DE2339512A1 - CATALYTIC COMPOSITIONS OF SUBSTANCE AND PROCESS FOR THEIR MANUFACTURING - Google Patents

Description

Catalytic compositions of matter and processes for their

Manufacturing

The invention relates to catalytic compositions of matter and processes for their preparation and, in particular, compositions of matter of high catalytic activity which compared with are resistant to high temperatures while doing their good Keeping activity over long periods of use and for the oxidation of carbonaceous materials, for example Carbon monoxide, hydrocarbons and the like, to products that have a higher percentage of oxygen per molecule contain, such as oxidation intermediates, carbon dioxide and Water, the latter two materials from the standpoint

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are relatively harmless to air pollution, can be used. The new catalysts used to complete oxidation of exhaust gases that are non-burned or partially-burned carbonaceous Fuel components, such as carbon monoxide, hydrocarbons and oxidation intermediates, which are mainly carbon, Contain hydrogen and oxygen to effect. These catalysts can also be prepared so that they have a desirable low density and good heat resistance.

The catalysts according to the invention contain, as promoters for oxidations, the oxides of copper, chromium, a metal of Lanthanide group, especially cerium, together with one or more metals of the platinum group on a catalytically active refractory oxide such as alumina. The refractory oxide can be on a solid support with a small surface area to be present. The catalytically activating components preferably ground the catalytically active refractory oxide simultaneously or at least without calcining the support between the additions of these materials, individually or in the Form of mixtures, added.

It is known that in the combustion of carbonaceous Fuels for the purpose of generating energy, for example in piston engines, machines with rotating parts, etc., the combustion is generally incomplete and the products of the incomplete combustion are released to the atmosphere will. The exhaust gases contain a mixture of air pollutants, including carbon monoxide, which are saturated and unsaturated hydrocarbons and oxidized organic compounds such as aldehydes, organic acids and the like. Air pollution with these and other exhaust gases is particularly common in urban areas with heavy automobile traffic undesirable. Preventing the release of such oxidizable materials into the atmosphere is of great importance.

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because they contribute significantly to the problem of air pollution and the formation of nog and often have a detrimental effect on people Animals and plants that are exposed to high concentrations of these contaminants have an impact. ,

A measure to reduce the content of oxidizable gases in exhaust gases Materials consists in their oxidation by contact with molecular oxygen in the presence of catalysts. The catalysts are usually placed in the exhaust lines extending from the combustion zone and catalyze the conversion of partially-burned fuel with the free oxygen, either from a fuel-poor Operation of the combustion zone or comes from air or some other source of oxygen. The catalysts have usually has the disadvantage that its activity drops considerably when it is used at elevated temperatures for a long time will. This is partly because its structure is unstable in that it sinters at high temperatures, so that there is a shrinkage and thus a reduction in the exposed surface of the catalysts. It can also be caused by thermal degradation and a loss of strength in the catalyst body if it is used for a long time Temperatures in the exhaust pipes of internal combustion engines and turbines generally exceed 538 ° C or 649 ° C (1ooo ° F or 1200 F) is exposed to a grinding of the catalyst body especially when used in moving vehicles where it is subject to considerable vibration will. The resulting fine particles or other structural degradation products reduce the effectiveness of the catalyst. aside from that Many catalytic converters for the treatment of exhaust gases can in fact satisfactorily oxidize carbon monoxide effect, but have a relatively small effect on the conversion of hydrocarbons. Another one The problem that must be overcome is the creation of an oxidation catalyst that can reduce its effect

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the treatment of exhaust gases over a relatively long time, for example for at least up to about 80,000 kilometers (5o, ooo miles of vehicle operation) when used to treat car exhaust. If a current one Removal and regeneration of the catalyst is necessary to obtain the desired activity uiu can Difficulties in using and the cost of the system for combating air pollution from partially oxidized components oppose its introduction in exhaust gases and in any case cause undesirably high costs.

