Catalytic element for heterogeneous high-temperature reactions
 Method of regeneration of free cyanide from solutions / 2285734Proposed method consists in treatment of waste technological solutions by mineral acid under conditions excluding formation of gaseous hydrocyanic acid followed by separation of phases: solution of hydrocyanic acid and difficultly soluble compounds of elementary cyanides of metals by settling and/or filtration, leaching of clarified solution and re-use of solution of free cyanide thus obtained. Regeneration of free cyanide is carried out directly in solution being treated without conversion of hydrocyanic acid into gaseous phase. |
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N2o decomposition catalyst in ostwald process / 2304465 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. |
 Platinoid mesh catalytic agent / 2294239The 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. |
 Method of intensification of the installation for production of nitric acid / 2286943The 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. |
 Method and the device for supporting of the catalytic meshes in the burners for oxygenation of ammonia / 2284291The 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. |
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Ammonia conversion process / 2276098 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. |
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Method of initiating ammonia conversion reaction / 2253613 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. |
 Catalyst and a method of conversion of ammonia / 2251452The 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. |
 Method of nitric acid production and an installation for production of nitric acid / 2248322The 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. |
 Fischer-tropsch catalyst / 2310508Invention relates to Fischer-Tropsch catalyst containing cobalt and zinc, to a method for preparation thereof, and to Fischer-Tropsch process. Catalyst according to invention containing co-precipitated cobalt and zinc particles, which are characterized by volume-average size below 150 μm and particle size distribution wherein at least 90% of the catalyst particle volume is occupied by particles having size between 0.4 and 2.5 times that of the average particle size and wherein zinc/cobalt atomic ratio within a range of 40 to 0.1. Catalyst is prepared by introducing acid solution containing zinc and cobalt ions at summary concentration 0.1 to 5 mole/L and alkali solution to reactor containing aqueous medium wherein acid solution and alkali solution come into contact with each other in aqueous medium at pH 4-9 (deviating by at most 0.2 pH units) at stirring with a speed determined by supplied power between 1 and 300 kW/L aqueous medium and temperature from 15 to 75°C. Resulting cobalt and zinc-including precipitate separated from aqueous medium, dried, and further treated to produce desired catalyst. Employment of catalyst in Fischer-Tropsch process is likewise described. |
 Exhaust gas treatment catalyst characterized by silica-based support / 2301702Invention relates to catalytic neutralizer for treating internal combustion engine exhausted gases. Proposed catalyst is composed of catalytically active coating on inert ceramic or metallic honeycomb structure, wherein coating contains at least one platinum group metal selected from series including platinum, palladium, rhodium, and iridium on fine-grain supporting oxide material, said supporting oxide material representing essentially nonporous silica-based material including aggregates of essentially spherical primary particles 7 to 60 nm in diameter, while pH of 4% water dispersion of indicated material is below 6. |
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Platinoid mesh catalytic agent / 2294239 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. |
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Catalyst for photo-chemical reactions on base of titanium dioxide and method of production of such catalyst / 2287365 Proposed catalyst is meso-porous titanium-dioxide-based material containing crystalline phase of anatase in the amount no less than 30 mass-% and nickel in the amount no less than 2 mass-%; material has porous structure at average diameter of pores from 2 to 16 nm and specific surface no less than 70 m2/g; as catalyst of photo-chemical reaction of liberation of hydrogen from aqua-alcohol mixtures, it ensures quantum reaction yield from 0.09 to 0.13. Method of production of such catalyst includes introduction of precursor - titanium tetraalkoxyde and template of organic nature, holding reagent mixture till final molding of three-dimensional structure from it at successive stages of forming sol, then gel, separation of reaction product and treatment of this product till removal of template; process