JP2002519399A - Process for producing aliphatic diacid and nitrous oxide - Google Patents

Abstract

  (57) [Summary] Aliphatic diacids and nitrous oxides produced by the following method: producing an aliphatic dibasic acid by oxidizing a hydroxylated aromatic compound with nitrous oxide to form an aliphatic dibasic acid, NOx An aliphatic diacid is produced using nitrous oxide and ammonia formed by reducing a mixture of gas streams containing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] The present invention relates to the production of nitrous oxide. The present invention relates to the use of nitrous oxide prepared for the hydroxylation of aromatic compounds. The invention also relates to the purification of a gas stream containing nitrous oxide and its subsequent use in the above-mentioned hydroxylation process.

BACKGROUND OF THE INVENTION Pure nitrous oxide (N ₂ O) is used in medicine as an anesthetic gas, as an oxidant in various fuels, and as a cleaner in semiconductor manufacturing. Recently, a new use for nitrous oxide diluted with molecular nitrogen (often as an available inert gas) has been found. Nitrous oxide is used as a mild oxidizing agent to produce various hydroxylated hydrocarbons. However, this manufacturing technique is demanding with regard to the content of other strong oxidants such as, for example, oxygen, nitric oxide (NO) and nitrogen dioxide (NO ₂ ) which can be present in the nitrous oxide as a mixture.

A known method for producing nitrous oxide is with ammonium nitrate (NH ₄ NO ₃ ), with a melt decomposition temperature of 220 to 250 ° C. (see USSR author license No. 1097556). .
However, this method is difficult to control due to the high potential for spontaneous degradation. Therefore, a high-capacity unit cannot be easily constructed, and therefore, nitrous oxide cannot be produced on a large scale. In addition, ammonia nitrate is very expensive, thus increasing the cost of producing nitrous oxide. An additional source of nitrogen is required to obtain a significant amount of nitrogen-diluted nitrous oxide.

A method for producing nitrous oxide based on selectively oxidizing ammonia (NH ₃ ) with oxygen molecules (O ₂ ) at 200 to 500 ° C. under a pressure of 20 atm under various metal oxide catalysts has also been proposed. is there. Because these methods use inexpensive raw materials,
Manufacturing costs are low. It is a safer way to do more large-scale factory production.

For example, according to a method for producing nitrous oxide by selective ammonia oxidation (Japanese Patent Application No. 46-33210), a reaction gas mixture containing ammonia and molecular oxygen is passed through a catalyst bed to form nitrous oxide and nitrogen oxide. Produces a gas mixture containing water vapor, molecular oxygen and molecular nitrogen. After cooling and water condensation, the gas mixture is split into two. One stream is returned to the inlet reaction mixture and another stream is subjected to a separation step to provide pure nitrous oxide. In that method, the ammonia concentration does not exceed 10 to 15% by volume in order to avoid the ammonia-oxygen explosion zone. The resulting reaction product gas mixture is a mixture of nitrogen oxides, nitrogen dioxide (eg, NOx) and oxygen (which is a stronger oxidizing agent than nitrous oxide and is therefore undesirable for the production of hydroxylated hydrocarbons). Contains significant amounts.

In another method (Japanese Patent Application No. 6-122505), an inlet reaction gas mixture containing ammonia, molecular oxygen and water vapor is passed over or through a catalyst bed to produce nitrous oxide, molecular oxygen, released ammonia, molecular nitrogen. , A reaction product gas mixture containing nitrogen oxides (NOx) and water vapor. The released ammonia and water are cooled and condensed and returned to the inlet reaction mixture. Thus, if more than 50% by volume of water vapor is present in the reaction mixture and the reaction product is condensed from the gas phase, it is recycled. Dilution of the reaction mixture with steam in this way increases the selectivity for nitrous oxide and increases the concentration in the final product. The addition of water also increases the lower limit of the ammonia explosion zone and increases the safety of the method.

