The method of obtaining a silver catalyst, the method of producing ethylene oxide and an activation method of a silver catalyst

 

(57) Abstract:

A method of obtaining a silver catalyst on the carrier for vapor-phase oxidation of ethylene to ethylene oxide comprises impregnating a porous carrier having a specific surface area of 0.2-2.0 m2/g hydrocarbon solution of a silver salt of an organic acid in an amount of 3 to 25 wt.% silver on the carrier at 150-200oC for less than 1 h, the activation of the impregnated carrier at 200-300oWith, impregnated activated carrier at 300-400oC for less than 1 h, in the fourth stage at 400-500oC for less than 1 h in an inert atmosphere containing one or more inert gases. The impregnated impregnated with silver media perform anhydrous alcoholic solution containing a compound of an alkali metal. The catalysts prepared above methods have improved characteristics, in particular, stability in the application of them to obtain ethylene oxide vapor-phase oxidation of ethylene with molecular oxygen. 3 S. and 31 C.p. f-crystals, 10 PL.

The present invention relates in General to the silver catalyst on a carrier suitable for vapor-phase oxidation of ethylene to ethylene oxide. More specifically, the present invention is about what I silver) caesium.

Modern art

In this sphere, it has long been known application of the silver catalysts on carriers for oxidation of ethylene to ethylene oxide. Additionally, during these years was added promoting various metals to further enhance the performance of the catalysts. In particular, describes the use of alkali metals in varying amounts and add them in different ways. A very extensive review of the patent literature is given in the patent GB (great Britain) N 2671764 A, where as promoting compounds have been proposed sulfates rubidium and cesium.

Although previously suggested alkali metals, in General, more recent researchers in this area have considered the potassium, rubidium and cesium as the preferred alkali metals. See, for example, the number of patents Nielson et al. where these substances are used in small quantities and aasaigal together with silver (U.S. patent N 3952136; 4010115 and 4012425). Recently in this field have begun to emphasize the synergistic combinations of alkali metals. See, for example, the above-cited patent UK N 2043481 A and U.S. patents NN 4212772 and 4226782. In addition, in the art it is known that alkaline IU, 177169 and 4186106. In this area it is known that alkali metals can be applied before the silver is applied on the carrier (predsident) U.S. patent N 4207210; at the same time, when precipitated silver (soosazhdenie) - U.S. patents NN 4066575 and 4248741; or after deposition of silver (after besieged) patent of great Britain N 2045636 A.

In earlier work in this area has been proposed the use amount of the alkali metal in a very wide range. Often indicated that the alkaline metal can be applied in large quantities, for example, up to several percent. Later in this field in General it was found that small amounts of alkali metals provide the optimal effect, regardless of when it was besieged by the silver and alkali metals. Kilty in U.S. patent N 4207210 tied the optimum amount of an alkali metal with a specific surface area of the carrier. Exceptions to the above are the patents issued by the ICI, in which it is proposed to apply large quantities of only sodium (patent UK N 1560480) and a combination of potassium with small amounts of rubidium and cesium (U.S. patent N 4226782). However, in General it is accepted that the optimum can be found in much smaller amounts, the catalyst affects its characteristics. Differences in thermal conditions "reactivation" prove it. Additionally, it was found that the impregnating solutions and intermediate stages affect the final catalyst. For example Winnick in U.S. patent N 4066575 describes impregnating solution containing silver lactate, lactic acid, barium acetate, hydrogen peroxide and water. Class of catalysts based on lactate characterized by a very high stability, but low selectivity. The carrier impregnated with the solution and then activated by heating in an inert atmosphere at 350oC and then dried in air at 200oC for 12 hours "Activated catalyst is then impregnated with a solution of cesium and dried in air at 130oC for 3 hours Using an inert atmosphere during the stage of activation were obtained catalyst was more selective, but it is much less stable, i.e., the catalyst lost its activity rapidly, which resulted in a reduction of the operating time for a given edge of the working temperature.

Armstrong in U.S. patent N 4555501 described the use of an impregnating solution containing a silver salt of neocolony (polcanova acid). The impregnated carrier is then "activated" when is ikorodu, preferably the presence of a certain amount of oxygen. Then, if necessary, besieged alkali metal in a small amount (about 260 wt. hours per million by weight. hours).

