multi wall nanotubes are only a part of the final product, and that decapsulation particles are very numerous in this case. Thus, only the catalytic composition according to the invention allows selective production of nanotubes homogeneous medium size.

Example 8.

Produce multi wall nanotubes using the catalyst according to example 2 from 2.6% Fe/Al2About3obtained without the use of water to activate the decomposition of the previous component. In this experiment the amount of catalyst was prudently reduced so that not to get Bolshakov and to better clarify the effect of activation of the catalyst by water. Various parameters are adjusted as follows:

Mc=5 g,

Tn=750°C

Qt=320 cm3/min,

The amount of injected carbon = 3 g

tn=60 minutes

In these conditions the mass of deposited carbon is 0.88 g, which is comparable with the result obtained in test 5 of example 12 (the same percentage of iron and identical conditions except for the addition of water), components of 1.57 hacktivate catalyst water increases, thus, the performance output of the nanotubes.

Analyses MEW and MET show that multi wall nanotubes are the only reaction product deposition.

Example 9.

Make nanotubes using the catalyst according to example 4 with 2.5% Fe/Al2About3and ethylene using a reactor of stainless steel with an inner diameter of 5 cm Were carried out five tests in the same conditions to verify the reproducibility of the results.

Various parameters are adjusted as follows:

Mc=100 g

Tn=650°C

Qt=1200 cm3/min,

The amount of injected carbon = 30 g,

tn=120 minutes

In these conditions the mass of deposited carbon is 27±0.2 g in all tests conducted, i.e. the yield is 90% compared to widen the th carbon. Analyses MEW and MET show that multi wall nanotubes are the only reaction product. Pyrolytic carbon or metal encapsulated particles are noticeably absent in the sediment. Micromachine THE formed nanotubes are presented in figure 4 and 5.

Figure 4 scale, this solid line is 400 nm. Figure 5 it is 20 nm.

The outside diameter of the nanotubes is 20±5 nm and inner diameter of 4±2 nm, which corresponds to the average size of the metal particles. The DRX analyses and Raman received nanotubes show a good degree of graphitization of the latter; this can be seen in figure 5 where you can see the layers of graphite.

Example 10.

Make nanotubes using the catalyst according to example 4 with 2.5% Fe/Al2O3and ethylene using a reactor of stainless steel with an inner diameter of 5 cm

Various parameters are adjusted as follows:

Mc=100 g

Tn=650°C

Qt=1200 cm3/min,

The amount of injected carbon = 45 g,

tn=180 minutes

In these conditions the mass of deposited carbon is 44 g or exit 97% relative to the injected carbon. Analyses MEW and MET show that multi wall nanotubes are the only reaction product.

Example 11.

The test series was carried out in the reactor diameter is m 2.5 cm so to study the influence of the amount of metal to obtain multi wall nanotubes using catalysts according to examples 3-6 and catalyst with 0.5% iron, prepared in a similar manner, and ethylene as a carbon source. In these tests the amount of catalyst was reduced in such a way as not to get significant performance, in order to better clarify the effect of the amount of metal.

Various parameters are adjusted as follows:

Mc=5 g,

Tn=750°C,

Qt=320 cm3/min,

The amount of injected carbon = 3 g

tn=60 minutes

The test results 1-5 of this example is shown later in table II.

Table II
The layer height
Besiegedafter
Test%Fecarbon (g)depositionObservation (SO)
(cm)
Multi wall
1 0,50,523,2nanotubes
Multi wall
21,31,134nanotubes
Multi wall
32,51,906,2nanotubes
Multi wall
43,5to 2.298,6nanotubes
Nanotubes+
particles
5the 5.651,373kapsulirovannaja
iron

Analyses MEW and MET show that multi wall nanotubes are single or have a large proportion of the reaction product deposition. Pyrolytic carbon or particles kapsulirovannaja metal are absent in the tested the deposits 1-5. In test 1, the concentration of iron is low (0,5%), and productivity is low. In test 5 iron concentration is high, the growth of particles of iron are significant, and there is education kapsulirovannyh particles of iron.

Example 12.

The test series was carried out in a reactor with a diameter of 2.5 cm, in order to study the effect of temperature on obtaining multi wall nanotubes using the catalyst according to example 4 with 2.5% Fe/Al2O3and ethylene as a carbon source. In these tests the amount of catalyst was reduced to not get significant performance, in order to better clarify the effect of temperature.

