Calcination in inert gas in presence of low-concentration oxidising component |
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IPC classes for russian patent Calcination in inert gas in presence of low-concentration oxidising component (RU 2411997):
Method of preparing catalyst carrier and its use in production of catalysts / 2408424
Invention relates to composition intended for producing catalyst carrier, to method of producing said carrier, to catalyst and method of its production, and to method of ethylene oxidation in its presence. Proposed composition comprises the mix of at least one alpha aluminium oxide with mean particle size of about 5 mcm or larger in amount of about 20 wt % to about 40 wt % of total content of aluminium oxide in this composition; at least, one hydrated precursor of alpha aluminium oxide in amount of about 60 wt % to about 80 wt % total content of aluminium oxide in this composition; binder and foaming agent. Invention covers also method of producing catalyst carrier comprising producing above described composition and heating it to convert into porous melted structure, method of producing catalyst comprising deposition of catalytically efficient amount of silver on said catalyst carrier, and catalyst produced as described above. It covers also the method of oxidising ethylene to ethylene oxide comprising gas-phase oxidation of ethylene by molecular oxygen in tubular reactor with stationary layer in the presence of produced catalyst.
 Nanoscale restructuring of aluminium oxide support surface and alkene oxide synthesis catalyst / 2402376
Invention relates to a support, a method of preparing said support, a catalyst for epoxidation of olefins having said support and a method of oxidising ethylene to ethylene oxide. The invention describes a support for a catalyst used in epoxidation of olefins which has an inert heat-resistant solid substrate having a surface and several projections coming out of the surface which are detected at scanning frequencies in the interval from approximately 250 cycles/micrometre or more. Described is a method of making such a carrier involving processing the surface of the substrate in order to obtain several projections on the surface of the substrate. The invention describes a catalyst for epoxidation of olefins having the support described above and a catalytically effective amount of silver, and a method of oxidising ethylene to ethylene oxide using the said catalyst.
Method of making catalyst support / 2395338
Present invention relates to catalysts supports which are used as supports for metal and metal oxide components of catalysts used in different chemical reactions. The invention describes a catalyst support precursor which contains a mixture of alpha aluminium oxide and/or transition aluminium oxide; binder; and a solid sponging agent which expands or releases gas when sufficient heat is supplied. A method of making a catalyst support is described, which involves preparation of the catalyst support precursor described above and water, moulding the obtained precursor into a structure, heating the said structure for a sufficient time and at temperature sufficient for formation of a porous structure as a result of the effect of the sponging agent, and then heating the porous structure for a sufficient time and at temperature sufficient for melting of the porous structure, thereby forming a porous catalyst support. A catalyst preparation method is described, which involves the above described steps for making a porous catalyst support and depositing a catalytically effective amount of silver onto the surface of the support. Described also is a catalyst made using the method described above and a method for oxidising ethylene in the presence of the said catalyst. Described also are catalyst support precursors which contain alpha aluminium oxide and/or transition aluminium oxide, binder, a sponging agent and/or talc or a water-soluble titanium compound, and methods of making the said precursors.
 Method of producing ethylene oxide / 2378264
Invention relates to a method of producing ethylene oxide by bringing a mixture fed into an epoxidation reactor, which may contain ethylene, oxygen, carbon dioxide and water in a defined concentration, into contact with a highly selective epoxidation catalyst containing a promoter amount of rhenium. Contacting the mixture fed into the epoxidation reactor is done under epoxidation reaction conditions at reaction temperature below 260°C. The said mixture contains carbon dioxide in concentration less than 2 mol % of the entire mixture and concentration of water in the mixture of at most 1.5 mol % of the entire mixture. Observation of the combination of the said conditions for carrying out the epoxidation process improves operational properties of the epoxidation catalyst, for example increased stability, selectivity and activity of the catalyst.
 Enhanced carriers from aluminium oxide and silver-based catalysts for producing alkylene oxides / 2372342
Invention relates to methods of producing carriers from aluminium oxide which have desirable properties when used as carriers for silver-based catalysts. The method of making a modified catalyst carrier for vapour-phase epoxidation of alkene involves a) saturation of a moulded carrier made from alpha aluminium oxide, which has been burnt and optionally subjected to other types of processing which provide for preforming, as part of the preforming process with at least one modifier, chosen from silicates of alkali metals and silicates of alkali-earth metals; b) drying said saturated carrier and c) burning said dried carrier at temperature not below 800°C. To obtain the catalyst, the method additionally involves stage d) where silver catalytic material is deposited on the said dried carrier. The invention also relates to epoxidation reactions, carried out in the presence of catalysts given above.
 Method of producing olefin oxide, method of using olefin oxide and catalytic composition / 2361664
Present invention relates to methods of producing a catalytic composition, to the method of producing olefin oxide and method of producing 1,2-diol or 1.2-diol ether. Described is a method of producing a catalytic composition, involving deposition of silver on a carrier and deposition of a promoter - alkali metal on the carrier. The alkali metal contains potassium in amount of at least 10 mcmol/g and lithium in amount of at least 1 mcmol/g in terms of mass of catalytic composition. The alkali metal is deposited on the carrier before depositing silver, at the same time or after depositing silver on the carrier. Described is a method of producing a catalytic composition, involving use of potassium as a promoter in amount of at least 10 mcmol/g and sodium in amount of at least 5 mcmol/g in terms of mass of the catalytic composition. Description is given of a method of producing olefin oxide by reacting olefin, which has at least three carbon atoms, with oxygen in the presence of a catalytic composition, obtained using the method described above. This invention also pertains to the method of producing 1,2-diol or 1,2-diol ether using olefin oxide, obtained using the said method.
 Method of obtaining alkylene oxide using gas-phase promoter system / 2360908
Additive to reaction of epoxidation represents two-component gas-phase promoter system, which contains chlorine-containing component (for instance, ethyl chloride, methyl chloride, vinyl chloride and ethylene dichloride) and nitrogen-containing component from group of nitrogen monoxide and other compounds able to form in reaction conditions at least one gaseous, increasing efficiency, member of pair of oxidation-reduction semi-reaction, including NO, NO2, N2O3 or N2O4. Quantity of each component of said gaseous promoter is taken in such way as to support ratio N* to Z* within the interval from 0.4 to 1, where N* represents equivalent of nitrogen monoxide, in ppmv, ranging from 1 to 20 ppmv, and Z*=(ethyl chloride equivalent (ppmv))x100%/(ethane equivalent (mol %))x100, ranging from 5 to 40 ppmv. Said equivalents are determined depending on concentrations of nitrogen-containing component, chlorine-containing component and ethane or other hydrocarbon at reactor inlet in accordance with stated in i.1 of the formula.
