Method of hydrogen storage by carrying out catalytic reactions of hydration/dehydration of aromatic substrates under action of shf (hf) radiation

FIELD: chemistry.

SUBSTANCE: invention relates to the field of catalysis and organic chemistry, in particular, to method of intensification of catalytic reactions under action of SHF (HF) radiation with essential reduction of energy consumption, which can be used when producing devices for hydrogen storage based on reversible reactions of hydration-dehydration of aromatic compounds. Method of hydrogen storage is based on carrying out reversible catalytic reactions of hydration-dehydration of organic substrate by heating it for absorption and releasing hydrogen using heterogeneous catalyst. As organic substrate, aromatic polycyclic hydrocarbons or aromatic oligomers are used. Heterogeneous catalyst includes carbonic or oxide carrier and active metal applied on it, chosen from the line Pt, Pd, Ni in amount of 0.1 to 15 weight %. Stage of hydrogen absorption and its release from organic substrate is carried out under action of SHF or HF radiation on the said heterogeneous catalyst.

EFFECT: increased rate of hydration and dehydration reactions.

5 cl, 6 ex

 

The invention relates to the field of catalysis and organic chemistry, in particular, to a method of intensification of catalytic reactions under the influence of microwave(RF)radiation with a significant reduction of energy consumption that can be used to create devices for hydrogen storage based on reversible reactions hydrogenation-dehydrogenation of aromatic compounds.

The present invention is the creation of a fundamentally new technology of hydrogen storage by implementing catalytic reactions of hydrogenation-dehydrogenation of aromatic substrates under conditions of microwave(RF)activation of the reaction mixture to the catalyst in order to reduce the energy consumption of catalytic processes and system capacity of hydrogen at relatively low temperatures of the processes of hydrogenation-dehydrogenation through targeted energy supply microwave(RF)radiation to the catalysts, in comparison with those already used by the methods of heat for carrying out reactions of hydrogenation-dehydrogenation with the purpose of storing hydrogen, such as electric heaters or heating the reaction mixture combustion gases. An important task is the development of catalysts capable of selectively absorb the energy of high frequency radiation.

Intensification method of catalytic hydrogenation reactions of degidio the ing devices for hydrogen storage is selective exposure to microwave(RF)radiation on the catalyst, where there is no need of thermal heating of the entire catalytic composite material. In this way the microwave(RF)energy is converted into heat for heating the active centers of the catalyst, providing the conversion of the substrate in the reaction products. Option pre-treatment catalysts microwave(RF)radiation, which improves their catalytic properties (conversion of the substrate in the reactions of hydrogenation-dehydrogenation and hydrogen yield in the reaction of dehydrogenation).

The proposed method can be implemented when carrying out reactions in static conditions or in a flow reactor under the condition that the material of the catalytic reactor does not absorb microwave(RF)radiation (glass, quartz, ceramic or other composite materials).

Catalytic composites that are used as materials for hydrogen storage, are mixtures consisting of: (1) a source of hydrogen organic compounds (aromatic and heteroaromatic hydrocarbons, including condensed polycyclic or aromatic polymers) or fullerenes, capable of reversibly and repeatedly gidrirovaniya to degidrirovaniya, (2) catalyst, in the form of a semiconductor material that absorbs microwave(RF)radiation and capable of gidrirovanii to degidrirovanii organic compound. As the catalyst used noble metals (Pt, Pd and others) or Nickel deposited on a carbon or oxide media (for example, Sibunit, activated carbon, oxides of titanium, zirconium and other transition metal mixed oxide system).

The solution of fundamental problems of low and efficient conversion of hydrocarbons, in particular, in the process of hydrogen storage based on reversible cycles of hydrogenation-dehydrogenation of aromatic and heterocyclic substrates with the aim of producing hydrogen in fuel cells can have a significant impact on the rational use of raw materials, reduce energy costs. Promising is the use of electro-physical methods of influence on the catalyst and reaction mixture. Absorption catalysts energy of the electromagnetic field of high or ultra-high frequency significantly affects the change in their properties. Changing the parameters of electromagnetic exposure, it is possible to achieve the controlled effect in the conversion of hydrocarbons.

Under microwave catalysis volume is controlled electromagnetic influence catalyst - reagents, which changes its state and the efficiency of the catalyst, the selectivity of the conversion of raw materials into valuable products and stability of the catalyst. One of the fundamental the x directions of implementation of this approach is temperature reduction and energy for the reaction, the increase in activity, selectivity and stability of catalysts by means of the translation process in the soft mode in the electromagnetic microwave(RF)field, while maintaining or increasing the productivity of the process.