is carried out in aqua-alcohol solvent containing no more than 7 mass-% of water; at least one of ligands is introduced into solvent as template; ligand is selected from group of macro-cyclic compounds containing no less than four atoms of oxygen and/or from complexes of said macro-cyclic compounds with ions of metals selected from alkaline or alkaline-earth metals or F-metals containing lithium, potassium, sodium, rubidium, cesium, magnesium, calcium, strontium, barium, lanthanum and cerium; mixture is stirred before forming of sol maintaining its temperature not above 35°C till final molding of three-dimensional structure from reagent mixture; mixture is held in open reservoir at the same temperature at free access of water vapor; after removal of template from three-dimensional structure, mixture is first treated with nickel salt solution during period of time sufficient for withdrawal of nickel ions from solution by pores of structure, after which is it kept in hydrogen-containing medium during period of time sufficient for reduction of nickel ions in pores of structure to metallic nickel. |
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Method for liquid-phase catalytic alkylation of aromatic amines / 2285691 Invention relates to a method for liquid-phase catalytic alkylation of aromatic amines. Method involves alkylation reaction of aromatic amines in the presence of hydrogen and lower alcohols at temperature 50-70°C on a heterogeneous catalyst. The distinctive specificity of method represents alkylation of amine with formaldehyde solution in reactor with reaction zone filled with catalyst consisting of aluminum oxide-base block high-porous cellular carrier with porosity value 7-95%, not less, and palladium as an active component with the mass content = 1.3-2%. As a rule, in the alkylation process catalyst prepared by impregnation of block high-porous cellular carrier with palladium salts treated preliminary in the constant magnetic field is used. Usually, in the case of alkylation of aniline and for preferential synthesis of monomethylaniline the molar ratio aniline to formaldehyde solution = 1.6:(1.1-1.6) is used. Proposed method as compared with the nearest analog in the case of alkylation of aniline provides preparing monomethylaniline mainly, to decrease the content of palladium as an active component in catalyst and to decrease the reaction pressure and hydraulic resistance of catalytic layer also. Invention can be used in producing antiknock additives to motor fuels (gasolines). |
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Method of preparing catalyst for treating internal combustion engine exhaust gases and catalyst prepared by this method / 2275962 Invention relates to a method for preparing catalyst and to catalyst no honeycomb-structure block ceramic and metallic carrier. Preparation procedure includes preliminarily calcining inert honeycomb block carrier and simultaneously applying onto its surface intermediate coating composed of modified alumina and active phase of one or several platinum group metals from water-alcohol suspension containing, wt %: boehmite 15-30, aluminum nitrate 1-2, cerium nitrate 4-8, 25% ammonium hydroxide solution 10-20, one or several precipitate group metal salts (calculated as metals) 0.020-0.052, water-to-alcohol weight ratio being 1:5 to 1:10; drying; and reduction. Thus prepared catalyst has following characteristics: specific coating area 100-200 m2/g, Al2O3 content 5-13%, CeO2 content 0.5-1,3%, active phase (on conversion to platinum group metals) 0.12-0.26%. |
 Fuel-combustion catalyst preparation method (options) / 2275961Method involves preparing porous carrier and forming catalyst layer by impregnation of carrier with aqueous solution of transition group metal salts followed by drying and calcination. Porous catalyst carrier is a porous substrate of organic polymer material: polyurethane or polypropylene, which is dipped into aqueous suspension of powdered metal selected from metals having magnetic susceptibility χ from 3.6·106 to 150·106 Gs·e/g: iron, cobalt, chromium, nickel, or alloys thereof, or vanadium and polyvinylacetate glue as binder until leaving of air from substrate is completed, after which carrier blank is dried at ambient temperature and then fired at 750°C in vacuum oven and caked at 900-1300°C. Caked blank is molded and then subjected to rolling of outside surface to produce carrier having variable-density structure with density maximum located on emitting area. Formation of catalyst layer is achieved by multiple impregnations of the carrier with aqueous solution of acetates or sulfates of transition group metals: iron, cobalt, chromium, nickel, or alloys thereof in alternative order with dryings at ambient temperature and calcinations to produced catalyst bed 50-80 μm in thickness. In another embodiment of invention, formation of catalyst layer on carrier is accomplished by placing carrier in oven followed by forcing transition group metal carbonate vapors into oven for 60-120 min while gradually raising oven temperature to 850°C until layer of catalyst is grown up to its thickness 50-80 μm. |