 Catalysts for obtaining alkylene oxides, which have improved stability, efficiency and/or activity / 2360735
Described is catalyst for obtaining alkylene oxide by alkene epoxidation in steam phase, which contains applied by impregnation silver and at least one promoter on burnt heatproof solid carrier, and said carrier contains quantity of zirconium component, which is present in carrier mainly as zirconium silicate, and said heatproof carrier, with the exception of zirconium component at least on 95% by weight consists of aluminium alpha-oxide. Also described is method of said catalyst obtaining which includes: a) mixing of zirconium component, which is mainly present as zirconium silicate, with initial materials of carrier, which include aluminium oxide; b) burning of initial materials of carrier with added zirconium component at temperature less than 1540°C with formation of carrier, which includes aluminium alpha-oxide, where carrier includes zirconium component, present mainly as zirconium silicate; c) further deposition of silver and at least one promoter on carrier. In addition, described is method of catalyst application for alkyl oxide obtaining.
 Method of ethylene oxide production / 2348624
Invention concerns method of ethylene oxide production, involving highly selective epoxidation catalyst including 0.1 to 10 micromol of rhenium per gram of total catalyst weight. Method involves operation of ethylene oxide production system including epoxidation reaction system, ethylene oxide extraction system and carbon dioxide removal system operated in direct connection to each other to ensure ethylene oxide and extraction of ethylene oxide product. To maintain low carbon dioxide concentration in feed mix of epoxidation reactor, major part of gas flow comprising at least 30% to 100%, from ethylene oxide extraction system extracting ethylene oxide from product containing carbon dioxide, is fed to carbon dioxide removal system, which produces gas flow with reduced carbon dioxide content. Gas flow with reduced carbon dioxide content is combined with oxygen and ethylene to obtain feed mix for epoxidation reactor. In addition invention claims method of obtaining 1,2-ethanediene or simple 1,2-ethanediene ether from ethylene oxide, involving obtainment of ethylene oxide by the indicated method.
 Method of obtaining, at least, one product of partial oxidation and/or ammoxidising of propylene / 2347772
Present invention pertains to perfection of the method of obtaining at least, one product of partial oxidation and/or ammoxidising of propylene, chosen from a group, comprising propylene oxide, acrolein, acrylic acid and acrylonitrile. The starting material is raw propane. a) At the first stage, raw propane, in the presence and/or absence of oxygen, is subjected to homogenous and/or heterogeneous catalysed dehydrogenation and/or oxydehydrogenation. Gas mixture 1, containing propane and propylene is obtained. b) If necessary, a certain quantity of the other components in gas mixture 1, obtained in the first stage, besides propane and propylene, such as hydrogen and carbon monoxide is separated and/or converted to other compounds, such as water and carbon dioxide. From gas mixture 1, gas mixture 1' is obtained, containing propane and propylene, as well as other compounds, besides oxygen, propane and propylene. c) At the third stage, gas mixture 1 and/or gas mixture 1' as a component, containing molecular oxygen, of gas mixture 2, is subjected to heterogeneous catalysed partial gas-phase oxidation and/or propylene, contained in gas mixture 1 and/or gas mixture 1', undergoes partial gas-phase ammoxidising. Content of butane-1 in gas mixture 2 is ≤1 vol.%. The method increases output of desired products and efficiency of the process.
Method of improving selectivity of catalyst and a olefin epoxidation process / 2314156
Method of improving selectivity of highly selective epoxidation catalyst on support containing silver in amount at most 0.19 g per 1 m2 of the support surface area comprises bringing catalyst or catalyst precursor containing silver in cationic form into contact with oxygen-containing raw material at catalyst temperature above 250°C over a period of time more than 150 h, after which catalyst temperature is lowered to at most 250°C. Olefin epoxidation process comprises bringing above-described supported catalyst or catalyst precursor into contact with oxygen-containing raw material at catalyst temperature above 250°C over a period of time more than 150 h, after which catalyst temperature is lowered to at most 250°C and catalyst is brought into contact with raw material containing olefin and oxygen.
 Ammonia synthesis catalyst passivation method / 2266788
Passivation of ammonia synthesis catalyst is accomplished via consecutively treating reduced iron catalyst with oxidant at elevated temperatures and process flow rates. Treatment of catalyst with oxidant is commenced with water steam or steam/nitrogen mixture at 150-300°C while further elevating temperature by 50-200°C, after which temperature is lowered to 150-300°C, at which temperature water steam or steam/nitrogen mixture is supplemented by air and treatment of catalyst is continued with resulting mixture while elevating temperature by 50-200°C followed by reduction of catalyst temperature in this mixture to 150-300°C and cooling of catalyst with nitrogen/oxygen mixture at initial ratio not higher than 1:0.1 to temperature 30°C and lower until nitrogen/oxygen mixture gradually achieves pure air composition.
 Method of producing titanium nanocrystalline titanium dioxide-based photocatalyst / 2408428
Invention relates to production of photocatalysts. Proposed method consists in preparing water solution of titanyl sulphate with concentration of 0.1-1.0 mol/l, adding acid thereto obtain concentration of 0.15-1 mol/l, hydrolysis of obtained solution in hydrothermal conditions at 100-250°C for 0.5-24 h, and drying of produced suspension of porous titanium dioxide.
 Method of producing titanium dioxide-based photocatalyst / 2408427
Invention relates to production of photocatalysts. Proposed method consists in preparing water solution of titanyl sulphate with concentration of 0.1-1.0 mol/l, adding acid thereto obtain concentration of 0.15-1 mol/l, hydrolysis of obtained solution in hydrothermal conditions at 100-250°C for 0.5-24 h, and drying of produced suspension of porous titanium dioxide.