Recently, this new direction associated with the use of microwaves /S.L.Suib, SATTEN 2 (1998) 75/, was developed in catalysis. The effects observed in catalysis when exposed to microwaves is still unclear and poorly understood, although it is obvious that the microwave irradiation(HF)-absorbing materials (catalysts, carriers and reaction medium) can cause rapid volumetric heating, modify surface properties. This distinguishes the effect of microwave(RF) from traditional thermal effects, which is used in the preparation of catalysts and reactions.

Solid materials according to the nature of the interaction with the microwave(RF)radiation can be divided into three groups /Berdonosov S., Berdonosov became popular, Znamenskaya IV, Microwave radiation in chemical practice // Chem. technology. 2000. No. 3. C.2-8/. The first group includes metals, smooth surface which totally reflects the microwave(RF)radiation. This metal is not heated, because of the energy losses of the microwave(RF)radiation in its volume almost none. The second group belong dielectrics, passing ST is(RF)radiation through its volume almost unchanged: fused silica, various kinds of glass, porcelain and faience, polyethylene, polystyrene and Teflon (Teflon, and others).

Finally, the third group belong dielectrics, when passing through the volume of which is absorbed microwave(RF)radiation, involving, in particular, heating of the samples. In practice, for high frequency(HF)heating often use a mixture containing substances, weakly and strongly absorbing microwave(RF)radiation. Changing the composition of such mixtures, it is possible to adjust the maximum temperature of the mixture and composition of the resulting reaction products.

The absorption of microwave(RF)radiation is due to two factors. First, when applying the microwave(RF)fields the motion of the dipoles (polar molecules or other marginalized groups of atoms) acquires a certain orientation associated with the nature of the imposed field. When the intensity of the microwave(RF)field is reduced, the resulting orientation disappears and the randomness of rotational and vibrational motion of the molecules is restored, while thermal energy is released. At a frequency of 2.45 GHz, the orientation of the dipoles of the molecules and their disorder may occur several billion times in 1 s, which leads to rapid heating of the sample. It should be noted that domestic microwave ovens have a multimode resonator, and the energy is changed at a fixed frequency 0,915 GHz or 2.45 GHz (depending on the country the manufacturer).

In catalysis the use of microwaves is developing in two directions. The first direction is associated with the sample preparation of catalyst using microwave(HF) and their further application in traditional reactors, where the heating is performed in a traditional thermal methods - ex situ microwave(RF) catalysis /Appl. Catal., A: General 204, 2000, 191/. The second is the effect on the catalyst and reaction medium (if it absorbs the microwaves in chemical catalytic reaction /J. Catal., 211, 2002, 560/. In the first case, there is only preliminary transformation properties of the catalyst, and the second selective effect on those system components that are able to absorb the energy of the microwaves.

In the work /Catal. Lett, 35, 1995, 345/ it was shown that under the action of microwaves vary the sizes of the metal particles Pd/Al2About3and Pd/SiO2catalysts that led to increased activity and stability in the reaction of hydrogenation of benzene. In some works, not related to the storage or production of hydrogen, but also with the reactions of hydrogenation-dehydrogenation /for example, Appl. Catal., 34, 2001, 129/ effect was observed a significant reduction of the temperature of the beginning of the reaction and increasing the activity of the catalysts at low temperatures in comparison with thermally activated processes.

Storage of hydrogen is extremely urgent p is oblama, the solution of which will allow to switch from fossil fuel to hydrogen in transportation and power plants. Currently available materials for hydrogen storage - metal hydrides and carbon nanotubes remain ineffective because hydrogen capacity for them is usually no more than 2-4 wt.%. There are several intermetallic compounds (e.g., Mg2Ni), for which the capacity reaches 5 wt.%, however, this value is achieved only at high temperatures, which reduces the efficiency of such systems.

The most promising way to store hydrogen is to use catalytic systems that are able to reversibly gidrirovanii to degidrirovanii organic substrates, for example a pair of benzene-cyclohexane and naphthalene-decalin /for example, Jpn. Patent No. 198469 A, 2001; Hodoshima, S., Saito Y. et al., Int. J. Hydrogen Energy, 28 (2003) 1255).

In US Pat. No.6653503; 6075422 and 5328577 microwave energy was used for transformation of CH4With2H6With3H8in unsaturated hydrocarbons and hydrogen. The disadvantage of these methods is the low hydrogen capacity of such organic substrates, which limits their use in devices for hydrogen storage.

There is a method of storing hydrogen /Int. J. Hydrogen Energy, 28, 2003, 197/, in which it is proposed to use reversible catalytic reaction guy who compete naphthalene (on stage charging with hydrogen and a dehydrogenation decline (at the stage of evolution of hydrogen) using a heterogeneous catalyst. The disadvantage of the proposed solution is that the dehydrogenation reaction begins only at temperatures above 205°With (effectively at 280°C), while the boiling temperature of the substrate (S-TRANS-decalin, S-CIS-decalin) below, which leads to the inevitable drift of the organic substrate at the stage of discharge of hydrogen from the device under normal temperature heating. This method is the closest to the offer.

