The method of applying a catalyst on a ceramic carrier
(57) Abstract:The invention relates to catalytic chemistry and can be used when applying particles and films of catalytically active metals on the surface of the ceramic monoblock media. The proposed method comprises applying to the surface of the carrier composition containing dispersed platinum group metal in the organic component, followed by heating and firing. As the applied composition using ultrafine metal deposited on the naphthalene used as the organic component, the ultrafine metal has additionally also use silver, gold or alloys of the above metals. The technical result is a simplification of the method and increase the service life of the catalyst. 1 C.p. f-crystals, 2 tab. The invention relates to catalytic chemistry, in particular for the application of the particles and films of catalytically active metals on the surface of the ceramic monoblock media.Known method of applying a palladium on appropriate media (U.S. patent N 4833114, B 01 J 23/44, date of publ.27.07.88) by application to the surface of the solution dinitrophenolate with Pawlicki carrier with a solution of compounds of platinum group metals (U.S. patent N 5141912, B 01 J 23/26, date of publ. 29.06.89) with subsequent activation.There is also known a method of producing the catalyst by deposition on a substrate of a noble metal such as platinum or palladium (application N 3926551, Germany, B 01 J 23/44, publ. 14.02.91).However, these two methods in the case of impregnation compounds of metals suggest the presence of a porous medium and is not applicable for bulk carriers, and in the case of deposition (vacuum or plasma) suggest the presence of complex equipment.Closest to the proposed invention is a method of applying a catalyst of platinum group metal (application Japan # 63 - 6267, B 01 J 23/40, date of publ.09.02.88) by applying to the medium a mixed solution in an organic solvent containing a platinum group metal in the form of fine powder and ions, with the addition of inorganic binder, followed by heating and firing.The disadvantages of this method include the presence of inorganic binder to promote adhesion of particles or metal film to the substrate, which reduces the active surface of the metal. The presence of ionic compounds metal, decomposing at a temperature firing, Privodino undesirable impurities. The disadvantage of this method is the high firing temperature required for the decomposition of ionic compounds and promote adhesion of the metal to the substrate (700 - 800oC).The task of the invention is to increase the service life of the catalyst by increasing the adhesion of the metal to the substrate and the exclusion of impurities contaminating the catalyst, and the simplification of manufacturing technology by reducing the temperature of the deposition process of the catalyst.The problem is solved by a method of applying a catalyst on the ceramic carrier, comprising coating the surface of the carrier composition containing dispersed platinum group metal in the organic component, followed by heating and firing, when this composition is applied to the preheated carrier, as applied composition using ultrafine metal deposited on the naphthalene used as the organic component, and as the ultrafine metal has additionally also use silver, gold or alloys of those metals.Before application of the composition of the ceramic carrier is heated to 90 - 100oC, heated Nan is>The task can be solved also by a method of applying a catalyst on the ceramic carrier, comprising coating the surface of the carrier composition containing dispersed platinum group metal in the organic component, followed by heating and firing the coating composition used ultrafine metal, dispersed in an organic component comprising terpineol with the addition of dimethylformamide in a ratio of 250 : 1 by weight.h., and as the ultrafine metal has additionally also use silver, gold or alloys of the above metals, each of which is injected into the organic component in the ratio of 1 : 50 by weight.h. The heat applied to the carrier of the composition is carried out at 100 - 120oC and subsequent annealing at 350 - 400oC.Ultrafine particles of metals (smaller than 1 μm) have a high surface activity (including catalytic). However, they are difficult to maintain in the form of particles separated because they have a tendency to rapid building-block approach that entails the loss of valuable properties of their surface. Consequently, it is proposed to use particles of these metals deposited on the crystals of naphthalene as organic the walkie-talkie.Due to ultradispersed particles of coating metal and mikroheranhvatho the surface of the carrier conduct low-temperature deposition process of the catalyst with high adhesion of the metal particles to the surface of the substrate; an exception inorganic component, enveloping metal particles, allows you to release a greater proportion of surface-active atoms and to increase the contact surface of the catalyst.Use as a coating composition, organosol metal-naphthalene allows you to eliminate pollutants catalyst, since the low-temperature metallization process passes the complete removal of naphthalene (without formation of impurity residues). Terpineol as a component of the organic component in the second composition also does not introduce impurities, fully uletuchivayas during drying and annealing. Dimethylformamide, proposed by the present invention the ratio with terpineol, has peptizyme effect. At its introduction in the ratio of less than 1 wt. including the effect peptization is missing, with an increase of more than 1 wt.h. an additional effect is not observed. The ratio of metal - organic component is made on the basis that the reduced metal is less than 1 wt.h. ukhudshe wt.h. increases the viscosity of the composition and complicated process of applying a catalyst.The heat applied to the carrier structure in the first embodiment of the method carried out in a range of 90 - 100oC, at a temperature of less than 90oC organosol does not melt, and at a temperature of more than 100oC catalytic coating becomes more porous and uneven, with the inclusion of products of thermolysis. In the second variant of the method, the reducing temperature is less than 100oC increases the drying time (reducing the adaptability of the process), and an