During the initial stages of the start of combustion, when the combustion zone, for example in an internal combustion engine, is cold or at a relatively low temperature, the exhaust gases contain a relatively large Amount of hydrocarbons, carbon monoxide and other partial combustion products. A catalyst for the oxidation of Exhaust gases are said to be effective both at such temperatures and at high temperatures. The catalyst according to the invention is an effective oxidation catalyst for both relatively low and high temperatures carbonaceous materials, especially partial combustion products of fuels In exhaust gases, the carbon monoxide, hydrocarbons and oxidized organic compounds such as aldehydes, organic acids, or intermediate products of combustion contain carbon dioxide, * water or other materials that, on average, contain a larger amount of bound oxygen contained per molecule. The reaction is carried out in the presence of free oxygen to maintain the oxidation. The new catalysts are resistant to high temperatures of, for example, up to about 900 ° C or above, as they can occur in the treatment of exhaust gases from internal combustion engines or other oxidation systems, the heat resistance depends on the carrier used. Thermal degradation, shrinkage and loss of strength

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Speed and catalytic activity are important when using the Catalysts according to the invention low. The treatment of exhaust gases with the catalysts according to the invention is effective, and frequent regeneration or replacement of the catalyst can be avoided, making the invention practical and measure that can be carried out relatively smoothly to reduce the release of oxidizable impurities to the atmosphere by converting the hydrocarbons, oxidation intermediates and carbon monoxide to, for example Carbon dioxide and water.

For catalytic converters used for the oxidation of automobile exhaust fumes it is important that they have a relatively low density and low weight loss and low shrinkage at high temperatures, i.e. have good thermal stability. The greater the density of the catalyst the longer it takes to heat it to operating temperature. For the elimination of the impurities In car exhaust, however, it is necessary to heat the catalytic converter quickly, as this is the initial stage of combustion is critical in terms of air pollution. In addition, the catalyst must not shrink too much when heated, so that the exhaust gases do not flow around the catalytic converter, i.e. part of the reaction zone is not filled by the catalytic converter so that some of the gas does not come into contact with the catalyst, or such contact is at least substantial is decreased. The catalysts according to the invention can be prepared so that they are relatively have low density and good thermal resistance.

The catalysts according to the invention contain, as a support, a solid, porous, refractory oxide, which is a metal of the platinum group and carries the oxides of copper, chromium and a metal of the lanthanide series. A particularly advantageous carrier is Aluminum oxide, which is an activated or catalytically active aluminum oxide, such as gamma or eta aluminum oxide or another

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whose form can be gamma-alumina, the alumina may contain small amounts of the other refractory oxides. Preferably, the carrier has before the impregnation with the promoters a surface area above about 50 to 100, preferably above about 200 m / g. The carrier can-before the impregnation deformed in the desired manner, or it may be, for example, "in the form of individual particles. That is, the carrier can be in the form of relatively small particles of various sizes and shapes, often in the form of particles having a largest dimension of about 0.4 to 25.4 mm (1/64 to one inch), which are referred to as macroparticles can exist. A variety of macroparticles that carry the catalytic components can be in the form of one more or less fixed bed is used in the oxidation zone will.

Another preferred support for the catalyst according to the invention can be in the form of a unitary skeletal structure with gas passages passing through it. Examples of such structures are the honeycomb beams, the a plurality of flow channels extending through the structure in the general gas flow direction exhibit. The flow channels do not have to extend in a straight line through the catalyst structure and can contain flow deflectors or spoilers. The through the catalyst structure leading channels can have any shape and size so that the catalyst has the desired surface area, and must be wide enough to allow relatively free passage of gases. The channels can be parallel or essentially parallel and extend from one side of the catalyst structure to the opposite Side, and these channels can be separated from each other by thin walls. The channels can be in extend in many directions and even communicate with one another. The channel inlet openings can be via im substantially the entire area or the entire cross section of the catalyst structure be distributed. This honeycomb structure

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can be made of a catalytically relatively inert material, such as a fixed ceramic material, or they can have a metallic character. The inert structure usually has a small surface area of for example

2 se less than about 10 or even less than about 1 η / g. (The specified surfaces are determined by BET or a similar method.) The inert structure as a support for the more porous refractory oxide supports such as the above-mentioned alumina with larger size Surface can be used (see US Pat. No. 3,565,830). In these cases, the coating on the carrier can be larger Surface often make up about 5 to 25, preferably about 1o to 2o wt. Of the carrier of low surface area.