Method of preparing catalyst carrier and its use in production of catalysts / 2408424
Invention relates to composition intended for producing catalyst carrier, to method of producing said carrier, to catalyst and method of its production, and to method of ethylene oxidation in its presence. Proposed composition comprises the mix of at least one alpha aluminium oxide with mean particle size of about 5 mcm or larger in amount of about 20 wt % to about 40 wt % of total content of aluminium oxide in this composition; at least, one hydrated precursor of alpha aluminium oxide in amount of about 60 wt % to about 80 wt % total content of aluminium oxide in this composition; binder and foaming agent. Invention covers also method of producing catalyst carrier comprising producing above described composition and heating it to convert into porous melted structure, method of producing catalyst comprising deposition of catalytically efficient amount of silver on said catalyst carrier, and catalyst produced as described above. It covers also the method of oxidising ethylene to ethylene oxide comprising gas-phase oxidation of ethylene by molecular oxygen in tubular reactor with stationary layer in the presence of produced catalyst.
 Sulphur synthesis method and method of preparing sulphur synthesis catalyst / 2405738
Sulphur is obtained via oxidation of hydrogen sulphide contained in gas streams with oxygen or air in a layer with a fixed or fluidised bed of heterogeneous catalyst on a silicon-containing support at 180-320°C in molar ratio oxygen: hydrogen sulphide equal to 0.5-5. The catalyst contains phosphates or fluorides or borates or a mixture of these metal salts selected from: iron, cobalt, nickel, copper or mixture thereof, and contains hydroxyl groups in amount of 0.05-20 mcmol/g. In the first version, powder of the silicon-containing support is pre-treated with phosphoric acid or hydrofluoric acid or boric acid while stirring. Granules are then formed, dried, calcined and saturated with a salt solution of a metal selected from: iron, cobalt, nickel, copper or mixture thereof. In the second version, powder of the silicon-containing support is mixed with a salt solution of a metal selected from: iron, cobalt, nickel, copper or mixture thereof, and then treated with phosphoric or hydrofluoric or boric acid, followed by formation of granules, drying and calcination. In the third version, the silicon-containing support is granulated, dried and calcined, treated with phosphoric or hydrofluoric or boric acid and then saturated with a salt of a metal selected from: iron, cobalt, nickel, copper or mixture thereof and then calcined again.
 Composition based on oxides of zirconium, cerium, lanthanum and yttrium, gadolinium or samarium with high specific surface and reducing ability, method of its production and application as catalyst / 2404855
Invention relates to composition based on oxides of zirconium, cerium, lanthanum and yttrium, gadolinium or samarium with high specific surface and reducing ability, method of its production and application as catalyst for exhaust gas cleaning. Proposed composition consists mainly of oxides of zirconium, cerium, lanthanum and one rare earth metal selected from yttrium, gadolinium or samarium with content of cerium oxide of 20 to 50 wt %, content of lanthanum oxide and oxide the other rare earth metal of 15 to 35 wt %. In case lanthanum oxide content is less than 2 wt %, the composition features specific surfaces of at least 45 m2/g, at least 15 m2/g and at least 7 m2/g, after roasting for 4 h at 1000°C, 10 h at 1150°C and 10 h at 1200°C. Invention covers also the composition consisting of above described oxides and their specific surfaces after roasting at 1000°C and 1150°C. Note here that said composition after roasting at 1150°C exists as pure solid solution and features specific surface after roasting for 10 h at 1200°C of at least 5 m2/g. Invention covers also methods of producing the compositions, catalytic system of exhaust gas purification, method of exhaust gas purification using catalyst of above described composition or catalytic system.
 Compound containing multimetal complex, metal complex and method of their production, method of producing catalyst for exgaust gas purification that uses said complexes / 2403086
Invention relates to compound that represents a multimetal complex comprising assemblage of metal complexes wherein ligand is coordinated by one metal atom or assemblage of atoms of one metal. Note here that assemblage of metal complexes are bound together by polydentant ligand which substitutes partially the ligands of metal complex assemblage and contains 2 to 1000 ligand atoms wherein each metal complex has carboxylic ligand and aforesaid polydentant ligand that represents dicarboxylic acid ligand, while metal is selected from the group consisting of Pt, Ni or Pd. Invention covers also the method of producing clusters of metal or metal oxide, the method of producing compound containing multimetal complex, and metal complex.
 Carbon-bearing material combustion catalyst, method of preparing said catalyst, catalyst support and preparation method thereof / 2401698
Present invention relates to a combustion catalyst for combustion and removal of carbon-bearing material, to a method of preparing said catalyst, to a catalyst support and preparation method thereof. The method of preparing the carbon-bearing material combustion catalyst involves steps for mixing, drying and burning. At the mixing step, zeolite, except sodalite, and an alkali metal source and/or alkali-earth metal source are mixed in a polar solvent such as water or another in a defined ratio. At the drying step after mixing, the liquid mixture is heated with evaporation of water in order to obtain a solid substance. At the burning step, the substance is burnt at temperature of 600°C or higher to obtain a carbon-bearing material combustion catalyst. The invention describes a method of preparing a support for the carbon-bearing material combustion catalyst on a ceramic substrate, whereby the catalyst support is designed for combustion of carbon-bearing material contained in exhaust gas of an internal combustion engine, involving attaching the combustion catalyst made using the described method onto a ceramic substrate and a catalyst support made using this method.
 Carbon-bearing material combustion catalyst, method of preparing said catalyst, catalyst support and preparation method thereof / 2401697
Invention relates to a catalyst for combustion of carbon-bearing material contained in exhaust gas of an internal combustion engine, to a method of preparing said catalyst, as well as a support for said catalyst and method of preparing said support. The invention describes a method of preparing a carbon-bearing material combustion catalyst which is attached to a ceramic substrate, involving mixing aluminium silicate having atomic equivalent ratio Si/Al≥1 and an alkali and/or alkali-earth metal source in a polar solvent such as water or another, drying the liquid mixture to obtain a solid substance and burning it at temperature of 600°C or higher. The aluminium silicate is sodalite. Alternatively, the carbon-bearing material combustion catalyst is prepared through a sequence of steps for mixing, drying and burning, whereby the method involves burning sodalite at temperature of 600°C or higher. A catalyst prepared using the method given above is described. Described also is a method of preparing a catalyst support involving a step for attaching the combustion catalyst to a ceramic substrate, and a catalyst support made using said method.