Various parameters are adjusted as follows:

Mc=5 g,

Tn- ranges from 500 to 850°C

Qt=320 cm3/min,

The amount of injected carbon = 3 g

tn=60 minutes

The test results 1-6 of this example are summarized in table III.

Table III
Height
TestTemperatureBesiegedlayer afterObservations
(°)carbon (g)OS is born (cm) (THE)
Multi wall
15000,051,9nanotubes
Multi wall
26001,054,4nanotubes
Multi wall
36501,135,5nanotubes
Multi wall
47001,29the 4.7nanotubes
Multi wall
5750of 1.578,7nanotubes
Nanotubes+
pyrolytic
6850to 1.86the 4.7 carbon+particles
kapsulirovannaja
iron

Analyses MEW and MET show that multi wall nanotubes are single or have a large proportion of the reaction product deposition. Pyrolytic carbon or particles kapsulirovannaja metal in tests 1-5 are noticeably absent. In test 1, the temperature is too low, so that the reaction takes place properly. In test 6, the temperature is too high, thermal decomposition of ethylene leads to the formation of pyrolytic carbon.

Example 13.

This example shows the receipt of nanotubes using the catalyst according to example 4 with 2.5% Fe/Al2About3and ethylene in the reactor growth (growing) stainless steel with an inner diameter of 5 cm

Various parameters are adjusted as follows:

Mc=100 g

Tn=650°C

Qt=1405 cm3/min,

The amount of injected carbon = 48,5 g,

tn=120 minutes

In these conditions the mass of deposited carbon is equal to 46.2 g, i.e. the performance is 95% compared to the injected carbon. Analyses MEW and MET show that multi wall nanotubes are the only products the om response.

Example 14.

This example shows the receipt of nanotubes using the catalyst with 0.5% Fe/Al2O3prepared according to the method described in example 4, and ethylene using a reactor growth (growing) stainless steel with an inner diameter of 5 cm

Various parameters are adjusted as follows:

Mc=100 g

Tn=650°C

Qt=1405 cm3/min,

The amount of injected carbon = 48,5 g,

tn=120 minutes

In these conditions the mass of deposited carbon is equal to 20.4 g, i.e. the performance is 42% compared to the injected carbon. Analyses MEW and MET show that multi wall nanotubes are the only reaction product. This example confirms the poor performance of the catalyst with 0.5% iron.

Example 15.

This example illustrates the purification of the obtained nanotubes obtained using catalyst with 2.5% Fe/Al2About3and ethylene, using growth reactor of stainless steel with an inner diameter of 5 cm according to the method described in example 9. Solid powder emerging from the reactor is introduced into the cylinder 21 in the presence of 500 ml of water and 500 ml of 98% sulfuric acid.

Various parameters are adjusted as follows:

M (nanotubes + catalyst)=75 g,

V (H2O)=500 ml,

V (H2SO4, 98%)=500 ml,

T=140°C,/p>

tn=120 minutes

After two hours the reaction of dissolution of alumina acid solution is filtered, the nanotubes are washed in water several times and dried in the dryer. The dry product (thermogravimetric analysis) is 97% weight. carbon nanotubes and 3% iron.

1. Method for selective receipt of ordered carbon nanotubes by decomposition of gaseous carbon by contact with at least a solid catalyst containing at least the metal particles of the transition metal having an average size between 1 and 10 nm, measured after exposure to temperature of 750°and grain solid media, called grains of catalyst intended for education "boiling" layer, in which the "boiling" layer of catalyst is formed in the reactor, called reactor growth (growing) (30), and continuous introduction of carbon in the growth reactor (30) to contact with the catalyst particles under conditions providing the "boiling" layer of catalyst and the reaction of the decomposition and the formation of nanotubes, wherein the pre-prepare the catalyst by deposition of metal particles on grain media in "boiling" layer of the device obtained in the reactor, called a deposition reactor (20)with at least the previous component capable of forming a metal cha is based, and thus to obtain a catalyst containing metal particles in a weight amount between 1 and 5%, then put the catalyst in the reactor growth (growing) (30) without contact with the external atmosphere and provide the receipt of nanotubes in the "boiling" layer of catalyst in the reactor growth (growing) (30).

2. The method according to claim 1, characterized in that the prepared catalyst with an average size of metal particles is from 2 to 8 nm, in which at least 97% of them the difference between their size and the average size of metal particles is less than or equal to 5 nm.