The porous, catalytically active support material of relatively large surface area of the catalyst according to the invention carries catalytically effective amounts of one oxide each of copper, chromium and at least one rare earth metal Lanthanide group. Each of these oxides usually constitutes a small proportion of the catalyst. The catalyst can too contain a small, catalytically effective amount of a platinum group metal. Other components can also be included in the Catalytic converter be present and have a catalytic effect. These other components include nickel, vanadium, iron and the like and their oxides or other compounds thereof. Barium oxide, zirconium oxide, strontium oxide and the like can also be used Improvement of the heat resistance of the catalyst can be introduced into the carrier.

Oxides of the rare earth metals preferred for the catalyst according to the invention are those of cerium, Praseodymium, samarium, gadolinium and mixtures thereof. Cerium oxide is used with particular advantage. This component can be added to the support in a first impregnation step to form a diffusion partition, or it can

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are added to the carrier at the same time as the other promoters. The amount of oxide of the rare earth metal in the catalyst is often about 3 to 20, preferably about 5 to 10 wt .-% of the total catalyst. This component improves the heat resistance of the catalyst as measured by the volume shrinkage and acts to increase the density of the catalyst, which is caused by an increased copper oxide content.

The rare earth metal can be deposited on the substrate in various forms and by various methods will. For example, the oxide can be suspended in water together with the carrier and thereby deposited on the carrier will. Alternatively, the rare earth metal can be in the form of a salt such as nitrate, an organic salt, etc., are deposited on the carrier and converted into the oxide by calcination. That for example in the form of a salt in solution metal of the rare earths can be deposited on a carrier in the Applied in the form of fine particles and the carrier provided with the coating can then be brought into the desired shape and calcined. The impregnation of the carrier with the aqueous solution of the salt can be carried out by various methods take place. For example, the carrier can be added to a solution of the metal salt or a solution of the salt can be sprayed onto the carrier, or the carrier can first be added to saline and then further Impregnation can be sprayed with the solution or vice versa. The carrier can be calcined after it has been treated with a Solution of the rare earth metal is impregnated.

Chromium oxide and copper oxide are preferably in the catalyst according to the invention in an amount in the range of about 3 to 2o, preferably about 4 to 10% by weight of chromium oxide or about 1 to 1o, preferably about 1 to 3 or 5% by weight

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Copper oxide, based on the total catalyst, present. It is desirable that the total amount of the oxide of the metal of the sel ten earths and chromium oxide is no greater than about 3o wt .-% of the total catalyst and preferably 5 to 20%. Copper oxide increases the density of the catalyst and can decrease its heat resistance, especially when used in quantities considerably more than 3% is present. Therefore, copper oxide is advantageously used in a limited amount.

Those consisting of metal oxides and a platinum group metal Promoters can be added to the carrier in any order desired, with two or more of these components or even all of them can be added at the same time. According to one method, the copper and chromium components are added together and are preferably added together with the rare earth metal. The chrome can do that Carriers in the form of chromic acid are added. However, the chromium component can also be in the form of a salt used in the Calcination gives the oxide, for example in the form of the nitrate or an organic amine salt, chromium acetate and the like., be used. Chromic acid is preferred because it gives off water when calcined, while the nitrates are nitrogen oxides, that pollute the atmosphere. The copper oxide can be added to the carrier in any suitable manner and can be deposited on the support by treating it with a slurry of copper oxide in a volatile organic liquid such as methanol, ethanol, acetone and the like, after which the slurry is evaporated so that a deposit of metal oxide remains. Alternatively the copper component can be added to the carrier in the form of an aqueous solution of a salt, in particular an inorganic one Salt, which yields metal oxide on calcination, can be added.