Apparently, now the cesium is the preferred alkali metal. Well-known works in this field lists the various sources of cesium, for example, cesium hydroxide, cesium nitrate, cesium chloride, cesium chlorate, cesium bicarbonate, cesium carbonate and other anionic derivatives, such as formate, acetate and the like. In U.S. patent N 4374260 describes the coprecipitation of silver and cesium salt, such as carbonate of complex carboxylate silver/aminosidine.

U.S. patents NN 4350616 and 4389338 describe the application of CsCO3on the activated silver catalyst from the alcohol solution, where the silver was originally in an aqueous solution of silver salts. In the U.S. patents NN 4066575 and 4033903 retrieves a silver catalyst from aqueous and non-aqueous solutions of salts and subsequent processing of the activated silver catalyst by applying a salt of an alkali metal such as cesium, and anions of lower alcohol and preferably from aqueous alcohols. Similarly, in U.S. patent NN 4342667 describes the application CESA equipment, related to the application of an alkali metal, is a common interchangeability aqueous and non-aqueous methods, i.e., the silver catalyst can be obtained aqueous or nonaqueous techniques and the application of the alkali metal may be aqueous or nonaqueous. In addition, the silver salt or the alkali metal is not any specific (concrete). In General, methods tended preferred carrying out of reception in the presence of water.

Now found that water at any stage and in any quantity has a deleterious effect on the characteristics of the final catalyst. Thus this receipt is characterized essentially as anhydrous followed by deposition of an alkali metal such as cesium.

The advantage of the present invention in that they are catalysts with extraordinary stability when using them to obtain ethylene oxide, which have a high selectivity at high conversion in the method of producing ethylene oxide.

Summary of invention

Briefly stated, one object of the present invention is a catalyst obtained by the method of impregnation of porous media having a low specific surface area, the bath step by heating in the atmosphere, containing less oxygen than in air, for regulating the combustion of the organic part of the silver salt of the acid. The preferred sequence stage of activation, when the first stage is carried out at a temperature in the range from 150 to 200oC for less than one hour, preferably it is the first activation is carried out in an atmosphere containing less than about 20. % oxygen, the second stage is conducted by heating at a temperature in the range from more than 200oC to 300oC for less than one hour, the third stage is conducted by heating at a temperature in the range 300oC to 400oC and, finally, the fourth phase is conducted by heating at a temperature in the range of higher than 400oC to 500oC for less than one hour. Preferably each stage of heating is conducted for from 1 to 30 minutes the Atmosphere when heated regulate to eliminate uncontrolled combustion of the organic parts of silver salts or solvents by controlling and regulating the amount of oxygen present in the process of heating. Preferably, the atmosphere contains less than 3% vol. oxygen from the whole atmosphere. The activated receive media containing activated silver is Ernest in the range of 0.2-2.0 m2/g carbon with a solution of a silver salt of an organic acid. It was shown that the solution should not essentially contain both water and acid, as it is particularly beneficial effect on the catalytic properties and are therefore preferred. The impregnated carrier is activated by heating, and according to the invention regulate the combustion of organic materials.

For modification of the activated silver catalyst added alkali metal, preferably cesium.

Another object of the present invention is essentially anhydrous impregnation of the activated silver catalyst of alkali metal, preferably cesium, to obtain a treated catalyst by immersing the carrier in a stationary or circulating solution of an alkali metal in an anhydrous solvent, for example ethanol. To optimise the performance of the catalyst should choose the optimal amount of added alkali metal or metals, it will depend on the specific surface of a selected medium. That is, in the case of carriers, which have a higher specific surface area, it is necessary to apply more alkali metal than in the case of media, which is dehydrated means as far as possible, in any case, containing less than 1% water, i.e., essentially anhydrous.

The third object of the present invention is the washing of the modified caesium catalyst lowest alkanols. Preferably methanol, ethanol, isopropanol or similar alcohol is introduced into contact with the catalyst and impregnate it with alcohol, the catalyst, remove the alcohol from the catalyst and the catalyst is dried.

I believe that cesium ion in contact with the aluminum oxide of the media that does not contain silver, more strongly associated with the polar surface of the aluminum oxide than cesium on the surface of metallic silver. Described washing preferably Watervliet or washes away some of the less strongly bound caesium on silver, leaving the desired modifier cesium on sections of aluminum oxide.

The stability achieved by multi-stage heat activated silver catalyst, retain and increase selectivity by cooking it in anhydrous conditions, and final washing with solvent.

