N2o decomposition catalyst in ostwald process
FIELD: inorganic synthesis catalysts.
SUBSTANCE: decomposition if N2O under Ostwald process conditions at 750-1000°C and pressure 0.9-15 bar is conducted on catalyst, which comprises (A) support composed of α-Al2O3, ZrO2, SeO2, or mixture thereof and (B) supported coating composed of rhodium or rhodium oxide, or mixed Pd-Rh catalyst. Apparatus wherein N2O is decomposed under Ostwald process conditions on the above-defined catalyst is also described. Catalyst is disposed successively downstream of catalyst grids in direction of stream of NH3 to be oxidized.
EFFECT: increased catalyst activity.
8 cl, 2 tbl, 3 ex
The object of the invention is a catalyst for the decomposition of N2O formed as a by-product of the catalytic oxidation of ammonia according to the method of Ostwald.
Catalytic combustion of ammonia to produce nitric acid is known (the way of Ostwald). The combustion of ammonia for large-scale production of NO as the first product of the method is carried out at high temperature (typically between 800 and 950° (C) using, for example, PtRh - or PtRhPd-alloys as catalysts. These catalysts are usually placed in the reactor in the form of woven or knitted meshes in several layers one above the other. To manufacture these nets are usually used wire from PtRh or PtRhPd with a diameter of, for example, 76 microns.
Since the combustion of ammonia noble metal in the form of the oxide is carried away via the gas phase, typically the nets catalysts installing regeneration grids, which are part of the platinum is delayed. In exchange reactions with platinum instead of in the gas phase becomes easier and cheaper palladium.
When getting nitric acid NO formed first on the grids of the catalyst, is subjected to oxidation to NO2. After cooling gas stream is sent to an absorption tower and nitrogen oxides absorb water. Then adding oxygen is prevremeni is with the formation of nitric acid.
As by-products of the combustion of ammonia to form nitrogen and N2O. In contrast, NO and NO2N2O not enter into any further reaction and after passing all stages of the process is displayed in the atmosphere. When using conventional catalytic nets and regeneration grids in the environment derive from 500 to 3000 ppm of N2O, if not conducting any subsequent removal of N2On (EP 1076634 B1).
N2O some time classified as harmful to the climate gas, as it had an adverse effect on the ozone layer and global warming. Because of its potential for global warming is about 300 times larger than that of CO2already a relatively small emission of N2O makes a significant contribution to global warming. As a consequence, try to reduce anthropogenic emissions of N2O.
Thus, the content of N2O in the gas products of the combustion of ammonia should be reduced. This can be achieved either by reducing the formation of N2O, or its decomposition.
For the decomposition of laughing gas have already been proposed several kinds of catalysts. Use and requirements differ depending on whether it is about the purification of waste gases, the destruction of laughing gas from excess gotoblas the CSOs narcotic substances or the removal of ammonia from industrial gaseous wastes. The material of the carrier also has an impact. For example, rhodium (oxide) on gamma-Al2About3has no effect on the reduction of N2O in the process of Ostwald. For catalysts gaseous waste, in contrast, is primarily and preferably use gamma-Al2About3.
For catalysts gaseous waste is known, for example, systems with Pt, Rh, Ru and/or Ir: for example, in Japan patent JP 06142509 for the removal of N2O recommend 0.3 to 2 wt.% Rh on alpha-Al2About3at a temperature of from 300 to 500°C. Also as catalysts there named Ru and Ir. These metals, by contrast, does not act in the process of Ostwald.
In the application JP 6142517 A1 describes deposited on alpha-Al2About3catalyst Rh or Ru and at least one oxide of Ti, Zr, or Nb. It also has a value that EN is not suitable for the process of Ostwald. Next are unsuitable titanium and niobium oxide.
Ru or Pd on SiO2or Al2About3according to the application JP 2002253967 A1 is used for the decomposition of laughing gas, which is in excess as gaseous drugs. The respective reactors are steel tubes that are filled with grains of Al2About3coated with a layer of noble metal, and operated at 150-550°With (application JP 55031463 A1). Here you should also consider according to CNAE requirements due to the fact, what Ru, and Pd did not show any effect in the process of Ostwald and SiO2in the process of Ostwald is not chemically stable. Patent JP 06182203 for the media containing fluorides, for catalysts of noble metals.