increase of more than 120oC reduces the quality of the catalytic coating (non-uniform, bubble) due to intensive evaporation of the organic component. The firing temperature of 350 - 400oC sufficient for optimal results, decreasing deteriorates the workability of the process (increase of time without improving quality).In General, the method is as follows.It heated up to 90 - 100oC monolithic ceramic block that you want to put a layer of catalytically active metal, touch otterbine in the form of a rod, is convenient for this configuration, size, solid organosol composition naphthalene - Ag, Au, Pt or Pd is after applying the molten organosol media is maintained at the same temperature for 10 15 min to complete sublimation of naphthalene, after which the medium is heated to 300-400oC and held for 5 to 10 minutes before formation of the metal film.Example 1. Heated to 90oC ceramic media put solid organosol composition naphthalene - Ag. Organosol is melted and evenly applied to the surface of the carrier. After that, the medium was incubated for 10 min to complete sublimation of naphthalene, after which the medium is heated to 350oC and can withstand before formation of the metal film.Examples of implementation of the proposed method with different ultrafine metals and their alloy are summarized in table 1.For the implementation of the second variant of the method for obtaining the composition of ultrafine metal - organic component in the liquid state in the form of Hydrosol, solid organosol naphthalene - Ag, Au, Pt, Pd or their alloys is shaken out three times naphthalene twenty-fold by weight, the amount of ethanol or acetone, after decanting, the last portion of solvent to loose draught add terpineol and dimethylformamide in the ratio of 250 : 1 by weight.h., the ratio of metal - organic component of the stand 1 : 50 wt.h. The obtained liquid composition 10 - 20 min treated IU anatoy temperature, then heated to 100 to 120oC to remove solvent, followed by baking at 350 - 400oC for 5 - 10 min before formation of the metal film.Examples of specific performance with different ultrafine metals and options temperature regime are summarized in table 2.The use of the invention allows to reduce the temperature of the process of preparation of the catalyst in 2 times, which gives the possibility to reduce energy costs and simplifying used heating equipment. Increasing the surface contact of the catalyst in comparison with the prototype allows to reduce the amount of damage an expensive metal to achieve the desired conversion of gas.High adhesion of the metal to the surface reduces the mechanical entrainment of the particles and increases the service life of the catalyst.The proposed methods of application of the catalyst (liquid and solid) are a versatile tool and allow you to cover any configuration of media, including hard-to-reach places, the internal channels allow the use of drip method of application, and the application of the composition of the brush by dipping, etc. will find The S="ptx2">1. The method of applying a catalyst on the ceramic carrier, comprising coating the surface of the carrier composition containing dispersed platinum group metal in the organic component, followed by heating and annealing, characterized in that the composition is applied to the preheated carrier, as applied composition using ultrafine metal deposited on the naphthalene used as the organic component, the ultrafine metal has additionally also use silver, gold or alloys of the above metals.2. The method according to p. 1, characterized in that before applying the composition of the ceramic carrier is heated to 90 - 100oC, the heat applied to the carrier of the composition is carried out at the same temperature, and the subsequent firing - at 350 - 400oC.
FIELD: alternate fuel manufacture catalysts.
SUBSTANCE: invention relates to generation of synthesis gas employed in large-scale chemical processes such as synthesis of ammonia, methanol, higher alcohols and aldehydes, in Fischer-Tropsch process, and the like, as reducing gas in ferrous and nonferrous metallurgy, metalworking, and on gas emission detoxification plants. Synthesis gas is obtained via catalytic conversion of mixture containing hydrocarbon or hydrocarbon mixture and oxygen-containing component. Catalyst is a complex composite containing mixed oxide, simple oxide, transition and/or precious element. Catalyst comprises metal-based carrier representing either layered ceramics-metal material containing nonporous or low-porosity oxide coating, ratio of thickness of metallic base to that of above-mentioned oxide coating ranging from 10:1 to 1:5, or ceramics-metal material containing nonporous or low-porosity oxide coating and high-porosity oxide layer, ratio of thickness of metallic base to that of nonporous or low-porosity oxide coating ranging from 10:1 to 1:5 and ratio of metallic base thickness to that of high-porosity oxide layer from 1:10 to 1:5. Catalyst is prepared by applying active components onto carrier followed by drying and calcination.
EFFECT: increased heat resistance and efficiency of catalyst at short contact thereof with reaction mixture.
13 cl, 2 tbl, 17 ex
FIELD: methods of production a synthesis gas.
SUBSTANCE: the invention is pertaining to the process of production of hydrogen and carbon oxide, which mixture is used to be called a synthesis gas, by a selective catalytic oxidation of the hydrocarbonaceous (organic) raw material in presence of the oxygen-containing gases. The method of production of the synthesis gas includes a contacting with a catalyst at a gas hourly volumetric speed equal to 10000-10000000 h-1, a mixture containing organic raw material and oxygen or an oxygen-containing gas in amounts ensuring the ratio of oxygen and carbon of no less than 0.3. At that the process is conducted at a linear speed of the gas mixture of no less than 2.2 · 10-11 · (T1 + 273)4 / (500-T2) nanometer / s, where: T1 - a maximum temperature of the catalyst, T2 - a temperature of the gas mixture fed to the contacting. The linear speed of the gas mixture is, preferably, in the interval of 0.2-7 m\s. The temperature of the gas mixture fed to the contacting is within the interval of 100-450°C. The maximum temperature of the catalyst is within the interval of 650-1500°C. The technical effect is a safe realization of the process.