The catalyst of the present invention can be used in oxidizing conditions typical for this field of technology, to obtain okesutora.

The term "inert" as used in the present description, refers to any gaseous material that is activated does not react with silver or any other component impregnated with silver media. Preferred inert materials include nitrogen, helium and carbon dioxide, but can use other certain materials, including neon, argon, etc. limit the oxygen content in the process of activation is crucial.

Detailed description and preferred embodiment of the invention

The catalyst of the present invention may contain from 3 to 25 wt.% silver on the carrier. Preferred catalysts obtained in accordance with the present invention, contain from 3 to about 20 wt.% silver, counting on the metal deposited on the surface and all the pores of a porous refractory carrier. Now the silver content above 20 wt.% from the total mass of the catalyst, but such catalysts are unnecessarily expensive. Preferably, the silver content, counting on metal, about 5-13% of the total mass of the catalyst, particularly preferably silver content of 8-11%.

The catalysts can be produced with the use of media containing oxide aluminium - aluminum oxide, specifically the media containing up to about 15 wt.% silicon dioxide. Particularly preferred carriers have a porosity of about 0.1-1.0 cm3/g, preferably about 0.2-0.5 cm3/, Preferred carriers have a relatively low specific surface area, i.e., about 0.2-2.0 m2/g, preferably 0.4 to 1.6 m2/g, most preferably 0.5 to 1.3 m2/g, as determined by the method of the BET method of brunauer, Emmett and teller). Cm. J. A. Chem. Sc. 60, 309-16 (1938). Porosity determines the mercury Porosimeter; see Drake and Ritter, "Ind. Eng. Chem. Anal. Ed., 17, 787 (1945). The pore distribution and the pore size was determined on the basis of measurements of specific surface area and apparent porosity.

For use in the methods for producing ethylene oxide carriers preferably be molded in the form of particles of regular shape, for example, tablets, balls, disks, etc. it is Desirable that the applied carrier particles had an equivalent diameter in the range of 3-10 mm, preferably in the range of 4-8 mm, which are usually compatible with the internal diameter of pipe, in which is placed the catalyst. "Equivalent diameter" is the diameter of the sphere having the same relation to the outer surface (i.e., excluding the surface within the pores of the particles) to objektes in the solution, containing a silver salt of organic acid, which essentially does not contain water and organic acid, for example, polkanovaa acid (in particular, acid, having at least seven carbon atoms), described in U.S. patent N 4864042 which is recorded here in full. Containing silver liquid penetrates into the pores of the carrier by adsorption, capillary action and/or vacuum. You can apply a single dive or series of dives, with intermediate drying or without it, depending in part on the concentration of silver salts in solution. To obtain catalysts having silver content in the preferred range, suitable impregnating solutions should generally contain 5-50 wt. % silver, counting on the metal, but in the form of silver salts of organic acids. The exact applied concentration, of course, will depend, among other factors, the desired silver content, the nature of the medium, the viscosity of the liquid and the solubility of silver salts of organic acids.

Impregnation of a selected medium is achieved in the usual way. The material of the carrier is kept in a solution of silver up until the entire solution is not absorbed by the media. Preferred kolichestvennie pore size of the porous media.

Impregnating solution, as already indicated, is characterized as essentially not water-containing and not containing the organic acid solution of silver salt of organic acid. Apply a hydrocarbon solvent such as toluene, cyclohexane, xylene, ethylbenzene, cumene or none, which usually should not contain water. Because I believe that water has a harmful influence on getting the silver catalysts when using the method of the present invention, it should be present in the silver impregnating solution in an amount of not more than about 0.1 vol.%, preferably less than about 0.01 vol.%.

After multistage activation device can optionally be impregnated with an alkaline metal. The purpose of impregnation with an alkaline metal is a modification of the catalyst and increase selectivity while maintaining high stability. After impregnation, the amount of alkali metal on the treated catalyst is usually close to the number used so far. Thus inflicted a number in General, should be up to about 810-3g-EQ/kg of catalyst, preferably up to about 710-3g-EQ/kg, about 1-610-3g-EQ/kg (g-EQ is the mass in grams-Aqua of the present invention preferred the last three alkali metal, in particular cesium, although can not exclude sodium and lithium. Alkali metal salts are dissolved in alcohol solution, preferably essentially not containing water.