The technical problem to be solved in the present invention is to reduce the entrainment of organic substrate from the system during high-temperature dehydrogenation reaction under hydrogen, and reduced energy costs for heating the catalytic composite systems based on reversible reactions of hydrogenation of the aromatic substrates and dehydrogenation of the corresponding hydrogenated hydrocarbons in the modes of its charging and discharging hydrogen while maintaining high speeds of the reactions of hydrogenation and dehydrogenation.

The problem is solved in that in the proposed method of hydrogen storage based on the implementation of reversible catalytic reactions of hydrogenation-dehydrogenation of the organic substrate by heating it to absorb and hydrogen using a heterogeneous catalyst, according to izaberete the Oia as an organic substrate using an aromatic polycyclic hydrocarbons or aromatic oligomers, the heterogeneous catalyst comprises a carbon or an oxide carrier and the applied active metal selected from the range of Pt, Pd, Ni, in an amount of from 0.1 to 15 wt.%, at this stage of absorption of hydrogen and separating it from the organic substrate is carried out when exposed to microwave or RF radiation on the specified catalyst.

The effect of microwave or RF energy is preferably carried out at atmospheric pressure and temperatures from 20 to 100°for the stage of absorption of hydrogen and from 100 to 200°for stage dehydrogenation.

For the preliminary activation of catalyst used his handling of the influence of microwave or RF radiation in a stream of gas, for example, inert gas, or hydrogen, or oxygen.

Catalytic reaction of hydrogenation-dehydrogenation is carried out in a static or dynamic conditions.

As the organic substrate at the stage of hydrogen using an aromatic polycyclic hydrocarbons or aromatic oligomers having a boiling point above 200°to avoid entrainment of the system with a stream of hydrogen under conditions of microwave heating.

The essence of the proposal is that the proposed method for the reactions of hydrogenation or dehydrogenation catalyst composite material (in the static conditions of the reactions) or utilizator (in the dynamic conditions of the reaction in a flow reactor) are not traditional heating with the electric furnace (either gas burners or heat exchangers in industrial installations), and the effects of microwave(RF)radiation of various capacities. There is a significant temperature reduction stages of charging and discharging catalytic composite with hydrogen when activating the microwave(RF) field, which leads to the reduction of entrainment of the organic substrate. Option pre-activation of the catalyst by exposure to microwave(RF)radiation in current various gases (inert gases, hydrogen, oxygen, and others)prior to the main process.

As sources of microwave(RF)radiation can be used in domestic microwave oven with multimode resonator with a fixed frequency 0,915 GHz or 2.45 GHz, or any industrial or semi-industrial microwave(RF)generators, in combination with the amplifier and resonator optimum design capacity from 20 to 5000 watts or more, operating at a frequency of from 0,915 to 9.0 GHz.

According to the invention as a source of hydrogen (organic substrate) are organic compounds (aromatic hydrocarbons and heterocyclic compounds, including condensed polycyclic, for example benzene, terphenyl, naphthalene, cyanonaphthalene, paradisian benzene or aromatic polymers and oligomers, such as Polyphenylene)capable of reversibly and repeatedly gidrirovaniya to degidrirovaniya.

As the organic substrate on St is in the course of its release it is advisable to use these substances with boiling points above 200° To prevent ash from the system with a stream of hydrogen under conditions of microwave heating.

According to the invention, the heterogeneous catalyst comprising a material that absorbs the energy of the microwave(RF)radiation, i.e. characterized by the tangent of the dielectric loss of the semiconductor material or a conductor of electric current), consists of carbon or oxide media with high surface area activated carbon; graphitized carbons type of Sibunit, oxides of titanium, zirconium, gavinia, transition metal oxides or mixed oxides containing transition metal oxides, and the oxides of silicon and aluminum) and an active metal (Pt, Pd, Ni) in an amount of from 0.1 to 15 wt.%, preferably from 0.5 to 5 wt.%.

Catalysts containing platinum, palladium or Nickel, or other metals of the platinum group, is prepared by impregnation of the carrier (FC) from aqueous solutions of salts or complexes of the active metals, such as Ni(NO3)2N2PtCl6or H2PdCl4, followed by drying in air at 100 to 150°and a recovery current of hydrogen at 100-400°C, preferably at 200 to 300°C. the Catalysts can also be prepared by spraying the active component from the gas phase with the use of volatile compounds such as CARBONYLS of metals. Already on studiophotography catalysts on their surface are formed finely dispersed particles of noble metal or Nickel, which is highly active in the reactions of hydrogenation and dehydrogenation.