According to the application DE 4020914 A1 ammonia burn almost without formation of laughing gas when brought into contact with Pt, Pd, Rh or Ir in combination with at least one oxide of Mo, V However, the described method is not suitable for large scale industrial combustion of ammonia, but only to remove small concentrations of NH3of gaseous waste.
Pure laughing gas may well decompose according to patent DE 3543640 on Pd, caused, for example, corundum, alumina or silicic acid. But palladium is completely inactive to reduce the number of N2In the process of Ostwald.
Specifically for use in the process of Ostwald known, for example, the following systems:
In the application DE 19819882 A1 describes a catalyst for the decomposition of N2O, which is included after the grid of the catalyst and before the heat exchanger and is in the form of a stationary layer. In particular, we are talking about a combination of CuO·Al2About3with tin or lead.
From the application DE 4128629 A1 famous silver catalyst deposited on Al2O3.
According to patent DE 10016276 proposed to talesfore, containing CuO. On an industrial scale was tested, for example, a catalyst based on CuO-Al2O3. Achieved a reduction of 80-90% N2O installing, operating at atmospheric pressure, and about 70% of N2O installation medium pressure (5.5 bar) in Antwerp (G.Kuhn: Proceedings of the Krupp Uhde Technologies Users Group Meeting 2000, Vienna, 12-16 März 2000). NO loss was <0.5 percent. In the publication (Applied Catalysis B: Environmental 44(2003) S.117-151) refer to the fact that copper could be released from the catalyst. Since the decomposition of ammonium nitrate catalyzed by copper, there would be a serious security problem.
According to patent US 2004023796 was developed catalyst for the decomposition of N2O when 250-1000°based spinel oxide With media GeO2(Co3-xMxO4and M represents Fe or Al and x=0-2). NO loss was <0.2 percent. A similar system containing cobalt oxide, also themselves have already been recommended for the oxidation of ammonia (patent EP 0946290 B1).
Patent US 5478549 describes the use of ZrO2as catalyst for the decomposition of N2O. Accordingly this theory in WO 0051715 apply that to the granules ZrO2when receiving can be blended with iron and optimally transition metals.
Mixed oxide catalyst (ZrO2and Al2O3is the subject matter of the application WO 9964139. The catalyst impregn the computerized salt of zirconium, should partially transform N2O (about 15%) NO. N2O have in common to decompose until 78-99%. The required amount of catalyst, however, is very large and, as a rule, requires the reconstruction of the reactor Converter.
Most of these catalysts are characterized by deficiencies that may occur from the point of view of safety, as in the above-described catalyst based on CuO-Al2About3or when conditions in the reactor are insufficiently stable. This applies as catalytically active components, and reinforcing structures, which can have a stabilizing function in relation to the catalytically active.
Therefore there is a need for systems catalysts that effectively removes N2About in the process of Ostwald.
While the catalysts must meet the following requirements.
- Should not kataliziruetsa decomposition of NO, because this would have reduced the effectiveness of the method.
- If we are talking about a stationary catalyst bed, he must have a very high activity and cause only very slight pressure drop at the height of the catalyst layer. Increased pressure loss can also lead to loss of efficiency in obtaining NHO3in particular, if it is impossible far the increase of pressure with available technical devices.
The catalyst should not cause a recalculation of the parameters of the existing Converter.
According to the invention proposes a catalyst comprising rhodium or rhodium oxide, associated with a suitable carrier, which unexpectedly causes a full decomposition of laughing gas, and particularly suitable for so-called FTC-nets (cf DE 19543102 S1). These systems use a multi-layer system without extra grid for regeneration (Catchment traps). Especially preferably the catalyst is in the form of a stationary layer.
As required above, such a catalyst can reduce the number of first primary product of the process of Ostwald - NO. Ceramic materials, such as, for example, alpha-Al2About3that is already in use as mechanical reinforcing material for grids catalysts, as recommended in the patent US 5478549 oxide ZrO2or SEO2consider special reaction conditions are chemically stable. So they can be with advantage used as a carrier of catalysts for the catalyst according to the invention.