In the absence of water, an alcohol solvent, the compound of cesium, although it is poorly soluble, remains uniformly distributed in the solvent during evaporation and drying, so it is more evenly distributed around the silver catalyst. Preferably impregnated with an alkaline metal catalysts quickly dried, for example within 1-2 minutes at high temperature, for example at a temperature of from at least 100oC up to 800oC, preferably about 200-600oC. This can easily be achieved by applying a moving tape, as described in this application, or by placing it in the tube and quickly passing through it a stream of hot air to remove solvent. Drying can be carried out in air or inert gas.

The catalysts obtained by the above methods have improved characteristics, in particular, stability, when used to obtain ethylene oxide vapor-phase oxidation of ethylene with molecular oxygen. This obtaining is usually carried out at a temperature rodnye mixture of reagents contain from 0.5 to 20% of ethylene and from 3 to 15% oxygen, the remainder of the mixture is a relatively inert materials, including substances such as nitrogen, carbon dioxide, methane, ethane, argon and the like. Usually only a portion of the ethylene reacts to a single pass over the catalyst, and after the separation of ethylene oxide, which is the target product, and delete the appropriate flow of exhaust gases and carbon dioxide to prevent uncontrolled formation of inert ingredients and/or by-products, unreacted materials are returned to the oxidation reactor.

In the following examples, the catalysts produced using the solution in cumene silver salt neodecanoic acid, as described above. Characteristics of suitable carriers are presented below.

The finished catalyst is then tested on the activity and selectivity by crushing and loading attachment 36 g microreactor consisting of a tube size of 6.3 mm stainless steel, which is heated in a salt bath. Raw mix 7% oxygen, 5% CO215% OF C2H470% OF N2passed over the catalyst at a volumetric rate of gas 5500 h-1. Pressure support 300 psig (21,69 ATM) and a temperature between 200 and 300oC, when triballistic characterize temperature, necessary to maintain the concentration of ethylene oxide at the outlet of 1.50%. The lower the temperature, the more active the catalyst. The selectivity of the catalyst is expressed as mol.% the total number of ethylene converted to ethylene oxide at concentrations of ethylene at the output of 1.50%. The stability of the catalyst is determined by dividing the temperature gradient at its rising, required to maintain the content of ethylene oxide 1,50%, 100 h and expressed asoC/100 h

Example 1 (comparative)

This example was performed conventional activated by applying an aqueous cesium.

The media used for this receipt, obtained from Norton company, it was made mainly of aluminum oxide in the form of cylinders with a size of 7.9 mm, the Carrier has a specific surface area of 0.55 m2/g, pore volume of 0.3 cm3/g and an average pore diameter of 1.5 μm, 95 including solution neodecanoate silver cumene containing 26 wt.% silver, were added to 225 hours of hot carrier and the mixture was stirred for 20 minutes, the Catalyst was obtained using one-step activation air at 500oC and was soaked with a solution of cesium hydroxide in a solvent of water/alcohol, which was then removed in vacuum. The catalyst espitia reaction was 232oC. characteristics of the catalyst did not improve with increasing reaction time.

Example 2

In this example, the multistage activation was performed applying anhydrous Cs.

Used to do this, obtain the media received from the company Norton, it was made mainly of aluminum oxide in the form of cylinders with a size of 7.9 mm Carrier had a specific surface area of 0.55 m2/g, pore volume of 0.3 cm3/g and an average pore diameter of 1.5 μm, 95 including solution neodecanoate silver cumene containing 26% of silver, were added to 225 hours of hot carrier and the mixture was stirred for 20 minutes Application of silver compounds induced by heating the catalyst to a temperature which did not exceed 200oC in a stream of nitrogen. The residence time of the catalyst in moving the ribbon in the heated zone was 2 minutes This stage was repeated at 300 and 400oC.

The catalyst was then soaked for two hours at room temperature with a solution (anhydrous ethanol), containing 525 hours million hours of cesium bicarbonate. The catalyst surface was dried by a stream of nitrogen and then heated on a moving belt at 200oC. the test Results of the catalyst are summarized in table. 1 (see the end of the description).