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Method for preparing epsilon-caprolactam / 2275358 Invention relates to technology for preparing caprolactam by the cyclization reaction of derivatives of aminocaproic acid. Method is carried out by cyclizing hydrolysis of compound chosen from the group comprising aminocaproic acid esters or amides, or their mixtures. The process is carried out in the presence of water, in vapor phase at temperature 200-450°C in the presence of a solid catalyst comprising of aluminum oxide that comprises at least one macroporosity with pores volume corresponding to pores with diameter above 500 Å taken in the concentration 5 ml/100 g of above. Preferably, the specific square of catalyst particles is above 10 m2/g and the total volume of pores is 10 ml/100 g or above wherein pores volume corresponds to pores with diameter above 500 Å is 10 ml/100 g or above. Invention provides improving the process indices due to the improved properties of the solid catalyst. |
 Method of preparing catalyst-containing solid product and device for applying supporting porous material onto inside or outside metallic surface of a hollow body / 2271864Invention relates to supported catalysts and provides a method for preparing catalyst-containing solid product comprising step, wherein ceramic carrier is applied onto metallic surface, and depositing catalytically active material onto ceramic carrier, which was preliminarily coated with supporting porous metallic material, ceramic carrier being applied onto and/or into supporting porous metallic material. Invention also describes device used in preparation of catalyst-containing solid product for applying supporting porous material onto inside or outside metallic surfaces of the hollow body. |
 Reactor with a modular catalyst of a cellular structure / 2265481The invention is pertaining to chemical industry and is used for trapping nitric oxides and other harmful substances from the waste gases. The offered reactor contains a body with the connection pipes for introduction of the initial reactants. Inside the body there is a modular catalyst of a cellular structure. The through channels of the catalyst in respect to the incoming stream are oriented at an angel of 90°. The hydraulic diameter of the through channels of the different geometrical shape, beginning from the first channel, along the stream run is monotonically enlarging, reaching the ratio of the hydraulic diameters of the last channel to the first one first channel of no more than 1.5. No more than 1/6-th of the height from the bottom of the block the modular catalyst of the cellular structure has a mesh-cellular structure with a mesh size from 1.5 up to 3 mm and a specific surface up to 8...10 m2/g. The given engineering solution ensures an increased access to the internal surface of the bottom part of the modular catalyst of the cellular structure and its complete participation in operation. |
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Catalyst for dehydrogenation of olefin and alkylaromatic hydrocarbons / 2308323 Catalyst according to invention is composed of, wt %: potassium and/or lithium, and/or rubidium, and/or cesium compound 5-30, magnesium oxide 0.5-10, cerium(IV) oxide 5-20, calcium carbonate 1-10, molybdenum oxide 0.5-5, ferric oxide - the balance. Catalyst is characterized by loose density at least 1.0 g/cc but not higher than 2.00 g/cc and apparent density at least 2.0 g/cc but not higher than 3.5 g/cc. Starting ferric oxide has loose density 1.0-1.5 g/cc. |
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Catalyst, method of preparation thereof, and a method for dehydrogenation of alkylaromatic compounds / 2302293 Invention relates to production of alkylaromatic hydrocarbon dehydrogenation catalysts and can be employed in chemical and petrochemical industries. Catalyst according to invention comprising molybdenum oxide MoO2, ferrous oxide F2O3, cerium dioxide CeO2, and iron, potassium, calcium , and magnesium compounds is characterized by containing solid solution of potassium ferrites and, additionally, cesium and/or rubidium ferrites MFeO2 and M2Fe10O16, where M=K+Contains and/or Rb, and also ferrite Ca2(MgZn)1Fe2O3 Catalyst may be granulated in the form of trefoil with holes in each foil, which are shifted toward the center of granule, or it may be in the form of circle with three, four, or five internal spokes. Catalyst preparation process and a process of dehydrogenation of alkylaromatic hydrocarbons in presence of indicated catalyst are also described. |
FIELD: inorganic synthesis catalysts.