The role of rhodium in relation to the N2O technical level assessed rather negatively: research firms OMG showed that the rhodium in the alloy with platinum combustion of ammonia rather induces higher education N2O (Ntrogen & Metanol, No.265, Sept./Okt. 2003, Seiten 45-47).
However, it was unexpectedly found that rhodium or rhodium oxide, deposited on alpha-Al2About3and/or ZrO2, characterized by high catalytic activity concerning decomposition of N2O. in Addition, it was found that mixed palladium-rhodium catalysts can be extremely effectively used for the decomposition of N2O in the process of Ostwald, despite the fact that pure palladium or mixed palladium and Nickel catalysts do not reduce the number of N2O (application US 2003/0124046 A1).
Preferably, if N2O, formed on the grids of the catalyst for combustion of ammonia in adverse reactions and decays through one downstream of the catalyst, and the gas stream is conducted through the catalyst bed located downstream of the flow. Thus the catalyst may be located directly after the nets catalyst or in the case of grids for the regeneration of platinum ("Catchment traps") after these regeneration grids, as described, for example, in patent US 5478549.
The desired operating temperature for the catalyst in the decomposition of N2O, are determined by the operating temperature during the combustion of ammonia. This temperature is not lower than 750°and not more than 1000°for known types of reactors IU the DN 800 and 950° C. the Reactors operate depending on the type of device at a pressure between 1 and 15 bar. The conditions under which the catalytic reaction is the decomposition of N2O, of course, determine very high demands on the material of the catalyst: in case of insufficient chemical resistance, for example, leaching of the catalyst over a long time can lead to the enrichment of the components of the catalyst of the final product (e.g., fertilizers). This could adversely affect their safety in use (risk of explosion by reducing the ignition temperature).
For known catalysts, these requirements are met only in part.
Particularly preferably, the catalyst according to the invention is used in connection with so-called FTC systems (DE 19543102 S1). The use of special alloys and microstructures makes possible a substantial reduction in quantities of expensive noble metals without reducing the efficiency of transformation and the period of validity of the catalyst. Already this has been clearly lower value of N2O in the gas products of the combustion of ammonia compared to a standard catalyst/catcher - grid system. Through combination with a catalyst for the decomposition of N2O according to the invention the value of N2O can be even brennigan. Also significant is the advantage in cost of production FTC systems containing less expensive precious metal.
A very good catalyst was rhodium or rhodium oxide, deposited on alpha-Al2About3or ZrO2. Also has the advantage of combination with palladium: palladium-rhodium on alpha-Al2About3when using as a catalyst N2O in the process of Ostwald leads to a clear reduction of N2O.
Rhodium in the reaction conditions in the reactor downstream of the grids, always oxidized to oxide of rhodium, so the result has a catalytically active component, a rhodium oxide.
Research in real process conditions showed that the material-carriers of alpha-Al2About3and ZrO2coated with rhodium or rhodium oxide, also for a long time retain their catalytic activity. It is also about the media containing both oxide and CEO2separately or together with the aforementioned substances or combinations.
In contrast, for example, rhodium deposited on a gamma-Al2About3located under the mesh catalyst, completely unsuitable for the reduction of N2O. similarly, rhodium or rhodium oxide, deposited on TiO2that proved to be unsuitable for the reduction of N2O when specific conditions about the ECCA Ostwald.
The catalytic activity of rhodium or rhodium oxide, deposited on alpha-Al2About3or ZrO2is so high that the height of the layer of granules of the catalyst reaches 3 cm in order to install medium pressure to reduce the content of N2O below 200 ppm.
If instead of granules using conventional ring process and cover them, for example, a thin surface shell Rh/oxide ceramics, the pressure loss through the system catalysts remains unchanged. But there is a condition that the active membrane before coating Rh calcined at high temperature >900°C, to obtain a stable oxides. This variant of the method is hardly suitable catalysts for gaseous wastes. But in the process of Ostwald this reach unexpectedly high catalytic activity at extremely low pressure loss. This method can also be extended to other media of different geometric shapes.
Also acceptable other well-known media, such as ceramic foam or cellular structure. The next option is the coating of rhodium or a thin surface shell Rh/ZrO2on the grid of the Cantal or megapir (Megapyr) (FeCrAl alloy), often used as a separation between grid nets-catchers. As a dividing grid, and additional the data grid, underneath nets-catchers, can be coated with rhodium or rhodium/active shell and cause an apparent decrease in the number of N2O.