3. The method according to claim 2, characterized in that the prepared catalyst with an average particle size of from 4 to 5 nm, and in which 97% of the number of metal particles have a difference between their size and the average size of metal particles of about 3 nm.

4. The method according to claim 1, wherein preparing the catalyst metal particles with size less than 50 nm.

5. The method according to claim 1, characterized in that the "boiling" layer placed in a reactor growth (growing) (30) at a temperature between 600 and 800°C.

6. The method according to claim 1, characterized in that the metal particles are composed of at least 98 wt.%, at least the transition metal and do not contain non-metallic elements other than traces of carbon and/or oxygen and/or hydrogen and/or nitrogen.

7. The method according to claim 6, characterized in that h is of metal particles obtained by the deposition of pure metal, at least the transition metal.

8. The method according to claim 1, characterized in that the grains of the catalyst made with the average size of concluded between 10 and 1000 microns.

9. The method of claim 8, wherein the difference between the grain size of the catalyst and medium size made of grains of catalyst below 50% of the value above medium size.

10. The method according to claim 1, characterized in that use a carrier with a specific surface area greater than 10 m2/year

11. The method according to claim 1, characterized in that the carrier is a porous material, the average pore size which is above the average size of the metal particles.

12. The method according to claim 1, characterized in that the medium is selected from among alumina, activated carbon, silica, silicate, magnesium oxide, titanium dioxide, zircon, zeolite, or a mixture of grains of several of these materials.

13. The method according to claim 1, characterized in that the metal particles consist of pure iron, precipitated in a dispersed state on the alumina grains.

14. The method according to claim 1, characterized in that the deposition reactor (20) and the reactor growth (growing) (30) different.

15. The method according to 14, characterized in that the deposition reactor (20) connected to the reactor growth (growing) (30) by at least a sealed tube (25A, 26, 25b) and the reactor growth (growing) (30) is provided with a grain of catalysis of the ora through this tube (25).

16. The method according to claim 1, characterized in that the catalyst was prepared by chemical deposition in the environment of a pair of metal particles on grain media's "boiling" layer in the deposition reactor (20).

17. The method according to item 16, characterized in that the deposition of metal particles on a carrier is carried out at a temperature between 200 and 300°C.

18. The method according to 17, characterized in that the supply of "boiling" layer of the carrier particles in the deposition reactor (20), at least ORGANOMETALLIC previous component.

19. The method according to p, characterized in that as the previous component using Fe(CO)5.

20. The method according to item 16, characterized in that the preceding(s) component(s) in the form of vapour is continuously added to the gaseous mixture is continuously fed into the deposition reactor (20) in a "boiling" layer of the device.

21. The method according to claim 20, characterized in that the gas mixture contains a neutral gas and at least the reaction gas.

22. The method according to item 21, characterized in that the reaction gas use water vapor.

23. The method according to item 16, wherein preparing the "boiling" layer of catalyst in a cylindrical reactor growth (growing) (30) with the largest diameter of 2 cm and a height of the walls that can contain from 10 to 20 volumes of the initial fixed catalyst layer, such that determined in the absence of any gas supply.

24. The method according to item 23, wherein receiving the "boiling" layer of catalyst in the reactor growth (growing) (30) using bubbles, substantially free from waste.

25. The method according to paragraph 24, characterized in that to obtain the "boiling" layer of catalyst in the reactor growth (growing) (30): form a layer of catalyst on the reactor bottom growth (growing) (30), pass in the reactor growth (growing) (30) under a layer of catalyst, at least a gas, the speed of which exceeds the minimum rate of "boiling" of the catalyst particles, and below the minimum rate of appearance mode of the ash.

26. The method according A.25, characterized in that to obtain the "boiling" layer of catalyst in the growth reactor (30) under grain of catalyst injected gaseous source of carbon and at least neutral gas.

27. The method according to p, characterized in that the supply reactor growth, at least carbonaceous previous component, forming a carbon source, at least the reactive gas and at least a neutral gas, which are mixed before introduction into the reactor (30).

28. The method according to item 27, wherein the carbon source contains at least carbon-containing element selected from among hydrocarbons.

29. The method according to item 27, wherein as a reaction gas to the reactor growth supply hydrogen.

30. The method according to clause 29, wherein the molar ratio of the reaction(data) strip(s) to carbon(current) previous(current) component(s) is greater than 0.5 and less than 10, preferably about 3.