Heating of the catalyst or all of the catalytic composite is due to the absorption of microwave(RF)radiation or particles of metal, or a carrier capable of absorbing microwave(RF)radiation. The coefficient of efficiency (the degree of efficiency of absorption of microwave(RF)energy) may range from a few percent, as in the use of domestic microwave ovens, up to 60-90% when using resonators special design.

As a material of a catalytic reactor for hydrogen storage are used dielectrics, transparent to microwave or RF radiation, such as quartz, various glass, porcelain and faience, polyethylene, polystyrene or Teflon, Teflon, or other.

The temperature in the catalyst bed or catalytic composite material can be measured either using reference samples, sealed in glass vials and placed in the catalyst bed or composite, or a special IR-pyrometers or other non-contact temperature measurement.

Technical result achieved - high speed reactions of hydrogenation and dehydrogenation, a significant reduction in temperature stages of charging and discharging catalytic composite with hydrogen when activating the microwave(RF)field is yasnyayutsya fact, when exposed to microwave(RF)radiation on the catalytic composite material is heated only the catalyst, and most effectively heated particles deposited metal, and not all catalytic composite system as a whole. An additional effect is the reduction of entrainment of material source of hydrogen included in the catalytic composite systems, high-temperature phase extraction of hydrogen during the reaction of dehydrogenation.

The drawing shows curves of the amount of hydrogen released during dehydrogenation in static conditions, from the time of microwave exposure to catalytic compositions:

a - 15% Pt/C (0.5 g) articlecan (10 g), power UHF 440 watts (Tcomp=190°)

b - 15% Pt/C (0.5 g) articlecan (10 g), thermal dehydrogenation (Tcomp=320°)

65% Ni/SiO2-Al2O3(0.2 g) - decalin (5 g), the power of the microwave - 1000 watts (Tcomp=145°)

The invention is illustrated in the following examples.

Example 1

In a glass container load of 0.5 g of the catalyst 15% Pt/C (activated carbon) and 10 g of articlecan (fully hydrogenated terphenyl), put the container into the chamber household microwave ovens and for a fixed power (440 watts) at atmospheric pressure measure the kinetics of hydrogen from catalytic composite material. To icesto hydrogen, capable of theoretically be released by the dehydrogenation just downloaded articlecan, is 8.7 liters. Used catalytic system with a total weight of 10.5 g is able to accumulate about 7.7 wt.% hydrogen per digidrirovanny product.

The kinetic curve of hydrogen is shown in the drawing (curve a). For comparison, in the drawing, curve (b) shows the curve of hydrogen by thermal heating of the catalytic composite system 320°C. it is Seen that under conditions of microwave reaction temperature of the catalytic composite system is only 190°while there is a high rate of hydrogen from the system (about 4.5 l/h). Under conditions of thermal reaction at a temperature of 320°With the rate of hydrogen is more than an order of magnitude lower.

Example 2

The catalytic composite system was tested in the method according to example 1 with the difference that the catalyst used 65% Ni/aluminosilicate, and as a source of hydrogen - decalin that is reversible can degidrirovaniya in naphthalene. The power of microwave radiation was 1000 watts. The amount of hydrogen theoretically able to stand out in the dehydrogenation just downloaded decline is to 7.25 liters. Used catalytic system with a total weight of 10.5 g is able to accumulate the Colo 6.2 wt.% hydrogen per digidrirovanny product (naphthalene).

The kinetic curve of hydrogen is shown in the drawing (curve b). The temperature of the catalytic composite system is 145°C, and the rate of hydrogen from the system is about 0.5 l/h). In terms of heat of reaction at this temperature, hydrogen does not occur.

Example 3

In the autoclave load of 0.6 kg of catalyst 5% Pt/C (activated carbon) and 10 g of 1,4-diphenylbutadiyne representing polyacetylenic oligomer (dimer), and at a pressure of 70 ATM and stirring with a speed of 500 Rev/min, heat the mixture to 160°C and maintained for 2 hours.

The results of the experiments show that complete hydrogenation of 1,4-diphenylbutadiyne to 1,4-dicyclohexylmethane in these conditions occurs within 110-120 minutes.

Example 4

In the autoclave load of 1 kg of catalyst 5% Pt/C (activated carbon) and 10 g of 1,4-dicyclohexylmethane and under atmospheric pressure and stirring with a speed of 500 Rev/min, heat the mixture to 320°C and maintained for 4 hours. The total amount of hydrogen released from the closed system (autoclave), amounted to about liters of 10.05 or 0,99, This means that the capacity of 1,4-dicyclohexylmethane hydrogen is 9.9 wt.%.