SUBSTANCE: invention relates to catalytic elements including ceramic contact of regular honeycomb structure for heterogeneous high-temperature reactions, e.g. ammonia conversion, and can be used in production of nitric acid, hydrocyanic acid, and hydroxylamine sulfate. Described is catalytic element for heterogeneous high-temperature reactions comprising two-step catalytic system consisting of ceramic contact of regular honeycomb structure made in the form of at least one bed constituted by (i) separate prisms with honeycomb canals connected by side faces with gap and (ii) platinoid grids, ratio of diameter of unit honeycomb canal to diameter of wire, from which platinoid grids are made, being below 20.
EFFECT: increased degree of conversion and degree of trapping of platinum, and prolonged lifetime of grids.
5 cl, 6 ex
The invention relates to catalytic elements including ceramic contact regular cell structure for high-temperature heterogeneous reactions, for example for the conversion of ammonia, and can be used in the production of nitrogen, hydrocyanic acid, has synthesis.
Known cell catalytic element (Patent RF №2128081, IPC6B01J 35/04, SW 21/26, 1999), which is placed in the reactor vessel for supporting the device in a layer of the individual prisms of the coupled side edges without gaps. This is equivalent to the diameter of the base of the prism and its height are respectively 4-100 and 2-75 equivalent diameters cell channel. In case of using a catalytic element as a catalyst for the conversion of ammonia to the second stage on top of it have a layer of platinum mesh, which is the catalyst for the first stage.
The disadvantage of the catalytic element of the second stage is not sufficiently high conversion in the oxidation of ammonia, oxidative ammonolysis of natural gas
There is a method of conversion of ammonia (RF Patent No. 2223217, IPC7SW 21/26, 2004), including the transmission of the reaction gas mixture through a two-stage catalytic system consisting of a layer of inert nozzles cell structure, the first stage in the form of the platinum layer nets the second stage in the form of a layer of catalyst a regular cell structure. Moreover, the ratio of the equivalent diameter of the channel of the catalyst to the equivalent diameter of the channel inert nozzle is (0,9-1,3):1, the ratio between their open surfaces equal to (0,7-1,2):1.
The disadvantage is not high enough conversion in the oxidation of ammonia and oxidative ammonolysis of natural gas.
The closest technical solution is a catalytic element of the regular cell structure for high-temperature heterogeneous reactions (RF Patent No. 2209117, IPC701J 35/04, 23/745, 23/26, 21/04, SW 21/26, 2003), made in the form of a layer of the individual prisms connected side faces and having a cellular channels, separate prisms when laying them in a layer of the honeycomb structure have a gap between the side faces of 0.1 to 1.0 diameter cell channel.
The disadvantage of this solution is the same as in previous decisions, not high enough conversion in the oxidation of ammonia and oxidative ammonolysis of natural gas.
The problem solved by the present invention is the creation of a catalytic element for high-temperature heterogeneous reactions that reduce the amount of the platinum mesh and increasing the conversion rate of ammonia oxidation to nitric oxide and increasing the conversion rate in the oxidative ammonolysis of natural gas.
The problem is solved using rolled the practical element for high-temperature heterogeneous reactions includes two-stage catalytic system consisting of ceramic contact regular cellular structure made in the form of at least one layer of the individual prisms with cellular channels connected side faces with a gap, and the platinum mesh. The ratio of the diameter of a single cell channel to the diameter of the wire from which made the platinum mesh, has a value less than 20.
A catalytic element for high-temperature heterogeneous reactions preferably has a ceramic contact regular cellular structure, which is made of a material containing porous mullite more than 85 wt.%.
A catalytic element for high-temperature heterogeneous reactions preferably has a ceramic contact regular cell structure, which has the density of mobile channels, which open surface of the ceramic contact does not exceed 30%.
A catalytic element for high-temperature heterogeneous reactions preferably has a gap between the individual prisms more of the diameter of a single cell channel.
A catalytic element for high-temperature heterogeneous reactions preferably contains at least one layer block cordierite sorbent, which come under the layers of ceramic regular contact is th cell structure.