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The platinum group metal is preferably present in the catalyst in a metallic state. To the metals of the platinum group include platinum, palladium, rhodium, and the like, as well as mixtures of such metals such as platinum and palladium. That Platinum group metal is usually in the catalyst in an amount in the range of about 0.01 to 5 wt% or more, preferably about 0.02 to 2% by weight of the total catalyst present. If both platinum and palladium are present in the catalyst, platinum often forms the majority this component. For example, the catalyst can be about 60 to 95% by weight platinum and 5 to 40% by weight palladium on the total amount of these metals / included. Due to the presence of larger amounts of platinum group metals the cost of the catalyst is considerably increased.

The deposition of the metal of the platinum group on the alumina support of the catalyst according to the invention can take place simultaneously with the metal oxide components, or the platinum group metal can then be added, and preferably the platinum group metal is the last component or promoter added to the support. The metal the platinum group can be added to the carrier by various methods. For example, solutions of soluble compounds can be used of the platinum group metal such as hydrochloric acid, a resinate of such metal, or another Organometallver bond, which is "under the thermal influence decompose after calcination or form a decomposable precipitate. When aqueous solutions of compounds of the platinum group metal is used, the metal can be treated by various methods, for example by treating the solution with hydrogen sulfide, can be precipitated from the solution in contact with the carrier.

When calcining the catalyst, various compounds of two or more metals in the catalyst, both

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for example copper chromate, formed v / earth. By being present such compounds is the .katalytische activity of the catalyst generally not deteriorated. The catalyst can

after adding each of the components or mixtures of these components or after all of these components are incorporated therein, calcined. Preferably takes place between the additions of activating metal components, essentially no calcination of the support, and it is particularly preferred to use all of these components to be added simultaneously in the form of a common solution in contact with the carrier. Suitable calcination temperatures are in the range from about 300 or 500 to 12oo C or above, but should not be so high that the catalytic activity of the mass is impaired.

The catalysts according to the invention can be used for the oxidation of various chemical feedstocks by contact be used with molecular oxygen. Some oxidations can take place at relatively low temperatures; most of time However, such oxidations are carried out at elevated temperatures of, for example, at least about 150.degree. C., preferably about 200 to 900 ° C and generally while the feed is in the vapor phase. The feed materials are those that are amenable to oxidation and contain carbon and can therefore be described as containing carbon regardless of whether they are organic or inorganic compounds. The catalysts are suitable thus for a use for the oxidation of hydrocarbons, oxygen-containing organic components, carbon monoxide Such materials may be present in exhaust gases from the combustion of carbonaceous fuels, and the catalysts according to the invention can therefore be used for the oxidation of such exhaust gases. The exhaust gas from containing hydrocarbons Internal combustion engines operated as fuel and other exhaust gases can come into contact with the catalytic converter and molecular oxygen are oxidized. The molecular

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Oxygen can be present in the effluent as part of it, or it can be in the form of air or other desired Form with greater or lesser oxygen concentration can be added. Possess the products of oxidation a greater ratio of oxygen to carbon than the oxidized charge. Lots of them Reaction systems are known.

The following examples illustrate the invention. Details in parts and percent relate to weight, unless otherwise stated.

Example I.

This example illustrates the simultaneous addition of all catalytically activating metals to activated alumina spheres. A solution is prepared by adding 1 242 g Cu (NO ₃ ) ₂ 3H ₂ O, 2 417 g Ce (NO ₃ ) ₃ 6H ₂ O, 1 26o g CrO ₃ (chromic acid, H ₃ CrO ₄ ) and 16, 1 g of Pd (NO ₃ ) - to be dissolved in 13.6 l of deionized water at room temperature. This solution is poured onto 11.3 kg (25 lbs.) Activated alumina balls and the materials mixed together. The mixture is partially dried using steam heating in the jacket of a fixed bed dryer, then transferred to a drying oven at 120 ° C and dried overnight. Then, the mixture is introduced in a large gas-fired Of en _e of 1oo ° C. ^{The temperature is increased to 1000 °} C. within 4 to 5 hours and held at 1000 ^° C. for 2 hours. Then it is cooled. After the temperature of the catalyst has dropped to 7oo to 800 ⁰ C, the oven door is opened, and the catalyst is allowed to cool as rapidly as possible. The catalyst is then sieved to separate less than 8 mesh particles and bubbled with air to remove dust generated during drying and calcining. The finished catalyst prepared as described above contains nominally 3% by weight CuO, 7% by weight CeO ₃ , 7% by weight Cr ₃ O ₃ and 0.04% by weight Pd.