31. The method according to item 30, wherein ensure reactor growth (growing) (30) the receipt of carbonaceous(General) previous(related) component(s)of between 5 and 80%, in particular about 25% of the total amount of gas.



 

Same patents:

FIELD: chemical industry; production of fullerenes and other carbonic nanomaterials.

SUBSTANCE: the invention is pertaining to the method of production of fullerenes and other carbonic nanomaterials. The process provides for incineration of the polynuclear aromatic hydrocarbon fuel, which contains the component being the aromatic molecule containing two or three six-membered kernels, two either three five-membered kernels or one six-membered kernel and one five-membered kernel; and withdrawal of the condensable products produced at incineration of the polynuclear aromatic hydrocarbon fuel. The polynuclear aromatic hydrocarbon fuels contain the polycyclic aromatic hydrocarbons, which include the significant amount of indene, methylnaphthalenes or their mixtures. The technical result of the invention is improvement of the synthesis of fullerenes and carbonic nanomaterials, possibility to use the cheap hydrocarbon fuel (for example - the fractions of the oil distillate and the tar distillate), the increased degree of the carbon fractional conversion.

EFFECT: the invention ensures the improved process of the synthesis of the fullerenes and the carbonic nanomaterials, the opportunity to use the cheap hydrocarbon fuel - the fractions of the oil distillate and the tar distillate, the increased degree of the carbon fractional conversion.

33 cl, 1 ex, 2 tbl

FIELD: chemical industry; other industries; devices for production of the solid-phase nanostructured materials.

SUBSTANCE: the invention is pertaining to the nanotechnologies and may be used at production of the carbonic nanotubes. The invention provides, that in the steam generator (4) they prepare multiphase mixture of the initial substance and route it under pressure to the gasodynamic resonator (9), where the mixture detonates. The products of the detonation combustion through the nozzle (2) are fed in the chamber (3), extended and cooled forming clusters. The produced clusters are routed onto the target (12) with the formation die (1) arranged in the chamber (3). The substrate (11) of the target (12) is supplied with the temperature control device providing the cyclical heating and cooling. The formation and growth of the solid-phase nanostructured materials takes place on the formation die (1). As the pressure in the gasodynamic resonator (9) drops, the feeding of the multiphase mixture in it is restarts and the process repeats. The invention allows to provide the optimal conditions of the growth of the nanostructured materials and due to it to increased efficiency of the process.

EFFECT: the invention ensures provision of the optimal conditions for the growth of the nanostructured materials and the increased efficiency of the process.

1 dwg

FIELD: chemical industry; methods of the chromatographic concentration of the fullerenes.

SUBSTANCE: the invention is pertaining to the field of the chemical industry. The mixture of the fullerenes dissolved in the organic solvent is gated through the column with the carbon-containing sorbent. At that as the sorbent they use the ground gray iron. After saturation of the ground gray iron with the mixture of the fullerenes they first eluate the fullerenes (С60 and С70) with o- xylene; then eluate the higher fullerenes (С76 and further) with 0- dichlorobenzene into the separate enriched by them fraction. The invention ensures the increased output of the higher fullerenes extracted into the enriched by them fraction and may be easily realized, since it is based on the usage of the accessible product - gray-iron and the dissolvents traditionally used in the fullerenes production process.

EFFECT: the invention ensures the increased output of the higher fullerenes, simplicity of the method realization, usage of the accessible product-gray-iron and the dissolvents traditionally used in the fullerenes production process.

2 tbl, 2 ex

FIELD: hydrogen production processes.

SUBSTANCE: invention relates to catalytic processes of hydrogen production from hydrocarbon-containing gases. Method of invention comprises elevated-pressure catalytic decomposition of methane and/or natural gas into hydrogen and carbon followed by gasification of the latter with the aid of gasification reagent in several in parallel installed interconnected reactors, each of them accommodating preliminarily reduced catalyst bed. When one of reactors is run in methane and/or natural gas decomposition mode, the other gasifies carbon, the both operation modes being regularly switched. Operation period in one of the modes ranges from 0.5 to 10 h. Carbon gasification reagent is, in particular, carbon dioxide and catalyst utilized is reduced ferromagnetic thermally stabilized product consisting of iron oxides (30-80 wt %) and aluminum, silicon, magnesium, and titanium oxides. Methane and/or natural gas is decomposed at 625-1000°C and overpressure 1 to 40 atm.