EFFECT: the invention ensures a safe realization of the process.
10 cl, 5 ex
FIELD: heterogeneous catalysts.
SUBSTANCE: catalytic system comprises (i) high-silica fibrous carrier characterized by 29Si MNR spectrum, in which lines with chemical shifts -100±3 ppm (line Q3) and -110±3 ppm (line Q4) are present at ratio of integral intensities Q3/Q4 from 0.7 to 1.2; IR spectrum, in which absorption bands of hydroxyl groups with wave number ν=3620-3650 cm-1 and half-width 65-75 cm-1 are present; which carrier has specific surface SAr=0.5-30 m2/g as measured by BET method from thermal desorption of argon, surface area SNa=10-250 m2/g as measured by alkali titration method, at SNa/SAr ratio 5 to 30; and (ii) at least one active element. The system represents geometrically structured one constituted by microfibers with diameter 5-20 μm and additionally has active centers characterized in IR spectra of adsorbed ammonia by presence of an absorption band with wave numbers ν=1410-1440 cm-1.
EFFECT: increased catalytic activity, resistance to deactivation, and selectivity.
3 cl, 7 ex
FIELD: production of hydrogen and carbon oxide referred to as synthesis gas by selective catalytic oxidation of hydrocarbon raw material in presence of oxygen-containing gases.
SUBSTANCE: proposed method includes bringing the starting material in contact with catalyst at hourly volume rate of gas within 10,000-10000000 h-1; mixture contains organic material and oxygen or oxygen-containing gas in the amount ensuring ratio of oxygen to carbon no less than 0.3; electric current is passed through at least part of catalyst. Used as catalysts are complex composites including metallic carriers.
EFFECT: possibility of quick and safe ignition of catalyst; increased degree of conversion and selectivity under conditions of change of load in wide range.
24 cl, 7 ex
FIELD: methods of storage of hydrogen in catalytic systems functioning on basis of cyclic hydrogenation/de-hydrogenation reactions of condensed and poly-nuclear aromatic compounds; hydrogen generators; hydrogen engines or plants.
SUBSTANCE: proposed catalytic composite material contains organic substrate as hydrogen source which is liable to hydrogenation/dehydrogenation reactions. Material contains heterogeneous catalyst including carbon or oxide carrier at high specific surface and metal of VIII (platinum) group applied on this surface at mass ratio of substrate and catalyst from 10:1 to 1000:1. Organic substrate contains the following aromatic hydrocarbons: condensed, poly-cyclic, poly-unsaturated, aromatic oligomers and polymers: biphenyl or its functional derivative, or terphenyl, or naphthalene, or anthracene, or functional derivative of one or other, polystyrene or its copolymer, polyacetylene or polycumulene. Proposed method consists in charging the composite material with hydrogen at high pressure and separation of hydrogen from it at low-pressure heating. Charging is carried out at contact of organic substrate and heterogeneous catalyst at temperature of from 50 to 180°C and hydrogen pressure of from 1 to 100 atm; separation of hydrogen is carried out at contact of hydrogenated of organic substrate with the same catalyst at temperature of from 200 to 350°C at atmospheric pressure.
EFFECT: enhanced efficiency.
9 cl, 2 dwg, 2 tbl, 7 ex
FIELD: organic synthesis catalysts.
SUBSTANCE: invention relates to novel catalysts that can be used, in particular, for selective hydrogenation of polyunsaturated hydrocarbons, deep oxidation of carbon monoxide, organic and organohalogene compounds, sulfur dioxide oxidation, selective chlorination and oxychlorination of hydrocarbons, nitrogen oxide reduction, and reuse of gaseous and liquid wastes. Catalytic system represents geometrically structured one including microfibers of high-silica fibrous carrier 5-20 μm in diameter, which is characterized by existence in IR spectrum of hydroxyl group spectral band having wave number ν=3620-3650 cm-1 and half-width 65-75 cm-1, by having specific surface SAr=0.5-30 m2/g as measured via BET method involving thermal desorption of argon, and at least one active element. In addition, carrier has specific surface value measured by alkali titration method SNa=5-150 m2/g at SNa/SAr ratio (5-50):1. Active element is of the nature capable of forming charged metallic or bimetallic clusters with specific bands in the region of 34000-42000 cm-1 and ratio of integral intensity of band 34000-42000 cm-1 (corresponding to charged metallic or bimetallic clusters) to integral intensity of band with maximum at 48000 cm-1, corresponding, respectively, either to metallic or to bimetallic particles, at least 1.0.
EFFECT: increased catalytic activity, increased resistance of catalyst to deactivation and elevated selectivity thereof in heterogeneous reactions.
4 cl, 6 ex