Particularly preferred use of the material according to the invention, if it is used in conjunction with the FTC system. Dividing the grid, which are located between the individual grids FTC can then optionally be equipped with a catalyst and cause an apparent decrease in N2O.
The receipt of the catalyst according to the invention is that protopectin ring process (or grid of Cantal) cover the surface membrane gamma-Al2About3, fired at high temperature (950° (C)to carry out the transformation in alpha-Al2About3and then coated Rh or Pd-Rh or RhxOy. Instead of gamma-Al2About3can also be used a mixture of ZrO2and gamma-Al2About3the same processing as described above. Without this treatment, the catalytic activity is much lower.
The resulting material is suitable as a stationary catalyst layer according to the invention.
Active membrane gamma-Al2About3put in a known manner on the ring process or a grid of Cantal, dried and calcined at 950°With up to a full transformation into alpha-Al2Oz. Yesenia cover Rh or Rh 2O3or PdRh is also a known method.
The extrudate zirconium oxide with a length between 4 and 6 mm and a diameter of about 3.5 mm and the granules of alpha-Al2About3(diameter about 5 mm) is covered by a known method Rh or Rh2O3or PdRh and Pd.
Example 3 (comparative)
The titanium oxide and pellets of gamma-Al2About3with a diameter of 3-5 mm is covered by a known method Rh or PdRh.
The catalysts indicated in examples 1 and 2, tested in the process of Ostwald. The catalysts were located below the grid for the oxidation of ammonia. As a reference system used a conventional system catalyst with a regeneration nets. The process conditions were as follows: temperature = 880°C, pressure = 5 bar abs., download ammonia = 14.5 t NH3/m2/day, the concentration of ammonia = 10,6% vol. in the mixture of the air/ammonia.
The proof of the activity of the claimed catalysts based on noble metals.
1. 0.6% of the noble metal on ZrO2noble metal = 1% Pd, 99% Rh
2. 0.6% of the noble metal on ZrO2noble metal = 30% Pd, 70% Rh
3. 0.6% of the noble metal on ZrO2noble metal = 70% Pd, 30% Rh
4. 0.6% of the noble metal on ZrO2noble metal = 95% Pd, 5% Rh.
The results are given in table 1, 2.
|Catalyst||The conversion of ammonia [%]||The reduction of N2O compared with conventional nets [%]||The height of the layer of granular catalyst [mm]||Example|
|The results of the tests|
|Catalyst||The conversion of ammonia [%]||The reduction of N2O compared with conventional nets [%]||The height of the layer of granular catalyst [mm]|
|0,6% Rh/ZrO2||96||82||30||Example 2|
|Rh2O3/thin surface shell on the rings process||96||80||100||Example 1|
|0,6% Rh/gamma-Al2About3||95||0||22||Example 3|
1. A catalyst for the decomposition of N2O in the process of Ostwald at 750-1000°and 0.9-15 bar, where the catalyst contains
And the media, which consists of alpha-Al2About3, ZrO2SEO2or mixtures thereof, and
In - deposited on the media coverage of rhodium or rhodium oxide, or mixed Pd-Rh catalyst.
2. The use according to claim 1, in which the mixed Pd-Rh catalyst contains from > 0 to 95% Pd.
3. The use according to claim 2, in which the mixed Pd-Rh catalyst contains 30-70% Pd.
4. The use according to claim 1, in which the mixed Pd-Rh catalyst is Pd-Rh alloy.
5. Use one of the preceding paragraphs, where the catalyst is a catalyst stationary layer.
6. Use according to one of claims 1 to 3, where the katal is the blockage is in the form of pellets, Raschig rings, foam or cellular structure.
7. The use according to claim 1, where a is the alpha-Al2About3or Zr2O.
8. Device for the decomposition of N2O in the process of Ostwald, which applies at least one catalyst according to one of claims 1 to 7, which is located sequentially after the grids of the catalyst in the flow direction for the oxidation of NH3.
FIELD: chemical industry; methods of manufacture of the building structures.