EFFECT: ensured environmental safety and increased productivity of process.

3 cl, 1 dwg, 8 ex

FIELD: electronic-vacuum engineering.

SUBSTANCE: invention is intended for implementation in manufacture of light sources, indicator lamps, and optic displays. Graphite heater is placed in working volume, into which nitrogen or nitrogen/argon blend (ratio from 1:10 to 1:1) is pumped in at pressure up to 15 MPa and removed. These operations are repeated threefold. Thereafter, above-indicated gas or gas blend is pumped in at pressure 10 to 90 MPa and working volume is heated to 2100-2200 K at velocity 1 to 100 K/min and aged for 10 min to 4 h. Temperature is the lowered to ambient value and then pressure is reduced to atmospheric value at velocity 1 MPa/sec. Resultant nitrogen-carbon nanofibers are withdrawn from working volume, dispersed in ethyl alcohol by means of ultrasonic disperser giving power 180-200 W for 5-15 min, filtered, and applied onto cathodic plate.

EFFECT: enabled manufacture of various-structure nanofibers in large amounts by easy and economic way.

3 cl, 6 dwg, 1 tbl, 7 ex

FIELD: chemical industry; steel industry; methods of production of the carbonic granulated material used for the steel alloying and the material produced by this method.

SUBSTANCE: the invention is pertaining to the carbonic materials and their production, mainly to the carbonic granulated materials and the methods of their production. The method of production of the carbonic granulated material for alloying the steel provides for heating of the layer of the granulated carbon black in reaction zone of the rotated horizontal reactor up to 800-1200°C, feeding in the moving hydrocarbon black layer of the gaseous or vaporous hydrocarbons with subsequent their thermal decomposition and the pyrocarbon settling-down on hydrocarbon black. Feeding of the hydrocarbons in the layer of the hydrocarbon black with the specific surface of 5-120 m2/g and with adsorption of dibutylphthalate of 30-160 ml/100g is conducted with the volumetric speed of 18-34 hour-1 " 1 at the ratio of the height the hydrocarbon black layer to the diameter of the reaction zone as 0.2-0.4. The carbonic material for alloying the steel produced by the offered method, possesses the value of the closed porosity of the compacted pyrocarbon granules of the hydrocarbon black equal to 33-58 %. The technical result of the invention is production of the carbonic material with the properties ensuring upgrading of the degree of absorption of the carbonic material in the process of the out-of-furnace treatment of the steel in combination with the high accuracy of the alloying the steel with the carbon (± 0.02 %).

EFFECT: the invention ensures production of the carbonic material with the properties providing upgrading of the degree of absorption of the carbonic material in the process of the out-of-furnace treatment of the steel in combination with the high accuracy of the alloying the steel with the carbon.

3 cl, 3 ex, 1 tbl

FIELD: hydrocarbon conversion processes.

SUBSTANCE: process consists in catalytic decomposition of hydrocarbon-containing gas at elevated temperature and pressure 1 to 40 atm, catalyst being reduced ferromagnetic cured product isolated by magnetic separation from ashes produced in coal combustion process at power stations. The catalytic product represents spinel-type product containing 18 to 90% iron oxides with balancing amounts of aluminum, magnesium, titanium, and silicon oxides. Prior to be used, catalyst is subjected to hydrodynamic and granulometric classification.

EFFECT: reduced total expenses due to use of substantially inexpensive catalyst capable of being repetitively used after regeneration, which does not deteriorate properties of original product.

2 cl, 6 ex

FIELD: medicine and perfume industry; methods of production of fullerene-containing emulsions.

SUBSTANCE: the invention is pertaining to the field of medicine and perfume industry, in particular, to the method of production of fullerene-containing emulsion and may be used at manufacture of the cosmetic and medical products for the oral external application. The fullerene solution in the organic solvent blend with water, preferably, in the volumetric ratio of 1 : (1-3). Search for the resonance frequency of the ultrasonic emission ensuring origination of the resonance state in the system: the ultrasonic emitter - the volume of the indicated mixture. The indicated mixture is subjected to action of the ultrasonic radiation of the found frequency for no less than 5 minutes at the temperature of 40-50°C. Then add cholesterine or sodium dodecylsulfate in the concentration of 2-10 mg/ml. The treatment with the ultrasonic emission is repeated during 5-20 seconds. It is possible to use the ultrasonic emission with the sinusoidal, rectangular, saw-tooth forms of pulses. Use the organic solvent containing the non-saturated carboxylic acid, for example: oleic acid, linoleic acid, linolenic acid, arachidonic acid or their mixture; sea-buckthorn oil, cedar oil, linseed oil, luccu oil or their mixture; fish fat, animal fat or their mixture; lemon, orange, cypress, eucalyptus essential oils, turpentine oil, camphor oil or their mixture. The method is simple, allows: to produce the stable within no less than 3 months emulsions. which are not stratifying at the room temperature; to expand the spectrum of the produced nontoxic effective solvents.