 Composition base on oxides of zirconium, cerium, yttrium, lanthanum and other rare-earth metals, method of its production and use in catalysis / 2398629
Proposed invention relates to catalyst composition and can be used for treatment of, for example ICE exhaust gases. Composition based on zirconium oxide with concentration equal at least 25% comprises, in % by wt: 15 to 60 of cerium oxide, 10 to 25 yttrium oxide, 2 to 10 of lanthanum oxide and 2 to 15 of oxide of the other rare-earth metal Besides said composition, after incineration for 10 h at 1150°C, features specific surface equal to at least 15 m2/g, and crystalline phase with cubic lattice. Composition results from formation of the mix containing compounds of zirconium, cerium, yttrium, lanthanum and additional rare-earth element, extraction of sediment from said mix with the help of base, heating said sediment in water, adding surfactant to sediment and its incineration. This composition can be used as a catalyst.
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FIELD: chemistry. SUBSTANCE: invention relates to an improved method of producing silver catalysts used in gas phase synthesis of ethylene oxide from ethylene and oxygen. Described is a method of producing a catalyst, involving saturation of an inert substrate with a solution which contains a catalytically effective amount of a compound which contains silver, a promoting amount of a compound which contains a transition metal, calcination of the saturated substrate by heating at temperature ranging from approximately 200°C to approximately 600°C for a period of time sufficient for reducing the silver compound to metallic silver, and for decomposition and removal of almost all organic substances; heating is carried out in an atmosphere which includes a combination of an inert gas and from approximately 10 parts per million to approximately 500 parts per million of a gas which contains an oxygen-containing oxidising component. The invention describes a catalyst produced using said method, and a method of oxidising ethylene to ethylene oxide using molecular oxygen in gaseous phase in the presence of the obtained catalyst in a fixed layer in a tubular reactor. EFFECT: improved catalyst activity and selectivity. 25 cl, 1 ex, 1 dwg
The prior art inventions The technical field to which the invention relates This invention relates to an improved silver catalyst useful in the production of oxides of alkylene, their reception and their use in methods of oxidation alkylene. More specifically the invention relates to the preparation of silver catalysts on the substrate, promoted by metal capable of oxidation of alkene, preferably ethylene, a gas containing oxygen, in the gas phase for the production of oxide alkylene, preferably ethylene oxide, with high efficiencies and selectively. Description of the prior art In this area it is known the production of a silver catalyst on a substrate for the conversion of ethylene and oxygen to ethylene oxide. To improve the activity and selectivity of these catalysts was proposed many modifications. These modifications included the improvement of the used substrates, methods of production, the physical condition of silver on the substrate and the inclusion in the composition of catalyst additives. Known methods for producing silver catalysts on the substrate, useful for the oxidation of ethylene to ethylene oxide in the gas phase, which include the impregnation of the substrate, such as alumina, with a solution of silver salt/amine.U.S. patent 3702359 predstavljaet an illustration of such methods. In U.S. patent 2125333 discloses the use of alkali metals such as sodium and potassium, and their salts as additives for various silver catalysts used for ethylene oxide. In U.S. patent 2615900 contains a lot of useful promoters. In U.S. patent 2773844 disclosed multi-stage method of applying silver. In U.S. patent 3575888 disclosed the use of substrates of alumina having a pore volume from about 0.15 to 0.30 m2/g and a surface area below about 10 m2/year In U.S. patent 3962136 and 4010115 was marked by the use of alkali metals K, Rb and Cs in small quantities as a useful promoters for silver catalysts on the substrate. In U.S. patent 4005049 specified receipt of the catalyst comprising the silver/transition metal useful in oxidation reactions. According to the U.S. patent 4536482 catalytically active metals such as Ag and Re, sprayed together along with the material for the co-deposition on a specific substrate. Getting a similar way silver catalysts which also contain promoters - alkali metals, see, for example, in U.S. patent 3962136. Such methods of obtaining silver catalysts promoted with alkali metal and rhenium and also additional promoter selected from sulfur, molybdenum, tungsten is, chromium and mixtures presented in U.S. patent 4766105. Obtaining catalysts using the methods of the previous prior art includes the impregnation of the substrate with a solution of silver/amine, which may contain various promoters, and then heating the impregnated substrate in the chamber with forced air at a temperature of 275°C for recovery of silver to metallic silver and to separate volatile components from the catalyst. In U.S. patent 4916243 presents silver catalysts for the oxidation of ethylene to ethylene oxide by impregnation of the inert substrate solutions of silver/amine and silver lactate. Then the impregnated carriers were processed by heating on a steel strip passing through the zone heat 2"×2" for 2.5 minutes, the temperature zone heating was maintained at 500°C. by passing hot air upward flow through the tape or 400°C for 4 minutes. U.S. patent 5444034 relates to the preparation of a silver catalyst, wherein the substrate is impregnated with a solution of a hydrocarbon-based silver salt of organic acid and activate Paladino at a temperature of not more than 500°C in an inert gas, such as nitrogen. In other descriptions, the method of production of ethylene oxide, the addition of oxygen-containing gases in the feed material has led to an increase in efficiency is Yunosti. For example, in U.S. patent 5112795 to the composition of the injected gas: 8% vol. oxygen, 30% vol. ethylene, about 5 MSK of ethylchloride and the remainder nitrogen, was added 5 hours per million of nitric oxide. According to other ways to increase efficiency, particularly selectivity, the catalyst is subjected to treatment at a specific temperature and a specific gas mixture. For example, in the publications US 2004/0049061 and 2004/002954 selectivity of the catalyst is highly selective epoxidation can be improved by treatment with a heated catalyst in the presence of oxygen at a temperature which is usually higher than normal initial operating temperature of the catalyst. In U.S. patent 5504052 and 5646087 presents silver catalysts for the oxidation of ethylene to ethylene oxide, obtained by impregnation of the inert substrate with a solution of silver/amine, and various promoters and calcining the impregnated substrate at 300-500°C, and the catalyst was kept in an inert atmosphere. Thus, according to prior art catalyst obtained by calcining the impregnated substrate or on the air, i.e. in the presence of large quantities of oxygen or in an inert atmosphere, such as nitrogen. Surprisingly, it was found that the calcination of the impregnated substrate in an inert atmosphere, such as nitrogen, adding only sky is logo amount of gas-oxidant, such as molecular oxygen, in an inert atmosphere increases the service life, improve the activity and selectivity of the catalyst to ethylene oxide. Brief description of the invention According to the invention features a method of producing a catalyst useful for the production of ethylene oxide from ethylene and oxygen