SUBSTANCE: the invention is pertaining to the field of the chemical industry, in particular, to production of the nitric acid, nitric fertilizers, the cyanhydric acid, the nitrites and nitrates and to other productions of chemical products, where the flow sheet of production provides for the catalytic conversion of ammonia up to the nitrogen oxides with usage of the platinoid mesh catalytic agents. The platinoid mesh catalytic agent formed in the form of the catalytic package produced out of the layer-by-layer stacked wire catalytic meshes and weaved out of the wires with the diameter of 0.06-0.1 mm consisting of the alloys of platinum with rhodium, palladium, ruthenium and other metals of the platinum group differs that the catalytic package consists of two different in the geometry of the braiding types of the meshes sequentially alternating in the height of the package. At that the geometry of the braiding of the first type of the catalytic meshes is characterized by the number of the wires interlacing per 1 cm2 in the interval of 1024-450, and the geometry of the braiding of the second type of the catalytic meshes is characterized by the number of the wires interlacing per 1 cm2 in the interval of 400-200. The technical result of the invention is the increased conversion of ammonia and the decreased share of the platinoids included in the mesh catalytic agent production processes providing for the catalytic conversion of ammonia in the flow sheet of the chemical goods production.
EFFECT: the invention ensures the increased conversion of ammonia and the decreased share of the platinoids included in the mesh catalytic agent production processes providing for the catalytic conversion of ammonia in the flow sheet of the chemical goods production.
FIELD: chemical industry; method of intensification of the installations for production of the non-concentrated nitric acid.
SUBSTANCE: the invention is pertaining to the method of intensification of the installations for production of the non-concentrated nitric acid and may be used for raising productivity of the installations for production of the non-concentrated nitric acid under pressure. The invention provides for creation of the excess pressure on the inlet of the air compressor by preliminary compression of the atmospheric air in the high-pressure fan. At that the heat of the compression process in the warm season of the year is withdrawn by the direct contact with the water at the inlet of the fan, and in the cold season the heat is used for heating, at that in full or partially excluding heating of the air in the preheater mounted to prevent the icing up of the guiding apparatuses of the air compressor. At the enterprises with the high degree of the air dusting or chemical pollution for the contact cooling of the air by water it is possible to use scrubbers-washers, which combine the functions of the air cooler and the purification device. The method is effective for the operating installations, in which as a result of the wear-out of the flow-through section of the air compressors and the gas turbines decreases not only productivity, but also the pressure in the system, and as the result of it the concentration of the nitric acid. The method allows to realize the intensification of the installations using already existed equipment due to the increased pressure in the system. Concentration of the nitric acid is not lowered, the degree of purification of the tailing gases is preserved, production cost and the specific consumption of the steam and the natural gas are reduced.
EFFECT: the invention allows to realize the intensification of the installations using already existed equipment, to reduce production cost and the specific consumption of the steam and the natural gas.
4 cl, 2 ex, 2 tbl, 2 dwg
FIELD: methods and devices for supporting of the catalytic meshes in the burners for oxygenation of ammonia.
SUBSTANCE: the invention is pertaining to the support system for catalytic meshes in the burners for oxygenation of ammonia and to the method of reduction of movement of the particulates of the ceramic substance caused by the thermal expansion. The support system consists of the catalytic meshes (1) and possibly, of the support sieves (2) which are supported by the ceramic filling agents placed in the burner box with metallic walls and the perforated bottom. The support structure (9) is attached to the metallic wall (4) and-or the outer part of the periphery of the bottom (5). The technical result of the invention is development of the support structure, which does not cause damage of the packet from the catalyzer during operation of the burner, and the development of the system preventing movement of the of the particulates of the ceramic substance.
EFFECT: the invention ensures development of the support structure, which does not cause damage of the packet from the catalyzer during operation of the burner, and the development of the system preventing movement of the of the particulates of the ceramic substance.
12 cl, 2 dwg, 2 tbl
FIELD: inorganic compounds technologies.