Example 5

Microwave energy from the microwave generator (frequency of 2.375 GHz) waveguide is served in a special volnovod the second reactor, loaded with 1 cm3catalyst 5% Pt/C (Sibunit). At the same time in the reactor is supplied with a flow of reagents (cyanonaphthalene with a speed of 0.4 g/hour and the hydrogen 150 cm3/min). The result of the interaction of the catalyst-reagent with microwave(RF)field is heated and flows through the chemical reaction of hydrogenation.

At the outlet of the reactor during hydrogenation with a conversion of 90% is formed decalin methylene amine.

Example 6

In example 6 in the reactor is supplied with a flow of reagents (pair-dicyanobenzene at a rate of 0.5 g/hour and hydrogen at 200 cm3/min). The result of the interaction of the catalyst-reagent with microwave(RF)field is heated and flows through the chemical reaction of hydrogenation.

At the outlet of the reactor during hydrogenation with a conversion of 85%, a para-dimethylaminoethoxy.

The experiments showed also an increase in the yield of the organic substrate in the case of pre-treatment of the catalyst in a stream of inert gas (argon, or hydrogen, or oxygen exposure to RF or microwave radiation.

The experiments showed also an increase in the yield of the organic substrate when used as the oxide carrier oxides of titanium, zirconium, hafnium, transition metal oxides, and mixed oxides containing transition metal oxides, oxides of silicon and aluminum.

The reason for microwave asset is the catalyst in a stream of gases is the influence of an electric field directly to the metal complexes, that leads to its higher dispersion on the surface of the carrier and thereby to changes in catalytic properties. In addition, when the microwave(RF)heating the metal particles are heated to a higher temperature than the medium that facilitates the flow of selective hydrogenation reactions of aromatic substrates and dehydrogenation of naphthenes at lower effective temperatures of the catalytic layer than when using Terminalia. The most effective catalysts for the implementation of the proposed method are catalysts based on carbon carriers and oxides of transition metals, which can deliver maximum efficiency to absorb microwave(RF)radiation. Thus, the resulting system can store hydrogen with a capacity of up to 7.7 wt.% at temperatures refills not above 100°and the temperature of hydrogen is not above 200°C.

1. The method of hydrogen storage based on the implementation of reversible catalytic reactions of hydrogenation-dehydrogenation of the organic substrate by heating it to absorb and hydrogen using a heterogeneous catalyst, wherein the organic substrate using an aromatic polycyclic hydrocarbons or aromatic oligomers, heterogeneous catalyst includes the carbon or oxide carrier and the applied active metal, chosen from a number of Pt, Pd, Ni, in an amount of from 0.1 to 15 wt.%, at this stage of absorption of hydrogen and separating it from the organic substrate is carried out when exposed to microwave or RF radiation on the specified heterogeneous catalyst.

2. The method according to claim 1, characterized in that the impact of microwave or RF radiation is carried out at atmospheric pressure and temperatures from 20 to 100°for the stage of absorption and from 100 to 200°for stage dehydrogenation.

3. The method according to claim 1, characterized in that for the preliminary activation of catalyst used his handling of the influence of microwave or RF radiation in a stream of gas, such as inert gas, or hydrogen, or oxygen.

4. The method according to claim 1, characterized in that the catalytic reaction of hydrogenation-dehydrogenation is carried out in a static or dynamic conditions.

5. The method according to claim 1, characterized in that the quality of the organic substrate at the stage of hydrogen using an aromatic polycyclic hydrocarbons or aromatic oligomers having a boiling point above 200°to prevent ash from the system with a stream of hydrogen under conditions of microwave heating.



 

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17 cl, 2 tbl, 24 ex

FIELD: technological processes.

SUBSTANCE: inventions may be used for preparation of shielded arc atmospheres, which contain nitrogen with hydrogen or nitrogen with hydrogen and carbon oxide that are used in glass, metallurgical, machine building industries. The first variant of shielded arc atmosphere preparation includes conversion of hydrocarbon gas, steam conversion of carbon oxide, cooling of conversion products with separation of condensed moisture and final purification of gas mixture from carbon dioxide and moisture at adsorption plants. Conversion of hydrocarbon gas is carried out in three stages: the first stage is carried out in free volume of device for oxidation of hydrocarbon gas with air; the second stage is carried out in volume of device that is filled with granular fire-resistant material for performance of steam and carbon-dioxide conversion of remaining hydrocarbon gas; the third stage is carried out in volume of device, which is filled with heat-resistant metal rings for saturation of gas flow with moisture and performance of steam conversion of carbon oxide. The second variant of shielded arc atmosphere includes conversion of hydrocarbon gas, steam conversion of carbon oxide, cooling of conversion products with separation of condensed moisture and final purification of gas mixture from carbon dioxide and moisture at adsorption plants. At that catalytic conversion of carbon oxide is regulated by amount of water vapors condensate, which is supplied into volume of device that is filled with heat-resistant metal rings for saturation of gas flow with moisture. The third variant of shielded arc atmosphere includes conversion of hydrocarbon gas, steam conversion of carbon oxide, cooling of conversion products with separation of condensed moisture and final purification of gas mixture from carbon dioxide and moisture at adsorption plants. At that part of hydrocarbon gas conversion products is sent to cooling device, bypassing device of steam conversion of carbon oxide, and further to adsorption purification unit in order to maintain preset content of carbon oxide in shielded arc atmosphere.