EFFECT: the invention presents the simple method ensuring production of the stable within no less than 3 months non-stratifying at the room temperature emulsions and expansion of the spectrum of the produced nontoxic effective solvents.

13 cl, 5 dwg, 26 ex

FIELD: carbon materials.

SUBSTANCE: invention can be used in manufacture of cosmetics, therapeutical agents, and other biologically active preparations. Fullerene is mixed with organic solvent to achieved homogenous mass. Resonance frequency of ultrasonic emission providing appearance of resonance state in system ultrasonic emitter-above prepared mixture is found. The mixture is then affected by ultrasonic emission at thus found frequency for at least 15 min at 40-70°C. Ultrasonic emissions with sinusoidal, rectangular, sawtooth pulse forms are suitable. Organic solvent is selected from those containing unsaturated carboxylic acid, e.g. oleic, linoleic, linolenic, arachidonic acid, or mixture thereof; sea-buckthorn oil, cedar oil, linseed oil, olive oil, or mixture thereof; cod-liver oil, animal fat, or mixture thereof; citric, orange, cypress essential oils, turpentine oil, camphor oil, or mixture thereof.

EFFECT: simplified fullerene dissolution procedure and extended range of nontoxic effective solvents compatible with biological structures.

10 cl, 5 dwg, 1 tbl, 24 ex

FIELD: carbon materials.

SUBSTANCE: object of invention are carbon materials, in particular fullerenes and pyrolytic carbon, which can be used in manufacture of liquid media-treatment sorbents. Initial carbon-containing substance, e.g. graphite, is introduced into reaction zone, exposed to high-temperature field, sublimed, and subjected to phase transformation. Processing product is discharged in flow of inert gas, preliminarily used for flushing peripheral part of the chamber reaction zone, in the form of expanding torch with its lesser summit adjoining space of the chamber. Expansion of flow is made in downstream direction. First, additional volume of inert gas is introduced into flow tangentially to circumference of its cross-section and at an angle to its axis. Then, central portion of the flow is split and simultaneously compressed and further subjected to dilatation to form vortex zones oriented to the center of the flow. Slag is removed by evacuation of central portion of the flow. The rest of the flow used to annularly flush split zone of the central portion is subjected to further dilatation to form annular flow with restricted outside and inside regions. Fullerene-containing material is discharged from the bulk of the flow restricted by offtakes in its cross-section.

EFFECT: enhanced process efficiency.

4 dwg

FIELD: chemical industry; other industries; devices for production of the solid-phase nanostructured materials.

SUBSTANCE: the invention is pertaining to the nanotechnologies and may be used at production of the carbonic nanotubes. The invention provides, that in the steam generator (4) they prepare multiphase mixture of the initial substance and route it under pressure to the gasodynamic resonator (9), where the mixture detonates. The products of the detonation combustion through the nozzle (2) are fed in the chamber (3), extended and cooled forming clusters. The produced clusters are routed onto the target (12) with the formation die (1) arranged in the chamber (3). The substrate (11) of the target (12) is supplied with the temperature control device providing the cyclical heating and cooling. The formation and growth of the solid-phase nanostructured materials takes place on the formation die (1). As the pressure in the gasodynamic resonator (9) drops, the feeding of the multiphase mixture in it is restarts and the process repeats. The invention allows to provide the optimal conditions of the growth of the nanostructured materials and due to it to increased efficiency of the process.

EFFECT: the invention ensures provision of the optimal conditions for the growth of the nanostructured materials and the increased efficiency of the process.

1 dwg

FIELD: processes for modifying porous carriers such as photon crystals on base of SiO2 by means of inclusions phases of ferromagnetic metal or their oxides, possibly in functional micro-electronics, development of different type of magneto-optic systems for information recording, as sensing members of weak magnetic field pickups.