SUBSTANCE: invention relates to ammonia conversion processes based on two-step catalytic system, which can be employed in production of nitric and hydrocyanic acids and in hydroxylamine sulfate production. Process according to invention comprises passing gaseous ammonia- and oxygen-containing mixture through two-step catalytic system, wherein first downstream step is embodied in a wire catalytic grate stack and second step in one or several layers of block honeycomb material, ratio of second-step hydraulic resistance value to the first-step one exceeding 4. Catalytic system steps are spaced from each other by distance equal to at most 10 and preferably 0.5 to 2 effective thickness of block channel σ calculated in terms of formula σ=2(S/(πn)1/2 (1-ε1/2), wherein S represents honeycomb block cross-section area, n number of channels in block, and ε open surface of block. Spacing between the steps is achieved by positioning between them spacing layer of gas-permeable chemically inactive material having hydraulic resistance coefficient below 100, hydraulic resistance of the second step being calculated as summary value of hydraulic resistances of honeycomb and spacing layers.
EFFECT: increased yield of desired products.
4 cl, 6 ex
FIELD: initiating ammonia conversion reaction.
SUBSTANCE: proposed method is performed on reticular platinoid catalyst by passing the ammonia-containing gas mixture and oxygen-containing gas through it; local sections of catalyst surfaces are periodically heated to reaction initiating temperature by means of linear electric heating elements located directly on catalyst surface. Equivalent diameters of local sections of catalyst surface are selected between 1-5 of magnitude of external equivalent diameter of separate electric heating element; linear electric heating elements are connected to electric power source at duty factor from 20 to 1 s. Used as material for reticular platinoid catalyst are the following alloys: Pt-81, Pd-15, Rh-3.5 and Ru-0.5 mass-%; Pt-92,5, Pd -4.0 and Rh -3.5 mass-%; Pt-95 and Rh-5 mass-%; Pt-92.5 and Rh-7.5 mass-%. Initiating the ammonia conversion reaction by this method is performed in reactors for production of nitric and hydrocyanic acids and hydroxylamine sulfate.
EFFECT: reduction of time required for reaction over entire surface of catalyst; reduction of explosion danger.
2 cl, 10 ex
FIELD: chemical industry.
SUBSTANCE: the invention is pertinent to the field of chemical industry, in particular to production of a catalysts and processes of oxidation of ammonia in production of a weak nitric acid. The invention offers an ammonia conversion catalyst on the basis of the mixture of oxides of unitized structure and a method oxidation of ammonia in production of weak nitric acid. The catalyst represents a mixture of oxides of the over-all formula (AxByO3Z)k (MmOn)f, (NwPgvOv)r where: A - cation of Ca, Sr, Ba, Mg, Be, Ln or their mixtures; B - cations of Mn, Fe, Ni, Co, Cr, Cu, V, A1 or their mixtures; x=0-2, y=1-2, z=0.8-l.7; M - A1, Si, Zr, Cr, Ln, Mn, Fe, Co, Cu, V, Ca, Sr, Ba, Mg, Be or their mixtures; m=l-3, n=l-2; N - Ti, Al, Si, Zr, Ca, Mg, Ln, W, Mo or their mixtures, P - phosphorus, O - oxygen; w=0-2, g=0-2, v=l-3; k, f and r - mass %, at a ratio (k+f)/r=0-l, f/r=0-l, k/f = 0-100. The catalyst is intended for use in a composition of a two-stage catalytic system generated by different methods, also in a set with the trapping platinoid screens and-or inert nozzles. The technical result ensures activity, selectivity and stability of the catalyst to thermocycles at its use in two-stage catalytic system with a decreased loading of platinoid screens.
EFFECT: the invention ensures high activity, selectivity and stability of the catalyst to thermocycles at its use in two-stage catalytic system with a decreased loading of platinoid screens.
8 cl, 1 tbl, 5 ex
FIELD: chemical industry; production of nitric acid.