EFFECT: inventions allow to intensify the process and to prepare shielded arc atmosphere of triple composition.

4 cl

FIELD: chemistry.

SUBSTANCE: way of syngas cleaning includes: introduction of the flow of initial syngas, into the feed zone of the distillation column, flow expansion of the liquid remainder from the distillation column by means of a dilator of liquids with the extraction of work for forming the flow of the cooled waste liquid, the rectification of vapour from the feed zone for forming the upper flow of vapour with the decreased content of nitrogen and inert gases, cooling of the upper vapour flow in the indirect heat exchange with the flow of the cooled waste liquid for forming the of partially condensed upper flow and flow of the partially heated waste liquid, separation of the partially condensed upper flow into the flow of condensate and the flow of the purified vapour of syngas with the decreased content of nitrogen and inert gases and the irrigation of distillation column by the flow of condensate. By the first variant the method of production of ammonia includes reforming of hydrocarbon for forming syngas, cooling the flow of initial syngas, expansion of the cooled flow of initial syngas, introduction of the extended flow of initial syngas in the feed zone in the distillation column, flow expansion of liquid remainders from the distillation column with the aid of the dilator of liquid forming the flow of cooled waste liquid, according to the first variant the method of the production of ammonia includes reforming of hydrocarbon for forming syngas, cooling of a stream initial syngas, expansion of the cooled stream initial syngas, introduction of the extended flow of initial syngas in the feed zone in the distillation column, flow expansion of liquid remainders from the distillation column with the aid of the dilator of liquid for forming the flow of the cooled waste liquid, the rectification of vapour from the feed zone in the distillation column for forming the upper flow of vapour with the decreased content of nitrogen and inert gases, cooling the upper flow of vapour in the indirect heat exchange with the flow of the cooled waste liquid for forming of partially condensed upper flow and flow of the partially heated waste liquid, the separation of the partially condensed upper flow into the flow of condensate and the flow of purified vapour of syngas with the decreased content of nitrogen and inert gases, the irrigation the distillation column by the flow of condensate, heating the flow of the purified vapour of syngas in the heat exchanger with the cross-section flow, heating the flow of partially heated waste liquid in the heat exchanger with a cross-section flow, the supply of the flow of the purified vapour of syngas from the heat exchanger with the cross-section flow into the outline of synthesis of ammonia. According to the second variant the method of the production of ammonia includes the reforming hydrocarbon with excess air for forming the flow of initial syngas, removal of nitrogen and inert gases from the flow of the syngas by distillation, thus provide cooling with the aid of the expansion of the liquid by means of the dilator-generator, and the upper flow partially condense the waste flow, cooled by means of expansion of the liquid remainder from the distillation column, and the supply of syngas with the decreased content of nitrogen and inert gases from distillation into the contour of the synthesis of ammonia at which the liquid remainders expand by means of the dilator of liquid with the extraction of work.

EFFECT: invention makes it possible to improve industrial and economic characteristics.

18 cl, 5 dwg, 3 tbl

FIELD: chemistry.