SUBSTANCE: method comprises steps of successively impregnating sample of photo crystal by solutions of ionic salts of metals; treating it in solution of oxalic acid; then annealing in air at 600 - 700 K for 1 - 2 h for further reduction at 700 K in hydrogen for 0.5 - 1 h or baking in inert atmosphere at 700 - 800 K for 1 - 2 h. Usage of ferromagnetic phases including such metals as Fe, Co, Ni and their oxides allows produce materials with magneto-optic properties.

EFFECT: volume occupation, namely of near-surface layers of photon crystal with inclusions of ferromagnetic phases.

1 dwg

FIELD: vacuum engineering; production of carbon nano-tubes from graphite paper used as auto-electronic emission sources.

SUBSTANCE: proposed method consists in modification of graphite paper coated with silica gel applied by means of current firing. First silica gel is applied on graphite paper surface. Silica gel contains nitrates of metals used as catalyst, mainly Fe, Co, Ni or their alloys. Then, paper is placed in vacuum plant and pressure of (1-5)·10-5 is built up. Such limit ensures minimum residual atmosphere of inert gas. Then, graphite paper is subjected to modification by current firing. Carbon nano-tubes are formed at temperature of 650-750°C. Proposed method is effective in production of nano-tubes with insignificant defects at diameter ranging from 10 to 100 nm.

EFFECT: facilitated procedure and low cost.

4 dwg

FIELD: electronic-vacuum engineering.

SUBSTANCE: invention is intended for implementation in manufacture of light sources, indicator lamps, and optic displays. Graphite heater is placed in working volume, into which nitrogen or nitrogen/argon blend (ratio from 1:10 to 1:1) is pumped in at pressure up to 15 MPa and removed. These operations are repeated threefold. Thereafter, above-indicated gas or gas blend is pumped in at pressure 10 to 90 MPa and working volume is heated to 2100-2200 K at velocity 1 to 100 K/min and aged for 10 min to 4 h. Temperature is the lowered to ambient value and then pressure is reduced to atmospheric value at velocity 1 MPa/sec. Resultant nitrogen-carbon nanofibers are withdrawn from working volume, dispersed in ethyl alcohol by means of ultrasonic disperser giving power 180-200 W for 5-15 min, filtered, and applied onto cathodic plate.

EFFECT: enabled manufacture of various-structure nanofibers in large amounts by easy and economic way.

3 cl, 6 dwg, 1 tbl, 7 ex

FIELD: nanotechnology.

SUBSTANCE: proposed method for producing calibrated nano-capillary includes continuous monitoring of capillary diameter against set gage using monatomic gas as so-called minimal-diameter plug and molecular gas, as maximal-diameter plug; passage of mixture of these gases through capillary blank; evaluation of capillary diameter by variation in concentration ratio of atomic and molecular gases at controlled decomposition of gas mixture component within capillary. Device implementing this method has capillary blank and capillary holder incorporating capillary heater. Use is made of atomic- and molecular-gas filled cylinders; gas outlets of these cylinders communicate with gas mixer and gas mixture is passed from mixer outlet to mass-spectrograph though leak and capillary blank being heated.

EFFECT: ability of in-process monitoring of capillary diameter.

2 cl, 1 dwg, 2 tbl

FIELD: electronic engineering.

SUBSTANCE: method of formation of nano-sized clusters and of creation of ordered structures of them is based upon introduction of solution, containing material for formation of clusters, into material of substrate and in subsequent influence of laser radiation pulse onto the solution till generation of low-temperature plasma in it. Restoration of material of cluster to pure material takes place as a result of crystallization of the solution onto liquid substrate during process of plasma cooling down. Single-crystal quantum points are formed in channels of nano-sized pores, which points are joined with material of substrate. Not only two-dimensional array of clusters but three-dimensional array of clusters can be produced. There is also capability of creation of joined clusters composed of different materials.

EFFECT: improved efficiency.

11 cl, 8 dwg

FIELD: microelectronics, nanoelectronics, and semiconductor engineering; producing quantum device components and quantum-effect structures.