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Example II

In this example, ceria is added to activated alumina and the remaining promoters are then introduced. A catalyst is prepared according to the procedures of Example 1 except that 11.3 kg (25 pounds) of alumina spheres are first deionized _{with a solution made by dissolving 2,488 Ce (NO 3} ) ₃ '6H _{3 O in 11 1} Water is maintained at room temperature, can be impregnated. The spheres are dried at 120 ° C. overnight. The mass obtained contains 8% by weight of CeO ₃ . The spheres are then, as in Example 1, impregnated with a solution containing copper nitrate, ceronitrate, chromic acid and palladium nitrate, and then dried and calcined. The finished catalyst contains 3% by weight CuO, 10% by weight CeO, 7% by weight Cr ₀ O., and 0.04% by weight Pd.

Example III

In this example, a solution containing all of the metal salts is slurried with an aluminum oxide powder, and the material is then extruded and formed into spheres. A solution was prepared by adding 181 g Cu (CE ₃ COO) ₂ -H ₃ O, 333 g CrO ₃ , 730 g Ce (NO ^) _ · 6Η-0 and 4.40 g Pd (NOO ₀ in 56o ml deionized Water by heating to 35 _{° C. The solution was poured onto 4,000 g of Al 3} O ₃ powder and kneaded for 10 minutes. 800 ml of NII.OH were added to Dent Geraisch, and the mixture was kneaded for a further 10 minutes material was extruded through a 2.54 mm die (o, 1oo "die) and then shaped into spheres. the spheres were calcined for 4 hours at 1oo ° C and dried for 2 hours at 1000 ⁰ C. the finished catalyst contained o, o4% by weight Pd, 2% by weight CuO, 7% by weight Cr ₃ O ₃ and 8,% by weight CeO ₃ .

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Example IV

A solution containing all of the metal salts is slurried with an alumina powder and then extruded and formed into spheres. After calcination ^ the material is impregnated with palladium. A solution was prepared by dissolving 50 g Cu (CH ₃ COO) ₂ -H ₂ O, 91 g CrO _3, and 198 g Ce (NO ₃ ) ₃ -6K ₃ O in 16 40 ml of room temperature deionized water . This solution was _{added to 2292 g of Al 2} O ₃ powder, and the mixture was kneaded for 10 minutes. 175 ml of NH ₄ OII were added together with 100 ml of HO, and the mass was kneaded for a further 10 minutes. This material was passed through a 2;.. Extruded 54 mm nozzle (0.I00 "die) and formed into balls The balls were dried in an oven at 80 ⁰ C and calcined for 2 hours at 1000 ⁰ C These beads were coated with a Pd (NO ₃ ) ₂ solution impregnated, dried and calcined for 2 hours at 500 ° C. The catalyst obtained in this way contained 0.02% by weight of Pd, 1.2% by weight of CuO, and 4.1% by weight of Cr ₂ O ₃ , 4.7 wt% CeO ₃ and 90% Al ₃ O ₃ .

Example V

A solution containing all of the metal salts is used to form a coating on a preformed activated alumina extrudate. A solution was prepared by adding 268 g Cu (NO ₃ ) ₂ · 3H ₂ O, 406 g CrO ₃ , 891 g Ce (NO ₃ ) ₃ '6H ₃ O and 8.35 g Pd (NO ₃ ) - in 2 2oo ml of deionized water at room temperature. This solution was applied to the surface of 5 5oo. g activated ΑΙ-Ο -, - extrudate sprayed on. The material was dried for 17 hours at 12o ^o C before it was calcined for 2 hours at 1000 ⁰ C. The finished catalyst contains 1.4% by weight CuO, 4.9% by weight Cr ₃ O ₃ , 5.7% by weight CeO ₃ and 0.04% by weight Pd.