A catalytic element for high-temperature heterogeneous reactions preferably contains under the platinum mesh package woven nets - traps platinum.
A catalytic element for high-temperature heterogeneous reactions preferably has a ceramic contact regular cell structure with a layer height of not more than 10 diameters of the single cell channel.
In the proposed solution to achieve the objectives proposed catalytic element for high-temperature heterogeneous reactions, such as conversion of ammonia, which has a ceramic contact regular cellular structure made in the form of one or more layers of flat prisms having a cylindrical cell channels, separate prisms when laying them in a layer of honeycomb structure are preferably (but the gap can be smaller and to be 0.1-1.0 cell diameter of the channel, depending on the material of the ceramic contact gap of more than one cell diameter of the channel. The height of the flat prism depends on the diameter of the cell channel and preferably not greater than 10 diameters of the single cell channel. The number of flat faces of the prisms varies from three to six. When this side of the base of the prism does not exceed 150 mm Mutually parallel cylindrical channels, subsequently is camping in a checkerboard pattern, create a regular cell structure, the density of the channels should provide an exposed surface of not more than 30%. The diameter of the single cell channel is selected so that the ratio of channel diameter to the diameter of the wire from which are woven or braided mesh, had a value of less than 20. Flat ceramic prisms regular honeycomb structure made of aluminosilicate materials and have a melting point not less than S°. The presence of the material more than 85% of highly porous mullite ceramics gives high resistance to sudden temperature changes in the area of 1000°and provides a warranty period of operation of these products is not less than 10000 hours. To make ceramic prisms catalytic activity in the oxidation of ammonia in the ceramic composition comprises up to 15% of the oxides of copper, silver, cobalt, iron, and in the production of HCN to 0.2% of platinum and palladium. For laying a layer around the perimeter of the contact device are truncated under the diameter of the contact apparatus prism triangular and trapezoidal forms.
In order to reduce losses of platinum oxidation of ammonia is preferably carried out with nets for the capture of platinum and/or cellular ceramic sorbent.
The following examples illustrate the proposed solution
Example 1
In the contact device UKL-7 is and grates stack distribution grid from heat-resistant steel, the layer of ceramic contact regular cell structure from a single rectangular prism with a height of 14 mm and the sides of the base 105×95 mm with a gap of 1.5 mm between the prisms and composition, wt.%: Fe2About3- 8, CuO - 3, the rest of the mullite. For dolldivine around the perimeter of the layer of catalyst blocks are used that have a triangular shape with convex hypotenuse. The radius of convexity of the hypotenuse is 800 mm Diameter single cell channel is 1.4 mm on Top of the catalyst - ceramic prisms - stack package of nine standard woven platinum mesh alloy Plygrd-4-3,5. Wire diameter 0,092 mm diameter single cell channel to the diameter of the wire, which made the platinum mesh is 15,21. The open surface of the ceramic contact regular basis structure is 29%. The operating temperature of the contact apparatus 900-910°C. the Concentration of ammonia in the ABC of 11.5%. The conversion of ammonia to NO 95.5%. The lifetime of the catalytic system 5700 including Irrecoverable losses platinum - 0,129 g/T. the Number of destroyed prisms contact regular cell structure does not exceed 1% of the total number of loaded prisms.
Example 2
In the reactor for the synthesis of hydrogen cyanide stack separating the grid from heat-resistant steel, on which is placed a layer of ceramic contactaremos cellular structure of unit prisms in the form of parallelepipedal height 14 mm, the base is a square with a side of 100 mm, the diameter of the cell channel to 1.4 mm. In aluminosilicate composition of the prisms is 0.2% of platinum. The content in the ceramic phase of mullite 90%. thermal gap between the blocks is 1.5 mm For dolldivine around the perimeter of the layer of catalyst - ceramic prisms are blocks that have a triangular shape with convex hypotenuse. The radius of convexity of the hypotenuse is 600 mm Further layer of catalyst - ceramic prisms - stack four woven platinum mesh alloy Plygrd-4-3,5. The ratio of the diameter of a single cell channel to the diameter of the wire, which made the platinum mesh is 15,21. The open surface of the ceramic contact regular basis structure is 24%. At the operating temperature of 950-1050°and conversion to ammonia 60-65% of the HCN content at the outlet of the reactor is maintained at a level not less than 7.5% over 2500 hours of continuous operation of the contact device. The degree of destruction of the ceramic contact regular cell structure is 3%.