in the gas phase, which includes the impregnation of the inert substrate with a solution containing a catalytically effective amount of compounds containing silver, a promoting amount of a component containing alkali metal and a promoting amount of a compound containing a transition metal; calcining the impregnated substrate by heating the impregnated substrate at a temperature of from about 200°to about 600°C for a period of time sufficient for recovery of silver compounds containing silver to metallic silver and to decompose and remove mostly all organic substances; a heat conducting in the atmosphere, comprising the combination of inert gas and from about 10 h/m to about 5% vol. gas that includes oxygen containing oxidizing component. Also according to the invention features a method of producing a catalyst useful for the production of ethylene oxide from ethylene and oxygen in the gas phase is, which includes the impregnation of the inert substrate with a solution containing a catalytically effective amount of compounds containing silver, a promoting amount of a compound containing alkali metal and a promoting amount of a compound containing a transition metal; calcining the impregnated substrate by heating the impregnated substrate at a temperature of from about 200°to about 600°C for a period of time sufficient for recovery of silver compounds containing silver to metallic silver and to decompose and remove mostly all organic substances; the heating is carried out in an atmosphere comprising a combination of inert gas and from about 10 h/m to approximately 1% vol. gas that includes oxygen containing oxidizing component. In addition, according to the invention features a method of producing a catalyst useful for the production of ethylene oxide from ethylene and oxygen in the gas phase, which includes the impregnation of the inert substrate with a solution containing a catalytically effective amount of compounds containing silver, a promoting amount of a compound containing alkali metal and a promoting amount of a compound containing a transition metal; calcining the impregnated substrate by heating the impregnated substrate PR is a temperature of from about 200°to about 600°C for a period of time, sufficient for the recovery of silver compounds containing silver to metallic silver and to decompose and remove mostly all organic substances; the heating is carried out in an atmosphere comprising a combination of inert gas and from about 10 h/m to about 500 hours/million gas comprising oxygen containing oxidizing component. In addition, according to the invention proposes a method of oxidation of ethylene to ethylene oxide, which involves the oxidation of ethylene to ethylene oxide by molecular oxygen in the gas phase in the presence of the above catalyst in a fixed bed in a tubular reactor. Brief description of drawings The drawing is a curve describing the dependence of selectivity on time for the catalyst calcined at (A) pure nitrogen (No) in nitrogen with the addition of a small amount of oxygen, and (C) in air for the catalysts of example. Detailed description of the invention The catalysts according to the invention is obtained by impregnation of a porous heat-resistant substrate by silver ions, compounds, complex compounds and/or salts, dissolved in a suitable solvent, sufficient for applying connection-predecessor of silver on the substrate. Then the impregnated carrier is removed from the solution, and caused the connection with the ribs reduced to metallic silver by high-temperature annealing. Also on the substrate simultaneously with the application of silver or pre-applied suitable ions, compounds and/or alkali metal salts, dissolved in a suitable solvent. Also on the substrate simultaneously with applying silver and/or alkali metal or previously or subsequently applied suitable transition metals in the form of ions, compounds, complex compounds and/or salts dissolved in an acceptable solvent. The applied substrate or carrier, are useful for these catalysts, can be a porous refractory carrier or the material for the substrate of the catalyst that is relatively inert in the presence of supplied materials for the oxidation of ethylene, products and reaction conditions. Such conventional materials well known to the experts, qualified in this field, can be of natural or synthetic origin and preferably are of a macroporous structure, which means that the structure has a surface area of approximately 10 m2/g or less, and preferably approximately 3 m2/g or less. Examples of substrates which are useful as substrates for catalysts for production of ethylene oxide according to the invention are the oxides of aluminum, in particular aluminum oxide, activated carbon, pumice, mA who nesia, Zirconia, kieselguhr, mullerova earth, silicon carbide, porous agglomerates comprising silicon oxide and/or silicon carbide, silicon oxide, magnesia, some clays, artificial and natural zeolites and ceramic materials. Preferred catalysts can be produced using substrates, including aluminum oxide, silicon oxide, silicates or combinations thereof. The most preferred substrate mainly containing silicates, specifically contain up to about 15% wt. oxide of silicon. In the case of substrates containing corundum, preferred are having a surface area measured by the BET method, of from about 0.03 m2/g to about 10 m2/g, preferably from approximately 0.05 m2/g to about 5 m2/g, more preferably from about 0.1 m2/g to about 3 m2/g and pore volume of water measured by the conventional method of water absorption is from about 0.1 cm3/g to about 0.75 cm3/g by volume, preferably from about 0.25 cm3/g to approximately 0,55 cm3/, BET Method for the determination of the specific surface area is described in Brunauer, S., Emmett, P.H. and Teller, E., J. Am. Chem. Soc., 60, 309-16 (1938). Pore volume and pore dimensions define a common method used is of mercury porosimetry; see Drake and Ritter, “Ind. Eng. Chem. Anal. Ed.,” 17, 787 (1945). Such carriers are commercially available in the Norton Company. For commercial use in the production of ethylene oxide optionally, the substrate is formed into the shape of pellets, spheres, rings, grains, fragments, pieces of,cart wheels and of such a size suitable for use in reactors with a fixed layer. If desired, particles of the substrate can have "equivalent diameters in the range from approximately 3 mm to approximately 10 mm, and preferably from about 4 to about 8 mm, which are usually compatible with the internal diameter of the tube reactor in which the catalyst. "Equivalent diameter" is a diameter of a sphere having the same ratio of surface area (i.e. neglecting surface within the pores of the particles) to the volume that used particles of the substrate. Standard porous heat-resistant substrate, as described above, is impregnated with a solution for impregnation, containing silver, preferably an aqueous solution containing silver. The substrate is impregnated simultaneously or at separate stages of different promoters for the catalyst. Preferred catalysts obtained according to this invention contain up to about 45% wt. silver is applied in the form of metal on the surface and throughout the horses then, the porous heat-resistant substrate. Preferred are silver content in the form of metal approximately 1-40% relative to the total weight of the catalyst, in addition, the silver content 8-35% are more preferred. The amount of silver deposited on the substrate or on the substrate, is the amount which is catalytically effective amount of silver, i.e. the amount that the best way catalyzes the interaction of ethylene and oxygen with production of ethylene oxide. Used in the description, the term "catalytically effective amount of silver" refers to the amount of