Example VI

Activated aluminum oxide spheres are simultaneously impregnated with chromium and cerium ions, calcined and then simultaneously

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impregnated with cupric ions and palladium ions. A solution was prepared by dissolving 2 162 g of Cr (KO ₃ ) ₃ «9H ₂ O and 1 180 g of Ce (NO ₃ J ₃ * 6H ₃ O in 700 ml of Ii ₃ O by heating to 75 ° C. This solution of '75 ⁰ C O was added at room temperature to the surface 5 000 g of activated Al ₂ sprayed ₃ balls. the provided with the coating spheres were dried in a coating device with hot air was until the moisture content is less than 12%. Then, the balls were calcined for 2 hours at 1000 C. The material thus obtained contained 7% by weight of Cr ₃ O ₃ and 8% by weight of CeO ₂ . % Pd and 1.0% by weight CuO deposited from a nitrate solution The spheres obtained were dried at 11 ° C. and calcined at 500 ° C. for 2 hours.

Example VII

A copper oxide / ceria / chromia / alumina powder was deposited as a coating on a honeycomb structure, and Pt and Pd were added. A solution was prepared by dissolving 221 g Cu (NO ₃ ) ₂ * 3H ₂ O, 335 g CrO ₃ and 734 g Ce (NO ₃ ) ₃ * 6H ₂ O in 920 ml H ₃ O at a temperature of 55 ° C so that a total of 1,440 ml of solution was obtained. A slurry was prepared from the above solution and 1,200 g of Al ₂ O _{3 powder.} The mass was 17 hours in an oven at 12o ° C dried, milled, so that s ^ e calcined by a sieve having a mesh aperture of o, 43 mm passed (to pass 4o mesh) and 2 hours at 1 000 ⁰ C. 175 g of the calcined powder were ground with 175 ml of H ₂ O and 3.5 ml of concentrated HNO ₃ in an 0.95 liter container (in quart mill jar) at 99 rpm for 17 hours, so that a coating compound (slip) was formed became. Cordierite honeycomb with about 25o gas passage

Each 6.5 cm (square inch) cross-section was put into the coating dipped, dried for 2 hours at 120 ° C. and calcined for 2 hours at 50 ° C., with an average of about 11.6% coating mass being deposited on the honeycomb. The one with the cover provided honeycombs were immersed in tetramine Pt (II) hydroxide for 1 minute + Tetramine-Pd (II) hydroxide immersed in an oven

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dried at 120 ° C. and calcined at 50 ° C. for 2 hours. The catalyst obtained in this way contained 0.16% by weight of Pt and 0.05 Wt% Pd.

Example VIII

To illustrate the improved properties of the catalysts according to the invention for the oxidation of exhaust gas a catalyst prepared according to Example V was tested. A gas came into contact with a bed of the catalyst with a throughput rate of 40,000 volumes per hour. The gas contained 3.0% oxygen, 1.0% carbon monoxide, 300 ppm ethylene, 10.0% carbon dioxide, 500 ppm nitrogen oxide, remainder Nitrogen. Before entering the catalyst, the gas was heated to bring the catalyst temperature to a certain value and the gaseous effluent obtained at each of these temperatures was reduced to its carbon monoxide and content Ethylene analyzed. These values were plotted against the oxidation temperature, measured about 0.64 cm in front of the catalyst inlet. From a plot of the oxidation temperature against the amounts of carbon monoxide and ethylene in the drain, the Temperatures for a 5o% conversion of carbon monoxide to carbon dioxide and a 5o% conversion of ethylene to carbon dioxide and water determined. These values were 255 ° C for the 50% conversion of carbon monoxide and 325 ° C for the 50% Conversion of ethylene.

A number of catalysts with varying contents of _{CuO, Cr 2} O _{3 , CeO 2} and Al ₂ O ₃ were prepared and evaluated for density and heat resistance. The catalysts did not contain any platinum group metal; however, it is believed that the addition of a small amount of such a component does not affect the values obtained. The results are compiled in the following tables.