Example 3
In the contact device UKL-7 on the grate stack distribution grid from heat-resistant steel, the block layer cordierite sorbent from a hexagonal prism with a height of 35 mm, the side of the base 36 mm, side triangular cell channel 5 mm, wall thickness of 0.8 mm, Then through the separation jarosch icuu grid on a layer of sorbent is placed a layer of ceramic contact regular cell structure from a single rectangular prism with a height of 14 mm and the sides of the base 105× 95 mm with a gap of 1.5 mm between the prisms and composition, wt.%: Fe2About3- 8, CuO - 3, Co3O4- 2, the rest of the mullite. The diameter of the single cell channel is 1.4 mm To dolldivine on the perimeter of the contact layer and the sorbent used prism having a triangular shape with convex hypotenuse. The radius of convexity of the hypotenuse is 800 mm on Top of the contact stack package of eight knitted platinum mesh alloy Plygrd-4-3,5. Wire diameter 0,076 mm diameter single cell channel to the diameter of the wire, which made the platinum mesh is 18,42. The open surface of the ceramic contact regular cell structure is 29%. The operating temperature of the contact apparatus 885-900°C. the Concentration of ammonia in the ABC of 10.05%. The conversion of ammonia to NO amounted to 95.7%. The lifetime of the catalytic system 5097 h, irretrievable loss of platinum to 0.127 g/T. the Number of destroyed blocks contact regular cell structure does not exceed 1% of the total number of downloaded blocks sorbent 3%.
Example 4
In the contact device UKL-7 on the grate stack distribution grid from heat-resistant steel, the block layer cordierite sorbent from a hexagonal prism with a height of 25 mm side of base 36 mm, side triangular cell channel 5 mm, wall thickness of 0.8 mm. Forth across the separating heat-resistant mesh on a layer of sorbent is placed a layer of ceramic contact regular cell structure, consisting of a single rectangular prism with a height of 14 mm and the sides of the base 105×95 mm with a gap of 1.5 mm between the prisms and composition, wt.%: Fe2O3- 8, CuO - 3, Co3O4- 2, the rest of the mullite. The diameter of the single cell channel is 1.4 mm To dolldivine on the perimeter of the contact layer and the sorbent used prism having a triangular shape with convex hypotenuse. The radius of convexity of the hypotenuse is 750 mm, Top contact stack package of four woven nets-traps (alloy MPE-5, wire diameter 0,092) and eight knitted platinum mesh alloy Plygrd-4-3,5. Wire diameter 0,092 mm diameter single cell channel to the diameter of the wire, which made the platinum mesh is 15,22. The open surface of the ceramic contact regular basis structure is 29%. The operating temperature of the contact apparatus 850-900°C. the Concentration of ammonia in the ABC of 10.05%. The conversion of ammonia to NO was 96.1%. The lifetime of the catalytic system 3200 h, irretrievable loss of platinum - 0,117 g/T. the Number of destroyed prisms contact regular cell structure does not exceed 0.3% of the total number of downloaded blocks sorbent 3%.