Note - alumina in the form of cylinders with a size of 7.9 mm The carrier has a specific surface area of 0.55 m2/g, pore volume of 0.3 cm3/g and an average pore diameter of 1.5 μm. A portion of the carrier 225 g were heated to 80oC and placed in a vacuum of 50 mm RT.art., then added 95 including solution neodecanoate silver cumene containing 26% of silver, and the mixture was stirred for 20 minutes the Precipitation of silver compounds induced by heating the catalyst to a temperature which does not exceed 200oC in a stream of nitrogen, the residence time of the catalyst in the heated zone was 2 minutes This stage was repeated at 300oC and 400oC.

The catalyst was then soaked for 2 h at room temperature in anhydrous solution in ethanol, which contains 525 hours million hours of cesium bicarbonate. The catalyst was dried on a moving belt at 200oC. the test Results of the catalyst are summarized in table. 2 (see the end of the description).

Example 4

Used to do this, obtain the media received from the company Norton, it was made mainly of aluminum oxide in the form of cylinders with a size of 7.9 mm Carrier had a specific surface area of 0.55 m2/g, pore volume of 0.3 cm3/g and an average pore diameter of 1.5 μm, 95 including solution neodecanoate silver cumene containing 26% of silver, were added to 225 hours by Goryacheva catalyst until the temperature of decomposition of silver salts. This was achieved by heating in an oven that has multiple heating zones, in a controlled atmosphere. The catalyst was loaded on a moving line, which came in a furnace at room temperature, then gradually increase the temperature by passing catalyst from one zone to the next. The temperature was increased up to 400oC by passing the catalyst through seven heating zones. After heating zones tape was passed through a cooling zone, where the catalyst was slowly cooled to a temperature below 100oC. the Total residence time in the furnace was 22 minutes the Atmosphere in the furnace is regulated to prevent uncontrolled combustion of the organic part of the silver salt and the solvent. This was achieved by applying a stream of nitrogen in the different heating zones. The amount of nitrogen was sufficient for inhibition of any of combustion and to remove any allocated smoke during calcination.

The catalyst was then soaked for two hours at room temperature in anhydrous solution in ethanol containing 525 hours million hours of cesium bicarbonate. The solution was removed and added to an equal volume of ethanol. The catalyst was mixed with fresh ethanol to remove excess cesium present n the heated zone of the furnace in a stream of air at 200oC. the residence Time in the hot zone, the air flow and oven temperature were sufficient to remove all solvent for the shortest possible time. The catalyst was crushed and loaded into the tube, which was heated salt bath. A gaseous mixture containing 15% ethylene, 7% oxygen and 78% inert component, composed primarily of nitrogen and carbon dioxide was passed over the catalyst at 21, 09 ATM. The reaction temperature was regulated to achieve the capacity of 160 kg of ethylene oxide/h/m3of the catalyst. The test results of the catalyst are summarized in table. 3 (see the end of the description).

Example 5

Used to do this, obtain the media received from the company Norton, it was made mainly of aluminum oxide in the form of cylinders with a size of 7.9 mm Carrier had a specific surface area of 0.55 m2/g, pore volume of 0.3 cm3/g and an average pore diameter of 1.5 μm. Added 95 including solution neodecanoate silver cumene containing 26% of silver, to 225 hours of hot carrier and the mixture was stirred for 30 minutes Deposition of silver induced by heating the catalyst to a temperature which does not exceed 150oC in a stream of nitrogen. The residence time of the catalyst in the heated zone was 2 minutes begins two hours at room temperature in anhydrous solution in ethanol, containing 525 hours million hours of cesium bicarbonate. The solution was removed and added to an equal volume of ethanol. The catalyst was mixed with fresh ethanol to remove excess cesium present on its surface. The liquid was removed and the catalyst was dried by placing on the tape that is moved through the heated zone of the furnace in a stream of air at 200oC. the residence Time in the hot zone, the air flow and oven temperature were sufficient to remove all solvent for the shortest possible time.

After drying, the catalyst was tested in the tube, which was heated salt bath. A gaseous mixture containing 15% ethylene, 7% oxygen and 78% inert component, composed primarily of nitrogen and carbon dioxide was passed over the catalyst at 21,09 ATM. The reaction temperature was regulated to achieve the performance 160 kg of ethylene oxide/h/m3of the catalyst. The test results of the catalyst are summarized in table. 4 (see the end of the description).