silver, which provides a measurable degree of conversion of ethylene and oxygen to ethylene oxide, as well as the selectivity, activity and stability over the life of the catalyst. Useful, but not the only compounds containing silver are silver oxalate, silver nitrate, silver oxide, silver carbonate, silver carboxylate, silver citrate, phthalate, silver, silver lactate, propionate, silver butyrate and silver salts of higher fatty acids and their combinations. This catalyst comprises silver in a catalytically effective amount of alkali metal in the promoting amount of the transition metal in the promoting amount deposited on a porous heat-resistant substrate. Used opisanie the term "promoting amount" of a particular component of the catalyst refers to the amount of the component which effectively improves one or more of the catalytic properties of this catalyst compared to a catalyst not containing the specified component. Used the exact concentration along with other factors, of course, will depend on the desired silver content, the nature of the substrate, the viscosity of the liquid and the solubility of compounds containing silver. In addition to the silver catalyst also contains the promoter of an alkali metal selected from lithium, sodium, potassium, rubidium, cesium or combinations thereof, preferred is cesium. The amount of alkali metal deposited on a substrate or catalyst or present on the substrate or the catalyst should be promoting. Preferably the amount will vary from approximately 10 hours per million to about 3000 hours per million, more preferably from about 15 hours/million to approximately 2000 hours/million, even more preferably from approximately 20 hours/million to approximately 1500 h/m and even more preferably from approximately 50 hours per million to about 1000 hours/million by weight, measured metal relative to the total weight of the catalyst. The catalyst also contains the promoter of the transition metal, which includes an element of groups 5b, 6b, 7b and 8 of the periodic table of elements and combinations thereof. Preferably the transition metal on the em element, selected from the group 7b of the periodic table of elements. Preferred transition metals are rhenium, molybdenum and tungsten, the most preferred are molybdenum and rhenium. The number of transition metal promoter deposited on a substrate or catalyst or present on the substrate or the catalyst should be promoting. The promoter of the transition metal may be present in an amount, calculated as the metal, from about 0.1 micromoles per gram to about 10 micromoles per gram, preferably from about 0.2 micromoles per gram to about 5 micromoles per gram, and more preferably from about 0.5 micromoles per gram to about 4 micromoles per gram. The solution containing silver is used for impregnation of the substrate may also include additional solvent or complexing/solubilizers agent, known to specialists in this field. You can use a wide range of solvent or complexing/solubilizing agents for dissolution of silver in the environment for impregnation in the desired concentration. Useful complexing/solubilizing agents include amines, ammonia and lactic acid, and combinations thereof. Amines include alkylenediamine having from 1 to 5 carbon atoms is. In one preferred embodiment, the solution includes an aqueous solution of silver oxalate and ethylene diamine. Complexing/solubilizers agent may be in solution for impregnation in the amount of from about 0.1 to about 5.0 moles of Ethylenediamine per mole of silver, preferably from about 0.2 mol to about 4.0 mol and more preferably from about 0.3 mole to about 3.0 moles of Ethylenediamine per mole of silver. In the case of using the solvent, it can be water based or organic based and can be polar or substantially or completely non-polar. In General, the solvent should be sufficient solutious force to solubilisation components of the solution. At the same time, it is preferable that the solvent was selected to avoid undesirable effects or interactions with solvated by the promoters. Examples of solvents for the organic base include, but are not limited to, alcohols, particularly alkanols, glycols, specifically alkylphenol, ketones, aldehydes, amines, tetrahydrofuran, nitrobenzene, nitrotoluene, methyl esters of ethylene glycol, specifically onomatology ether of ethylene glycol, diethyl ether of ethylene glycol and tetraethyl ester of ethylene glycol and the like. Solvents on an organic basis, the cat is which have from 1 to about 8 carbon atoms per molecule, are preferred. You can use a mixture of organic solvents or water and one or more organic solvents, provided that such mixed solvents act as required according to the description. The salt concentration of silver in the solution is in the range from about 0.1% wt. to the maximum when the solubility of the specific combination of salt/solubilizing agent. Mostly very suitable for applications are solutions of silver salts containing from 0.5% to about 45% wt. silver, and preferred are silver concentration from 5 to 30% wt. Impregnation of the selected substrate spend the conventional methods of impregnation in excess of the solution for impregnation,impregnated to saturation, etc. Typically, the substrate material is kept in the solution containing silver until a sufficient amount of solution is not absorbed by the substrate. Preferably the amount of the solution containing silver used for impregnation of the porous substrate does not exceed the amount necessary to fill the pores of the porous substrate. The liquid containing the silver penetrates into the pores of the substrate by absorption, under the action of capillary forces and/or under a vacuum. It is possible to carry out a single impregnation or series of impregnations with or without erotichnoe drying partly depending on the salt concentration of silver in solution. Methods of impregnation are disclosed in U.S. patents 4761394, 4766105m, 4908343, 5057481, 5187140, 5102848, 5011807, 5099041 and 5407888, which are included in the description by reference. Perhaps the use of previously known methods prior to the application of,the joint application and the subsequent application for different promoters. Examples of catalytic properties include, in particular, the suitability (robust operation in the operation mode), selectivity, activity, turning ability, stability and productivity. Specialist qualified in this area, it should be clear that one or more individual catalytic properties can be improved in the presence of "promoting amount", while other catalytic properties can be improved, or can be improved, or can even be weakened. In addition, it is clear that different catalytic properties can be improved under different operating conditions. For example, it is possible to operate the catalyst having improved selectivity for one set of operating conditions, with a different set of conditions under which, instead of improvement in activity is detected improvement in selectivity, and the operator of the plant for production of ethylene oxide can intentionally change the operating conditions to improve specific catalytic t is in even at the expense of other catalytic properties to optimize conditions and results taking into account the cost of maintaining inventory, energy consumption, costs for removal of by-products and the like. The particular combination of compounds containing silver, substrate, alkali metal promoter and promoter transition metal according to the current invention will provide an improvement in one or more catalytic properties compared with the same combination of silver and the substrate and in the absence or in the presence of only one promoter. After impregnation, the substrate is soaked in connection predecessor of