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TABLE 1 Influence of the composition on the density of the catalyst

CuO

Composition% by weight

QeOn

7 7 5 7

1o 5 7 4

8th 84 3 88 5 88 8th 83 5 83 8th 83 7th 81 5 83

Density of the catalyst 'ml

o, 58 o, 7o o, 57 o, 57 o, 58 o, 61 o, 72 o, 8o

The values in Table 1 show the influence of CuO on the increase in density, CeO ₂ on the decrease in density and the possible interchangeability of Cr ₃ O- and with regard to a decrease in density to a certain extent. ",

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TABEL Influence of the composition on the shrinkage of the catalyst composition

Wt%

CuO Cr 0 CeO Al ₂ O 2 11 4th 83 2 9 6th 83 3 7th 7th 83 4th 5 8th 83 4th 7th 6th 83

Loss of catalyst volume after 24 hours. Heat of the catalyst to 9 82 ° C

(18oo ° F)

Volume loss ,%

. 4, ο

4.4

4.8

18, ο

19, ο

These values show the disadvantageous influence of larger amounts of CuO on the heat resistance of the catalyst. Although this one Difficulty and the increase in the density of the catalyst due to the presence of larger amounts of copper in some Extent by increasing the amount of rare earth oxide and chromium oxide can be counteracted, the catalysts can thereby but due to the total amount of basic metal oxides present are too dense.

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Claims (1)

3 AUG. IJ? 3 Claims 1, "Composition of substances for the oxidation of carbonaceous Materials consisting essentially of catalyst promoter effective amounts of both copper oxide and chromium oxide, an oxide of a rare earth metal and a platinum group metal on a solid, catalytically active heat-resistant carrier. 2. The composition of matter according to claim 1, characterized in that that the refractory support is alumina. 3. The composition of matter according to claim 2, characterized in that that they have about 5 to 1o% cerium oxide, about 1 to 5% copper oxide, about 4 to 10% chromium oxide and about 0.02 to 2% Contains platinum group metal. 4. A composition of matter according to claim 3, characterized in that it contains both platinum and palladium. 5. The composition of matter according to claim 4, characterized in that that it contains 1 to 3% copper oxide. 6. A composition of matter according to claim 4, characterized in that that the copper, chromium, cerium and platinum group metal components are added to the carrier without the carrier is calcined in between. 7. The composition of matter according to claim 6, characterized in that that the addition of the copper, chromium, cerium and platinum group metal components takes place at the same time. 8. Process for oxidizing a carbonaceous material, characterized in that the material is in gaseous form by contact with oxygen and the catalyst together, Setting of claim 1 oxidized. - 19 409808/1080 7339512 B-11O8 9. The method according to claim 8, characterized in that the
carbonaceous material is an exhaust gas from combustion
of a hydrocarbon fuel. 10. The method according to claim 9, characterized in that the
heat-resistant catalyst support is aluminum oxide. 11. The method according to claim 1o, characterized in that the Catalyst about 5 to 10% cerium oxide, about 1 to 5% copper oxide, about 4 to 10% chromium oxide and about 0.02 to 2% platinum group metal contains. 12. The method according to claim 11, characterized in that the catalyst contains platinum and / or palladium. 13.Verfahren according to claim 12, characterized in that the carbonaceous material is an exhaust gas from the combustion of a hydrocarbon fuel. 14. The method according to claim 12, characterized in that the Catalyst by adding the copper, chromium, cerium and platinum group metal components to the carrier without intermediate calcining of the carrier. 15. The method according to claim 14, ^ characterized in that the carbonaceous material is an exhaust gas from the combustion
a, hydrocarbon fuel. 16. The method according to claim 15, characterized in that
the catalyst by the simultaneous addition of copper,
Chromium, cerium and platinum group basic metal components to the
Carrier has been manufactured. - 2o - 409808/1080 I ¹ 17. The method according to claim 15, characterized in that the copper oxide content of the catalyst is about 1 to 3%. - 21 - 409808/1080