Example 6

Used to do this, obtain the media received from the company Norton, it was made mainly of aluminum oxide in the form of cylinders with a size of 7.9 mm Carrier had a specific surface area of 0.55 m2/g, pore volume of 0.3 cm3/g ICH. hot carrier and the mixture was stirred for 20 minutes Deposition of silver induced by heating the catalyst to a temperature which does not exceed 150oC, the flow of gaseous mixture containing 2.5% oxygen in nitrogen. The residence time of the catalyst in the heating zone was two minutes. This process was repeated at 200, 250 and 300oC and at 400oC.

The catalyst was then soaked for two hours at room temperature in anhydrous solution in ethanol containing 525 hours million hours of cesium bicarbonate. The catalyst was dried and tested in the tube, which was heated salt bath. A gaseous mixture containing 15% ethylene, 7% oxygen and 78% inert component, composed primarily of nitrogen and carbon dioxide was passed over the catalyst at 21,09 ATM. The reaction temperature was regulated to achieve the capacity of 160 kg of ethylene oxide/h/m3of the catalyst. The results are summarized in table. 5 (see the end of the description).

Example 7

Used to do this, obtain the media received from the company Norton, it was made mainly of aluminum oxide in the form of cylinders with a size of 7.9 mm Carrier had a specific surface area of 0.55 m2/g, pore volume of 0.3 cm3/g and the average diameter and the calf and the mixture was stirred for 20 minutes The deposition of silver was induced by heating the catalyst in a stream of nitrogen.

The catalyst was divided into several equal portions. Each portion was soaked for 2 h at room temperature in a solution of ethanol, which had a certain concentration of water contained 525 hours million hours of cesium bicarbonate. The liquid was removed and the catalyst was heated on a moving belt in a stream of air at 200oC.

A sample of the catalyst was tested in the tube, which was heated salt bath. A gaseous mixture containing 15% ethylene, 7% oxygen and 78% inert component, composed primarily of nitrogen and carbon dioxide was passed over the catalyst at 21,09 ATM. The reaction temperature was regulated to achieve the capacity of 160 kg of ethylene oxide/h/m3of the catalyst. The results are summarized in table. 6 ( see the end of the description).

Example 8

The method used for drying of solvent is important for the characterization of the catalyst. After impregnation with a solution of cesium is very important precipitated salt of cesium on the catalyst as quickly as possible. It was found that the removal of the solvent in a stream of hot gas, such as heated air, is one of the effective ways to achieve the b the I the salt of cesium. Drying of the catalyst with a lower speed, for example in a vacuum or by means of a gas flow with a low temperature leads to the decrease in the intensity of deposition of caesium and does not provide the full effect of the promoter. The following examples will illustrate the influence of the drying method.

Industrial the resulting carrier of alumina was impregnated with a solution of neodecanoate silver cumene and then progulivali impregnated mass at 500oC in a stream of nitrogen. This mass was divided into portions of 245 g and each portion was soaked for 2 h in 300 g of a solution in ethanol containing 525 hours million hours of cesium. The crude catalyst was dried using different methods. Table. 7 illustrates the effect of different salts of cesium and method of drying on the characteristics of the catalyst (see the end of the description).

Example 8A illustrates the effects as anhydrous salts of cesium and quick drying. Example 8B is a standard case in which the solution of cesium was not anhydrous and the catalyst was dried by storage at temperatures below the 50oC under reduced pressure, 100 mm RT. Art., for 17 hours Example 8C is similar to example 8B, except that the applied method is quick drying.

Example 9

Prymenav the form of cylinders with a size of 7.9 mm The carrier had a specific surface area of 0.55 m2/g, pore volume of 0.3 cm3/g and an average pore diameter of 1.5 μm, 95 including solution neodecanoate silver cumene containing 26% of silver, were added to 225 hours of hot carrier and the mixture was stirred for 30 minutes Deposition of silver induced by heating the catalyst to a temperature which does not exceed 500oC in a stream of nitrogen. The residence time of the catalyst in the heated zone was two minutes.

The catalyst was then soaked for two hours at room temperature in anhydrous solution in ethanol containing 525 hours million hours of caesium chloride. The solution was removed and added to an equal volume of ethanol. The catalyst was mixed with fresh ethanol to remove excess cesium present on its surface. The liquid was removed and the catalyst was dried by placing on the tape that is moved through the heating zone of the furnace in a stream of air at 200oC. the residence Time in the hot zone, the air flow and oven temperature were sufficient to remove all solvent for the shortest possible time.