silver and promoters, is subjected to calcination or activate during a period of time sufficient to recover the component of silver to metallic silver and to remove the volatile products of decomposition of the substrate, containing silver. The calcination is conducted by heating the impregnated substrate preferably with a gradual temperature increase to a temperature in the range of from about 200°C to 600°C, preferably from about 250°C to 500°C and more preferably from about 300°C to 450°C at pressures of interaction in the range of from 0.5 to 35 bar over a period of time sufficient to convert the retained silver in metallic silver or decomposition of all or almost all present the organic materials and remove them in view of the volatile components. Useful periods of time of heating may vary from about 1 minute to 12 hours, preferably from about 2 minutes to about 6 hours, and more preferably from about 2 minutes to about 1 hour. Basically when a higher temperature is required for restoration periods. For heat treatment of the impregnated substrate was wide interval periods of heating (for example, in U.S. patent No. 3563914 offered to hold the heat in less than 300 seconds, in U.S. patent No. 3702259 disclosed heating from 2 to 8 hours at a temperature of from 100°C to 375°C for recovery of silver in the composition of the salt in the catalyst, and in U.S. patent No. 3962136 was proposed from 1/2 to 8 hours in the same temperature range), it is important that the recovery time correlates with temperature in such a way that is almost a complete transformation of silver salts in a catalytically active metal. For this purpose you can use continuous or stepwise program of heating. According to this invention by heating the impregnated substrate is kept in an atmosphere with a combination of inert gas and from about 10 h/m to about 5% vol. gas that includes oxygen containing oxidizing component. For purposes of this invention, an inert gas op is edalat generally do not interact with components forming catalyst under conditions selected to obtain a catalyst. It includes nitrogen, argon, krypton, helium and combinations thereof, and the preferred inert gas is nitrogen. The gas including the oxygen containing oxidizing component may include molecular oxygen, CO2, NO, NO2N2O3N2O4or N2O5or substance, under conditions capable of annealing to the formation of NO, NO2N2O3N2O4and N2O5or combinations thereof, and optionally include SO3, SO2P2O5P2O3or combinations thereof. Preferred of these gases is molecular oxygen, and more preferred is a combination Of2with NO or NO2. According to a useful embodiment, the atmosphere comprises from about 10 h/m to approximately 1% vol. gas that includes oxygen containing oxidizing component. According to another useful embodiment, the atmosphere comprises from about 50 h/m to about 500 hours/million gas comprising oxygen containing oxidizing component. The production of ethylene oxide Basically the processes of production of ethylene oxide applied on an industrial scale, are continuous interaction of the gas containing oxygen with ethylene in the presence of a real what about the catalyst at a temperature in the range of from about 180°to about 330°C. preferably from about 200°to about 325°C., more preferably from about 225°to about 270°C at a pressure which may vary from about atmospheric pressure to about 30 atmospheres, depending on the mass flow rate and the desired productivity. Generally use a pressure in the range of from about atmospheric to about 500 lb/in2. However, according to the scope of the invention it is possible to use higher pressures. The residence time in the reactor of large scale mainly 0.1-5 seconds. Oxygen can be introduced into the interaction in the stream containing oxygen, such as air or oxygen from a commercially available source of supply, such as a reservoir. The obtained ethylene oxide is separated and isolated from the products of interaction using conventional methods. However, according to this invention in the process of ethylene oxide is provided by conventional gas recycling, including the recycling of carbon dioxide in normal concentrations, for example from about 0.5 to 6 percent by volume. The normal process of oxidation of ethylene to ethylene oxide involves the oxidation of ethylene with molecular oxygen in the gas phase in the presence of a catalyst in a fixed bed in Proc. of Batam reactor. Conventional commercially available reactor with a fixed bed ethylene oxide usually in the form of multiple parallel long tubes (in a suitable enclosure)filled with catalyst, from about 0.7 to 2.7 inch OD and from 0.5 to 2.5 inch internal Affairs and 15-45 feet in length. It was shown that the catalysts according to the invention should be particularly selective catalysts for the oxidation of ethylene with molecular oxygen to ethylene oxide. The terms of such oxidation reactions in the presence of the catalyst according to the present invention, in General, include the conditions described for the prior art. This applies, for example, to suitable temperatures, pressures, residence time, compounds, diluents, such as nitrogen, carbon dioxide, water vapor, argon, methane or other suitable hydrocarbons, the presence or absence of retarding agents to control the catalytic action, for example 1,2-dichloroethane, vinyl chloride or chlorinated compounds of polivinil desired application operations recirculatory or subsequent conversion in different reactors to increase yield of ethylene oxide and any other special conditions that can be selected for the process of ethylene oxide. Used as Rea is enta molecular oxygen can be obtained from conventional sources. Suitable for supply of oxygen may represent a relatively pure oxygen, concentrated oxygen flow that includes a large amount of oxygen with lesser amounts of one or more diluents, such as nitrogen, argon, etc. or another oxygen-containing stream such as air. The use of these catalysts in the oxidation of ethylene in no way limited to use in specific conditions, which are known to be effective. The obtained ethylene oxide is separated and recovered from the reaction products by using common methods known and used in the field. The use of the silver catalysts of the invention in the production process of ethylene oxide provides in General a higher selectivity for the oxidation of ethylene to ethylene oxide at a given conversion of ethylene than possible with conventional catalysts. In the production of ethylene oxide mixture supplied reagents may contain from 0.5 to 45% ethylene and from 3 to 15% oxygen, and the remaining part consists of relatively inert materials, including substances such as nitrogen, carbon dioxide, methane, ethane, argon and the like. Preferably the application of the silver catalysts of the invention for obtaining ethylene oxide with the oxygen content in the gas of 95% or more. Usually only h is the terrain of ethylene interacts in a single pass over the catalyst and after separation of the desired product of ethylene oxide and removal of a suitable purge stream and carbon dioxide to prevent uncontrolled accumulation of inert substances and/or by-products, unreacted materials are returned to the reactor for oxidation. Only for illustrative purposes, the following terms are frequently used in commercial single reactor for ethylene oxide: SPG 1500-10000 The inlet pressure of 150-400 lbs/inch2 Supply input: ethylene 1-40% About23-12% CO22-40% Ethan 0-3% Argon, and/or methane and/or nitrogen: 0.3 to 20 hours/million chloropyrazole regulator from the total amount of diluent Coolant temperature 180-315°C The catalytic Converter temperature 180°C The conversion of O210-60% Performance OE (operating speed) 2-16 lb. MA/cu ft. catalyst/h The following non-limiting