SUBSTANCE: the invention is dealt with production of nitric acid with the help of oxidation of ammonia by oxygen of the air and absorption of nitrogen oxides by water in installations with uniform pressure at the stages of oxidation of ammonia and absorption of nitrogen oxides. The method of production of nitric acid in the installations with uniform pressure at the stages of oxidation of ammonia and absorption of nitrogen oxides provides, that compression of the air up to a uniform terminal pressure is conducted continuously within one stage without intermediate cooling and after that the compressed and so heated air is divided into two streams, one of which intended for production of nitric acid is directed to be cooled with further mixing with ammonia, and another is fed directly into a fuel combustion chamber connected with a recuperation turbine. The design embodiment of the installation for production of nitric acid provides for usage in the gas-turbine plant as an air engine for compression of air of an axial-flow compressor mounted directly on a common shaft with the recuperation turbine, at which near the outlet of the air engine the line of a compressed air stream is divided into two parts, one of which intended for production of nitric acid is first connected with a compressed air cooler and then with a mixer of ammonia with air, and the second intended for incineration of fuel is directly connected with the recuperation turbine combustion chamber. Besides in the capacity of a the compressed air cooler they use a "boiling" economizer connected to a line of a feed water for a boiler-utilizer and with a vapor collector of the boiler-utilizer by a line of steam-and-water mixture. The line of the air intended for production of nitric acid is also connected through the reheater of ammonia with a nitric acid blowing column. The technical result is simplification of the method, decreased investments and specific consumption of fuel.
EFFECT: the invention ensures simplification of the method, decreased investments and specific consumption of fuel.
4 cl, 1 dwg
FIELD: chemical industry; methods of manufacture of the deposited polymetallic catalytic agents.
SUBSTANCE: the invention is pertaining to the methods of manufacture of the oxidation catalytic agents based on any solid carriers by deposition on them of the metals solid solutions. The catalytic agents may be used in the various fields of the catalysis, for example, for realization of the photocatalytic, electrocatalytic, catalytic and other reactions. The invention presents the description of the method of manufacture of the deposited polymetallic catalytic agents by deposition of the metals on ceramics, plastics materials, metals, composite materials, oxides of the transition metals, the carbonic material, which includes the sequential stages of deposition of the previous layers carrying the cationic and anionic parts and for recovery. In the capacity of the previous layer carrying the cationic part use the substances of the following composition: [М(NH3)xАy]Вz, where M - Cr, Со, Ni, Cu, Zn, Ru, Rh, Pd, Ag, Cd, Ir, Pt, Au; А - ОН, Н20, C1, Br, I, NO, NO2; В - OH, F, Cl, Br, I, NO2, NO3, SO4; and as the previous layer carrying the anionic part use the substance of the following composition: Еx2[M'Dy2Cz2], where М' - Ti, Cr, Со, Ni, Cu, Zn, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg; С - ОН, Н20, F, SCN, Cl, Br, I, NO, NO2; D - ОН, Н20, F, SCN, Cl, Br, I, NO, NO2; Е - Н, Li, Na, К, Rb, Cs, NH4; or as the previous layer carrying the cationic part use the substances having the following composition: [М(NH3)xАy]Вz and/or [М1(NH3)x1Аy1]Вz1, where M AND M1 - Cr, Со, Ni, Cu, Zn, Ru, Ag, CD, Ir, Pt, Au; А - ОН, Н20, C1, Br, I, NO, NO2; В - OH, F, Cl, Br, I, NO2, NO3, SO4; and as the previous layer carrying the anionic part use the substances having the following composition: Еx2[M'Dy2Cz2] and/or Еx3[M'1Dy3Cz3], where М' and М'1 - Ti, Cr, Со, Ni, Cu, Zn, Zr, Nb, Mo, Tc, Ru, Ag, Cd, Hf, Ta, W, Os, Ir, Pt, Au, Hg; С - ОН, Н20, F, Cl, Br, I, NO, NO2; D - ОН, Н20, F, Cl, Br, I, NO, NO2; Е - Н, Li, Na, К, Rb, Cs, NH4; or as the previous layer carrying both the cationic part and then anionic part use the substance having the following composition: [М(NH3)xАy]x1[M'Dy1Cz1]z, where: M - Cr, Со, Ni, Cu, Zn, Ru, Rh, Pd, Ag, Cd, Ir, Pt, Au; А - ОН, Н20, C1, Br, I, NO, NO2; М' - Ti, Cr, Со, Ni, Cu, Zn, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, Hf, Ta, W, Re, 0s, Ir, Pt, Au, Hg; С - ОН, Н20, F, Cl, Br, I, NO, NO2; D - ОН, Н20, F, Cl, Br, I, NO, NO2. The technical result of the invention is the high activity of the produced catalytic agents.
EFFECT: the invention ensures the high activity of the produced catalytic agents.
14 cl, 3 tbl, 97 ex