After drying, the catalyst was tested in the tube, which was heated salt bath. A gaseous mixture containing 15% ethylene, 7% oxygen and 78% inert lump is round reactions were regulated, to achieve the capacity of 160 kg of ethylene oxide/h/m3of the catalyst. The test results of the catalyst are summarized in table. 8 (see the end of the description).

Example 10

Used to do this, obtain the media received from the company Norton, it was made mainly of aluminum oxide in the form of cylinders with a size of 7.9 mm Carrier had a specific surface area of 0.55 m2/g, pore volume of 0.3 cm3/g and an average pore diameter of 1.5 μm, 95 including solution neodecanoate silver cumene containing 26% of silver, were added to 225 hours of hot carrier and the mixture was stirred for 30 minutes Deposition of silver induced by heating the catalyst to a temperature which does not exceed 200oC in a stream of nitrogen. The residence time of the catalyst in the heating zone was two minutes. This operation is repeated at 300 and 400oC.

The catalyst was then soaked for two hours at room temperature in anhydrous solution in ethanol containing 525 hours million hours of cesium carbonate. The liquid was removed and the catalyst was dried by placing on the tape that is moved through the heated zone of the furnace in a stream of air at 200oC. the residence Time in the hot zone, the air flow and oven temperature were sufficient to adeleke, which was heated salt bath. A gaseous mixture containing 15% ethylene, 7% oxygen and 78% inert component, composed primarily of nitrogen and carbon dioxide was passed over the catalyst at 21,09 ATM. The reaction temperature was regulated to achieve the capacity of 160 kg of ethylene oxide/h/m3of the catalyst. The test results of the catalyst are summarized in table. 9 (see the end of the description).

Example 11

Used to do this, obtain the media received from the company Norton, it was made mainly of aluminum oxide in the form of cylinders with a size of 7.9 mm Carrier had a specific surface area of 0.55 m2/g, pore volume of 0.3 cm3/g and an average pore diameter of 1.5 μm, 95 including solution neodecanoate silver cumene containing 26% of silver, were added to 225 hours of hot carrier and the mixture was stirred for 30 minutes

The deposition of silver was induced by heating the catalyst up to the temperature of decomposition of silver salts. This was achieved by heating in an oven that has multiple heating zones, in a controlled atmosphere. The catalyst was loaded on a moving tape, which came in a furnace at room temperature, which gradually increased with the passage of catalysate seven heating zones. After heating zones tape was passed through a cooling zone, where the catalyst was slowly cooled to a temperature below 100oC. the Total residence time in the furnace was 22 minutes the Atmosphere of the furnace was regulated to prevent uncontrolled combustion of the organic part of the silver salt and the solvent. This was achieved by applying a stream of nitrogen in the different heating zones. The amount of nitrogen was sufficient for inhibition of any of combustion and to remove any allocated smoke during calcination.

The catalyst was then soaked for two hours at room temperature in anhydrous solution in ethanol containing 525 hours million hours of cesium bicarbonate. The catalyst was dried and tested in the tube, which was heated salt bath. A gaseous mixture containing 15% ethylene, 7% oxygen and 78% inert component, composed primarily of nitrogen and carbon dioxide was passed over the catalyst at 21,09 ATM. The reaction temperature was regulated to achieve the capacity of 160 kg of ethylene oxide/h/m3of the catalyst. The test results of the catalyst are summarized in table. 10 (see the end of the description).

1. A method of obtaining a silver catalyst on the carrier for vapor oxide is 2.0 m2/g hydrocarbon solution of a silver salt of organic acid taken in the quantity sufficient for the application of from 3 to 25 wt.% silver on the carrier, the activation of the impregnated carrier and the impregnated absorbent carrier impregnated with silver salt solution of an alkali metal content in the catalyst is from 1 to 6 to 10-3g-EQ. alkali metal per 1 kg of catalyst, characterized in that the activation is carried out by heating in the first stage at a temperature in the range from 150 to 200oC for less than 1 h, in a second stage at a temperature in the range from more than 200 to less than 300oC for less than 1 h, in the third stage at a temperature in the range from 300 to less than 400oC for less than 1 h, in the fourth stage at a temperature of from 400 to 500oC during 1 h in an inert atmosphere containing one or more inert gases, and the impregnated impregnated with silver media perform essentially anhydrous alcoholic solution containing a compound of an alkali metal.