examples serve to illustrate the invention. Example Getting media The catalyst carrier was obtained using carrier - aluminum oxide as supplied by the manufacturer of the media and, first, subjected to processing by circulating a solution of 1300 g 1.25 M NaOH in water. When interacting NaOH solution c media temperature was raised from room temperature to 80°C for 30 minutes and then maintained this temperature for 1 hour. After processing, the solution was dried and 1300 g of circulating deionized water at room temperature modulating isovale for washing media for 1 hour, which is then dried. The wash procedure was repeated more than four times. Media, processed, dried at 150°C during the night. The catalyst And The catalyst was obtained by vacuum impregnation of the support by an ammonia solution of silver to obtain a target concentration of silver in the final product of 11.5%. Ammonia solution of silver, containing cesium promoter CsOH, was applied to obtain the target concentration in the final catalyst, ranging from 410 h/m to 650 hours/million Solution also contained rhenium from a solution of ammonium perrhenate with a target concentration of rhenium in the final catalyst 280 hours/million Impregnated carrier was progulivali on a conveyor belt moving through the furnace in an environment of pure nitrogen at a maximum temperature of 400°C. The catalyst In The catalyst was obtained in the same manner as catalyst A, except that the impregnated carrier was progulivali on a conveyor belt moving through the furnace in a nitrogen atmosphere, and 100 hours per million of oxygen. The catalyst With Catalyst C was obtained in the same manner as catalyst A, except that the impregnated carrier was progulivali on a conveyor belt moving through the furnace in an air environment. Test The catalysts were compared by testing for mass production speed 737, and selectivity of the catalysts, p is obtained on data carriers, shown in the drawing. The drawing shows the dependence of selectivity on time for the catalyst calcined in pure nitrogen (A), in nitrogen with small amounts of oxygen (C) and in air (C). The data clearly show improvements in the performance of the catalyst calcined in nitrogen with small amounts of oxygen. Since the present invention is specifically illustrated and described with references to preferred embodiments, professionals, qualified in this field, it will be obvious that various changes and modifications without deviating from the essence and scope of the invention. It is understood that the claims be interpreted as describing the disclosed embodiment, the alternatives discussed above and all equivalents. 1. A method of producing a catalyst useful in the production of ethylene oxide from ethylene and oxygen in the gas phase, which includes the impregnation of the inert substrate with a solution comprising a catalytically effective amount of compounds containing silver, a promoting amount of a compound containing alkali metal and a promoting amount of a compound containing a transition metal; calcining the impregnated substrate by heating the impregnated substrate at from about 200°to about 600°C for a period of time sufficient to reset the setting silver compounds containing silver to metallic silver and to decompose and remove almost all organic substances; the heating is carried out in an atmosphere comprising a combination of inert gas and from the approximate ppm to about 500 ppm gas comprising oxygen-containing oxidizing component. 2. The method according to claim 1, wherein the inert substrate comprises corundum. 3. The method according to claim 1, wherein the solution comprises an aqueous solution. 4. The method according to claim 1, wherein the compound containing silver includes silver oxalate, silver nitrate, silver oxide, silver carbonate, silver carboxylate, silver citrate, phthalate, silver, silver lactate, propionate, silver butyrate and silver salts of higher fatty acids and silver and combinations thereof. 5. The method according to claim 1, wherein the solution further includes a component selected from the group consisting of amines, alcohols, ammonia, lactic acid and combinations thereof. 6. The method according to claim 1, wherein the solution further includes Amin. 7. The method according to claim 1, wherein the solution further includes alkylenediamine having from 1 to 5 carbon atoms. 8. The method according to claim 1, wherein the solution includes a silver oxalate and Ethylenediamine. 9. The method according to claim 1, wherein the gas comprising oxygen-containing oxidizing component comprises CO2, NO, NO2N2O3N2O4and N2O5or prophetic the creation, able to form NO, NO2N2About3N2O4and N2O5or combinations thereof, under conditions of calcination, and optionally including SO3, SO2, R2O5, R2O3or combinations thereof. 10. The method according to claim 1, wherein the gas comprising oxygen-containing oxidizing component, includes O2. 11. The method according to claim 1, wherein the gas comprising oxygen-containing oxidizing component, includes O2in combination with NO or NO2. 12. The method according to claim 1, wherein the compound includes alkali metal includes lithium, sodium, potassium, rubidium, cesium or combinations thereof. 13. The method according to claim 1, wherein the compound includes alkali metal comprises cesium. 14. The method according to claim 1, wherein the transition metal comprises an element selected from groups 5b, 6b, 7b and 8 of the Periodic table of the elements and their combinations. 15. The method according to claim 1, wherein the transition metal comprises an element selected from the group 7b of the Periodic table of the elements and their combinations. 16. The method according to claim 1, wherein the transition metal comprises rhenium, molybdenum, tungsten or combinations thereof. 17. The method according to claim 1, wherein the transition metal comprises molybdenum. 18. The method according to claim 1, wherein the transition metal comprises rhenium. 19. The method according to claim 1, wherein the inert gas includes nitrogen, argon, krypton, helium, or a combination thereof. 20. The way p is 1, in which the inert gas includes nitrogen. 21. The method according to claim 1, wherein the heating is carried out in a period of from 1 min to about 1 o'clock 22. The method according to claim 1, wherein the inert substrate includes an oxide; a compound containing silver includes silver oxalate, silver oxide, silver carbonate, silver lactate and combinations thereof; the compound containing the alkali metal includes lithium, sodium, potassium, rubidium, cesium or combinations thereof; where the transition metal comprises rhenium; where the inert gas includes nitrogen, argon, krypton, helium, carbon dioxide or combinations thereof; where the atmosphere comprises from about 10 ppm to about 500 ppm gas comprising oxygen-containing oxidizing component. 23. The method according to claim 1, wherein the inert substrate comprises aluminum oxide, a compound containing silver includes silver oxalate, silver oxide, silver carbonate, silver lactate and combinations thereof; the compound containing alkali metal comprises cesium; where the transition metal comprises rhenium; where the inert gas includes nitrogen; where the atmosphere comprises from about 10 ppm to about 500 ppm gas comprising oxygen-containing oxidizing component. 24. The catalyst obtained by the method according to claim 1. 25. The method of oxidation of ethylene to ethylene oxide, which involves the oxidation of ethylene with molecular oxygen in the gas phase presence in the AI of the catalyst in a fixed bed, in a tubular reactor, where the specified catalyst was prepared by the method according to claim 1.
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