SUBSTANCE: proposed method for producing quantum dots, wires, and components of quantum devices includes growing of stressed film from material whose crystalline lattice constant is higher than that of substrate material. Thickness of stressed film being grown is smaller than critical value and film is growing as pseudomorphous one. Sacrificial layer is grown between stressed film and substrate which is then selectively removed under predetermined region of film thereby uncoupling part of the latter from substrate; this part is bulged or corrugated with the result that film stress varies causing shear of conduction region bottom (top of valence region) and formation of local potential well for carriers. In addition, stressed film may be composed of several layers of different materials; it may also have layer mainly holding charge carriers and layer practically free from charge carriers.

EFFECT: facilitated manufacture of quantum structures, enlarged range of materials used, and improved characteristics of components produced.

4 cl, 7 dwg

FIELD: nano-engineering; manufacture of nano-structures; methods of production of nano-fibers.

SUBSTANCE: proposed method consists in forming multi-layer structure on substrate; multi-layer structure includes at least one sacrificial layer and film structure from agent used for forming the fibers and divided into narrow strips; sacrificial layer is selectively removed and narrow strips are released from substrate, thus forming fibers. Multi-layer structure may include several sacrificial layers and several layers from which fibers will be formed. Film structure is divided into strips after growing or it is initially divided into narrow strips by forming it on special-pattern substrate. Proposed method makes it possible to obtain nano-fibers possessing high strength and resistance to surrounding medium. Process is compatible with standard technologies of manufacture of integrated circuits.

EFFECT: enhanced efficiency.

10 cl, 4 dwg

FIELD: nanoelectronics, microelectronics; microelectronic and microelectromechanical systems; manufacture of micro- and nanoprocessors and nanocomputers.

SUBSTANCE: proposed method consists in bringing the electrode to substrate surface, after which electrostatic potential which is negative relative to substrate surface point is fed to electrode; substrate is preliminarily placed in damp atmosphere and water adsorption film is formed on its surface, after which electrode is brought to substrate surface in such way that water adsorption film wets electrode; electrode is brought in contact with substrate surface; simultaneously with feed of electrostatic potential to electrode and electrode is subjected to pressure relative to substrate surface.

EFFECT: increased penetration into substrate volume (from 10 nm to 50 nm) of dielectric sections of oxide films.

17 cl, 3 dwg, 5 ex

FIELD: production of anti-bacterial and sterilizing substances, conducting adhesives and inks and protective screens of graphical displays.

SUBSTANCE: proposed colloidal solution is prepared through dissolving the metal salt and water-soluble polymer in water and/or nonaqueous solvent. Then, reaction reservoir with solution thus obtained is blown with gaseous nitrogen or argon and is subjected to radioactive radiation, after which solution is additionally diluted and treated with ultrasound. Used as metal salt is silver salt, for example nitrate, perchlorate, sulfate or acetate. Use may be also made of nickel, copper, palladium or platinum salt. Used as polymer is poly vinyl pyrrolidone, copolymer of 1-vinyl pyrrolidone with acryl or vinyl acetic acid, with styrene or vinyl alcohol. Used as nonaqueous solvent is methanol, ethanol, isopropyl alcohol or ethylene glycol. In production of metal-polymer nano-composites, use may be made of polymer stabilizer, for example, polyethylene, polyacrylonitrile, polymethyl methocrylate, polyurethane, polyacrylamide or polyethylene glycol instead of water-soluble polymer. In this case, surfactant may be additionally introduced into reaction reservoir for obtaining the emulsion. Solution remains stable for 10 months at retained shape of particles and minor increase of their size. Freshly prepared colloidal solution contains nano-particles having size not exceeding 8 nm.

EFFECT: smooth distribution of nano-particles of metal in polymer.

24 cl, 13 dwg, 1 tbl, 7 ex

FIELD: polymer production.

SUBSTANCE: invention relates to a gas-phase process for producing polyethylene from ethylene in fluidized-bed reactor, which process comprises: (i) hydrogenation stage, wherein supplied ethylene including impurities or secondary components such as acetylene and ethane reacts with hydrogen to remove acetylene via catalytic hydrogenation and to form ethylene, while a part of ethylene is converted into ethane; and (ii) polymerization stage, hen ethylene leaving stage (i) reacts in gas phase in fluidized-bed reactor to form polyethylene, wherein fluidizing gas contains, at the entry of reactor, ethylene and ethane in amount 20 to 70% based on the total volume of fluidizing gas, optionally with other components.

EFFECT: reduced investment and energetic expenses and increased yield of product for one pass in unit time.

5 cl, 2 dwg, 1 tbl, 3 ex

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