2. The method according to p. 1, wherein the inert atmosphere is essentially nitrogen.

3. The method according to p. 1, wherein the inert atmosphere is essentially carbon dioxide.

6. The method according to p. 1, characterized in that the heating of the impregnated carrier at the second stage activation is conducted for from 1 to 30 minutes

7. The method according to p. 1, characterized in that the heating of the impregnated carrier at the third stage of activation is conducted for from 1 to 30 minutes

8. The method according to p. 1, wherein the inert atmosphere is essentially helium.

9. The method according to p. 1, wherein the silver salt is a silver salt of neocolony.

10. The method according to p. 1, characterized in that the alkali metal is cesium.

11. The method according to p. 1, characterized in that it is cesium carbonate.

12. The method according to p. 1, characterized in that it has a cesium bicarbonate.

13. The method according to p. 2, characterized in that the alkaline solution is an anhydrous alkaline solution.

14. The method according to p. 2, characterized in that it is cesium carbonate.

15. The method according to p. 2, characterized in that it has a cesium bicarbonate.

16. The method according to p. 1, characterized in that the number specified uglevodorodnaya fill the pore volume of the specified porous media.

17. The method according to p. 10, characterized in that it further includes flushing impregnated with cesium silver catalyst alcoholic solution and drying.

18. The method according to p. 17, characterized in that additionally carry out some alcohol washes.

19. The method according to p. 17, characterized in that the catalyst is dried quickly.

20. The method of producing ethylene oxide by oxidation of ethylene with molecular oxygen at a temperature of 150 to 450oC and pressure in the presence of a silver catalyst obtained by impregnation of a porous carrier having a specific surface area of from 0.2 to 2.0 m2/g hydrocarbon solution of a silver salt of neocolony sufficient to secure from 3 to 20 wt.% silver on the carrier, activation impregnated with silver media and impregnation of the activated carrier with a solution of a salt of an alkali metal content of from 1 to 6 to 10-3g-EQ. alkali metal per 1 kg of catalyst, characterized in that the activation is carried out in an atmosphere containing less oxygen than does air, by heating in the first stage at a temperature in the range from 150 to 200oC for less than 1 h, in a second stage at a temperature in the range from more than 200 to less than 300ooC during 1 h, the impregnated activated carrier perform essentially anhydrous alcoholic solution containing a compound of an alkali metal, and oxidation of ethylene is carried out at a pressure of 0.49 - 34,61 ATM.

21. The method according to p. 20, characterized in that the quantity of hydrocarbon solution of a silver salt used for the impregnation of porous media, not more than necessary to fill the volume of pores of this porous media.

22. The method according to p. 20, wherein the alkali metal is cesium.

23. The method according to p. 22, characterized in that the cesium is contained essentially in the anhydrous alcohol solution.

24. The method according to p. 23, characterized in that the saturated cesium silver catalyst is washed with an alcohol solution and dried.

25. The method according to p. 24, characterized in that conduct several alcohol rinses.

26. The method according to p. 20, characterized in that the first stage of activation is carried out in an atmosphere containing less than 20 vol.% the oxygen.

27. The method according to p. 26, wherein the activation is performed on a moving belt.

28. The method according to p. 27, characterized in that the time vyderzhivaniya fact, the time-keeping impregnated carrier at the second stage of activation is from 2 to 30 minutes

30. The method according to p. 27, characterized in that the time-keeping impregnated carrier at the third stage of activation is from 2 to 30 minutes

31. The method according to p. 26, characterized in that the atmosphere is essentially nitrogen.

32. The method according to p. 26, characterized in that the atmosphere is essentially carbon dioxide.

33. The method according to p. 26, characterized in that the atmosphere is essentially helium.

34. The activation method of a silver catalyst on the carrier for vapor-phase oxidation of ethylene to ethylene oxide, comprising impregnating a porous support having a specific surface area of from 0.2 to 2.0 m2/g hydrocarbon solution of a silver salt of organic acid taken in the quantity sufficient for the application of from 3 to 20 wt.% silver on the carrier, the activation of the impregnated carrier by heating and impregnation of absorbent carrier impregnated with silver, a solution containing compounds of alkali metal content in the catalyst is from 1 to 6 to 10-3g-EQ. alkali metal per 1 kg of catalyst, characterized in that as a solution containing soeiety.

 

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