SUBSTANCE: way of syngas cleaning includes: introduction of the flow of initial syngas, into the feed zone of the distillation column, flow expansion of the liquid remainder from the distillation column by means of a dilator of liquids with the extraction of work for forming the flow of the cooled waste liquid, the rectification of vapour from the feed zone for forming the upper flow of vapour with the decreased content of nitrogen and inert gases, cooling of the upper vapour flow in the indirect heat exchange with the flow of the cooled waste liquid for forming the of partially condensed upper flow and flow of the partially heated waste liquid, separation of the partially condensed upper flow into the flow of condensate and the flow of the purified vapour of syngas with the decreased content of nitrogen and inert gases and the irrigation of distillation column by the flow of condensate. By the first variant the method of production of ammonia includes reforming of hydrocarbon for forming syngas, cooling the flow of initial syngas, expansion of the cooled flow of initial syngas, introduction of the extended flow of initial syngas in the feed zone in the distillation column, flow expansion of liquid remainders from the distillation column with the aid of the dilator of liquid forming the flow of cooled waste liquid, according to the first variant the method of the production of ammonia includes reforming of hydrocarbon for forming syngas, cooling of a stream initial syngas, expansion of the cooled stream initial syngas, introduction of the extended flow of initial syngas in the feed zone in the distillation column, flow expansion of liquid remainders from the distillation column with the aid of the dilator of liquid for forming the flow of the cooled waste liquid, the rectification of vapour from the feed zone in the distillation column for forming the upper flow of vapour with the decreased content of nitrogen and inert gases, cooling the upper flow of vapour in the indirect heat exchange with the flow of the cooled waste liquid for forming of partially condensed upper flow and flow of the partially heated waste liquid, the separation of the partially condensed upper flow into the flow of condensate and the flow of purified vapour of syngas with the decreased content of nitrogen and inert gases, the irrigation the distillation column by the flow of condensate, heating the flow of the purified vapour of syngas in the heat exchanger with the cross-section flow, heating the flow of partially heated waste liquid in the heat exchanger with a cross-section flow, the supply of the flow of the purified vapour of syngas from the heat exchanger with the cross-section flow into the outline of synthesis of ammonia. According to the second variant the method of the production of ammonia includes the reforming hydrocarbon with excess air for forming the flow of initial syngas, removal of nitrogen and inert gases from the flow of the syngas by distillation, thus provide cooling with the aid of the expansion of the liquid by means of the dilator-generator, and the upper flow partially condense the waste flow, cooled by means of expansion of the liquid remainder from the distillation column, and the supply of syngas with the decreased content of nitrogen and inert gases from distillation into the contour of the synthesis of ammonia at which the liquid remainders expand by means of the dilator of liquid with the extraction of work.

EFFECT: invention makes it possible to improve industrial and economic characteristics.

18 cl, 5 dwg, 3 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to dehydrogenation or reforming of alcohols, in particular to a method of dehydrogenation of the primary alcohol, such as methanol or ethanol, for obtaining hydrogen, in particular for use in a fuel element with the purpose of obtaining electrical energy. In the method of dehydrogenation a catalyst containing copper is used, which includes a metallic carrier. To solve the given challenge the method includes bringing to contact of the initial raw mixture of the gases containing alcohol, with the catalyst of reforming in order to obtain a mixture of products of reforming, containing hydrogen, and the catalyst for reforming the contains a metallic spongy carrier and a coating on copper, at least, partially covering surface of the given metal spongy carrier where the given metal spongy carrier is obtained by means of the method including the leaching of aluminium from an alloy, containing aluminium and the main metal.

EFFECT: increased activity in the gas-phase reforming of primary spirits and increased stability.

129 cl, 13 tbl, 13 ex

FIELD: chemistry.

SUBSTANCE: invention relates to dehydrogenation or reforming of alcohols, in particular to a method of dehydrogenation of the primary alcohol, such as methanol or ethanol, for obtaining hydrogen, in particular for use in a fuel element with the purpose of obtaining electrical energy. In the method of dehydrogenation a catalyst containing copper is used, which includes a metallic carrier. To solve the given challenge the method includes bringing to contact of the initial raw mixture of the gases containing alcohol, with the catalyst of reforming in order to obtain a mixture of products of reforming, containing hydrogen, and the catalyst for reforming the contains a metallic spongy carrier and a coating on copper, at least, partially covering surface of the given metal spongy carrier where the given metal spongy carrier is obtained by means of the method including the leaching of aluminium from an alloy, containing aluminium and the main metal.

EFFECT: increased activity in the gas-phase reforming of primary spirits and increased stability.

129 cl, 13 tbl, 13 ex

FIELD: chemistry.

SUBSTANCE: invention pertains to the method of obtaining porous substances on a substrate for catalytic applications, to the method of obtaining porous catalysts for decomposition of N2O and their use in decomposing N2O, oxidising ammonia and reforming methane with water vapour. Description is given of the method of obtaining porous substances on a substrate for catalytic applications, in which one or more soluble precursor(s) metal of the active phase is added to a suspension, consisting of an insoluble phase of a substrate in water or an organic solvent. The suspension undergoes wet grinding so as to reduce the size of the particles of the substrate phase to less than 50 mcm. The additive is added, which promotes treatment before or after grinding. A pore-forming substance is added and the suspension, viscosity of which is maintained at 100-5000 cP, undergoes spray drying, is pressed and undergoes thermal treatment so as to remove the pore-forming substance, and is then baked. Description is also given of the method of obtaining porous catalysts on a substrate for decomposing N2O, in which a soluble cobalt precursor is added to a suspension of cerium oxide and an additive, promoting treatment, in water. The suspension is ground to particle size of less than 10 mcm. A pore-forming substance, viscosity of which is regulated to approximately 1000 cP, is added before the suspension undergoes spray drying with subsequent pressing. The pore-forming substance is removed and the product is baked. Description is given of the use of the substances obtained above as catalysts for decomposition of N2O, oxidation of ammonia and reforming of methane with water vapour.