Example 5
In the contact device UKL-7 on the grate stack distribution grid from heat-resistant steel, the block layer Cordy is ricovero sorbent from a hexagonal prism with a height of 25 mm, side of the base 36 mm, side triangular cell channel 5 mm, wall thickness of 0.8 mm, Then through the separating heat-resistant mesh on a layer of sorbent is placed a layer of ceramic cell contact from a single rectangular prism with a height of 10 mm and the sides of the base 85×95 mm with a gap of 1.0 mm between the prisms and composition, wt.%: Fe2O3- 11, CuO - 3, Ag2O - 2, the rest is mullite. The diameter of the single cell channel is 1.1 mm For dolldivine on the perimeter of the contact layer and the sorbent used prism having a triangular shape with convex hypotenuse. The radius of convexity of the hypotenuse is 750 mm, Top contact stack package of four woven nets-traps (alloy MPE-5, wire diameter 0,092) and eight knitted platinum mesh alloy Plygrd-4-3,5. Wire diameter 0,076 mm diameter single cell channel to the diameter of the wire, which made the platinum mesh is 14.5. The open surface of the ceramic contact regular cell structure is 22%. The operating temperature of the contact apparatus 850-900°C. the Concentration of ammonia in the ABC of 10.0%. The conversion of ammonia to NO was 96,4%. The lifetime of the catalytic system 3300 h, irretrievable loss of platinum - 0,092 g/T. the Number of destroyed prisms contact regular cell structure does not exceed 0.2% of the t total number of loaded blocks sorbent 2%.
Example 6 (prototype)
In the contact device UKL-7 on the grate stack distribution grid from heat-resistant steel, the block layer of the catalyst for selective oxidation of ammonia to NO composition, wt.%: Fe2O3- 80-85, Cr2O3- 5-10, binder based on Al2O3- other, having a square cross section. The height of the blocks 50 mm side of the block 70 mm, wall thickness 1.5 mm, the size of the channel 5×5 mm clearance between the side faces 5 mm, which is 1.0 in diameter cell channel. For dolldivine around the perimeter of the layer of catalyst blocks are used that have a triangular shape with convex hypotenuse. The radius of convexity of the hypotenuse is 800 mm Above the catalyst stack package of nine standard platinum mesh. The diameter of the wire from which made the platinum mesh is 0,092 mm diameter single cell channel to the diameter of the wire from which made the platinum mesh is 54,34. The operating temperature of the contact apparatus 900-910°C. the Concentration of ammonia in the ammonia-air mixture of 11.5%. The conversion of ammonia to NO was 93.5%. The lifetime of the catalytic system is not less than 4,000 hours with preservation of normal (1.35 g/t) deadweight loss of platinum. The number of destroyed blocks of the catalyst honeycomb structure is % of the total number of downloaded blocks.
As seen from the above examples, when the ratio of the diameter of a single cell channel to the diameter of the wire from which made the platinum mesh, less than 20 proposed catalytic element shows a high degree of conversion in the oxidation of ammonia to nitric oxide, oxidative ammonolysis of natural gas.
Thus, the technical result of the claimed solution is to increase the degree of conversion in the high-temperature heterogeneous reactions, an increase in the degree of recovery of platinum and lifetime platinum mesh.
1. A catalytic element for high-temperature heterogeneous reactions involving two-stage catalytic system consisting of ceramic contact regular cellular structure made in the form of at least one layer of the individual prisms with cellular channels connected side faces with a gap, and the platinum mesh, characterized in that the ratio of the diameter of a single cell channel to the diameter of the wire from which made the platinum mesh, has a value less than 20.
2. A catalytic element for high-temperature heterogeneous reactions according to claim 1, characterized in that the ceramic contact regular honeycomb structure made of a material containing porous mullite more than 85 wt.%.
3. Catalytica the cue element for high-temperature heterogeneous reactions according to claim 1, characterized in that the ceramic contact regular honeycomb structure has a cell density of the channels in which the open surface of the ceramic contact does not exceed 30%.
4. A catalytic element for high-temperature heterogeneous reactions according to claim 1, characterized in that the gap between the individual prisms is more than diameter of a single cell channel.
5. A catalytic element for high-temperature heterogeneous reactions according to claim 1, characterized in that it further comprises at least one layer block cordierite sorbent.
6. A catalytic element for high-temperature heterogeneous reactions according to claim 1, characterized in that under the platinum nets are installing a package from a woven mesh - traps platinum.
7. A catalytic element for high-temperature heterogeneous reactions according to any one of claims 1 to 6, characterized in that the ceramic contact regular honeycomb structure has a height of layer is not more than 10 diameters of the single cell channel.