EFFECT: obtaining catalysts with homogenous distribution of active phases and uniform and regulated porosity for optimisation of characteristics in catalytic applications.

FIELD: chemistry.

SUBSTANCE: converter includes housing and devices for input oxygen enriched air, fed of vapour-hydrocarbon mix and bleeding of converted gas. The housing is provided with inner fikking designed as two cylindrical tubes installed one inside the other and forming with the converter housing two radial clearances: the outer clearance for input vapour-hydrocarbon mix and inner one for output of converted gas. At that the packing made of channeled plates is provided for inner fikking, this packing forms the channels of square section; the upper part (1/20-1/25) of channels is provided with perforation track, the middle part (1/5-1/6) of channels height located lower than perforation track is filled with catalyst used for primary and secondary hydrocarbon conversions; and the lowest part (1/6-1/8) of channels height is filled with catalyst used for preliminary hydrocarbon conversion. The device for input oxygen enriched air is positioned in the upper part of channels. The method is implemented in converter. Hydrocarbon material heating and converted gas cooling are carried out by the way of its passing through heat exchanger and mixing of hydrocarbon material with water vapour, then vapour-hydrocarbon mix is fed downstream through outer radial clearance and further it is delivered up the channels through catalyst bed for implementing of preliminary and primary conversions. Then through perforation track it is fed down the channels for converted gas oxidizing and secondary vapour conversion with subsequent converted gas upflow takeoff through inner radial clearance.

EFFECT: increasing of hydrocarbon material conversion and reduction of probability of free carbon formation.

2 cl, 3 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to two methods (two variants) of reforming process using oxidizing gas at temperature 980-1000°C. The recirculation of the flow part outgoing from the autothermic reformer to the flowrate vapour-hydrocarbon is described at that the said recirculation is implemented throught the instrumentality of thermocompressor ejector using heated beforehand supplied mix as operative fluid. For the optimization of general configuration the mole ratio of recirculating synthesis gas and operative fluid was chosen in the range 0.2-1.0. In order to prevent the carbon black formation in the reforming process recirculated hydrogen and vapour are fed to the input flow and the temperature of feeding is increased. Since there is a certain pressure drop between initial mixture of vapour and natural gas and the mix fed to reformer it is necessary to increase the pressure of initial mixture but it is compensated with the lower pressure drop in the heater and other equipment laid out upstream and downstream because of decreasing of vapour capacity.

EFFECT: reforming process is carried out without carbon black formation.

27 cl, 2 dwg, 1 tbl

FIELD: chemistry; processing of hydrocarbon material to synthesis gas.

SUBSTANCE: porous ceramic catalytical module represents the product of exothermic finely dispersed nickel-aluminium mixture exposed to vibration compaction and to sintering. The said product contains: nickel 55.93-96.31 Wt%; aluminium 3.69-44.07 Wt%. Porous ceramic catalytical module may contain up to 20 Wt% (based on the module weight) of titanium carbide as well as catalytic coating including following groups: La and MgO, or Ce and MgO, or La, Ce and MgO, or ZrO2, Y2O3 and MgO, or Pt and MgO, or W2O5 and MgO in quantity 0,002-6 Wt% based on the module weight synthesis gas is produced by conversion of methane and carbon dioxide mixture on porous ceramic catalytical module in filtration mode The process conditions are as follows: temperature 450-700°C, pressure 1-10 atm, rate of CH4-CO2 mixture delivery to catalytical module 500-5000 l/dm3*hr.

EFFECT: inventions permit to carry out the process at lower temperatures.

5 cl, 37 dwg

FIELD: hydrocarbon conversion catalysts.

SUBSTANCE: catalyst for generation of synthesis gas via catalytic conversion of hydrocarbons is a complex composite composed of ceramic matrix and, dispersed throughout the matrix, coarse particles of a material and their aggregates in amounts from 0.5 to 70% by weight. Catalyst comprises system of parallel and/or crossing channels. Dispersed material is selected from rare-earth and transition metal oxides, and mixtures thereof, metals and alloys thereof, period 4 metal carbides, and mixtures thereof, which differ from the matrix in what concerns both composition and structure. Preparation procedure comprises providing homogenous mass containing caking-able ceramic matrix material and material to be dispersed, appropriately shaping the mass, and heat treatment. Material to be dispersed are powders containing metallic aluminum. Homogenous mass is used for impregnation of fibrous and/or woven materials forming on caking system of parallel and/or perpendicularly crossing channels. Before heat treatment, shaped mass is preliminarily treated under hydrothermal conditions.

EFFECT: increased resistance of catalyst to thermal impacts with sufficiently high specific surface and activity retained.

4 cl, 1 tbl, 8 ex

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