[0007] A major drawback of the above-mentioned process is that it consumes a lot of energy for cooling and condensing and evaporating the ammonia solution, thus increasing the production cost of nitrous oxide. It should be noted that more energy is required for condensation and evaporation since more than 50% by volume of water must be present in the reaction mixture to ensure safety from explosion. To reduce the content of nitrogen oxides mixtures in the final product of the process, from 0.5 oxygen / ammonia volume ratio in the reaction mixture in a highly selective CuO-MnO ₂ catalyst bed inlet Keep within 1.5. If any other highly selective catalyst is used, this method will not provide the desired results.

[0008] US Patent Nos. 5055523; 5001280 and 5110995, the contents of which are incorporated herein by reference, describe the use of nitrous oxide to hydroxylate aromatic compounds to give aromatic alcohols (eg, phenols). ing. However, the cost of nitrous oxide for such hydroxylation depends on conventional phenol production techniques (eg, John Wiley & Sons).
, Kirk-Othmer Encyclopedia of Chemica
The cost is very high compared to the 1st Technology, 3rd edition, 17: 374-377 (1982)).

In the production of diacids, nitrous oxide, NOx, CO ₂ , CO, N ₂ low boiling organic compounds,
And a waste gas stream containing other gases. Heretofore, the separation and purification of nitrous oxide from waste gas streams for applications other than extremely pure nitrous acid for medical purposes has been too costly, and therefore, in diacid waste gas streams. No nitrous oxide was recovered. The nitrous oxide present in waste gas streams is either discharged, decomposed, or recycled to form nitric acid. Thus, the use of nitrous oxide from diacid waste gas streams, including the hydroxylation of aromatics, has never been considered before.

[0010] Therefore, there is a need for a process for producing nitrous oxide on a large scale, economically, safely and with high yield and high conversion.

There is a further need to provide an economical method of producing phenolic compounds commercially while producing other desirable chemical intermediates.

SUMMARY OF THE INVENTION The present invention utilizes ammonia oxidation to reduce energy consumption to a very low level while limiting the content of nitrogen oxides (NOx) and oxygen in the final nitrous oxide product gas stream. It is a method of manufacturing.

The present invention also relates to a method for recovering and purifying nitrous oxide present in various NOx containing gas streams by converting NOx to nitrous oxide by ammonia oxidation.

The present invention provides: hydroxylating an aromatic compound with nitrous oxide in a reactor to form a phenolic compound; reducing the phenolic compound to form a cycloaliphatic ketone and / or alcoholic compound. Forming; oxidizing a cycloaliphatic ketone and / or alcoholic compound to form an aliphatic diacid compound and a nitrous oxide gas stream; reacting the nitrous oxide gas stream to a purified nitrous oxide gas stream. And recycling the purified nitrous oxide gas stream to the reactor.

The present invention also provides: supplying a reaction mixture comprising a gas stream containing ammonia and NOx to a reactor; and oxidizing ammonia and reducing NOx to form a product gas stream of nitrous oxide. A process for producing nitrous oxide from a NOx-containing gas stream.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention comprises hydroxylating an aromatic compound with nitrous oxide to form a phenolic compound; reducing the phenolic compound to form a cycloaliphatic ketone / alcoholic Forming a compound and oxidizing the cycloaliphatic ketone / alcoholic compound to form an aliphatic diacid compound and a nitrous oxide gas stream; reacting the nitrous oxide gas stream to produce purified nitrous oxide gas Providing a stream; and recycling the purified nitrous oxide gas stream to the hydroxylation step to produce an aliphatic diacid (eg, adipic acid, glutaric acid, succinic acid, oxalic acid, etc.).

As described in US Pat. Nos. 5,110,995; 5,672,777; and 5,756,861 (the contents of which are incorporated herein by reference), the aromatic nucleus is directly oxidized using nitrous oxide over a zeolite catalyst to form the aromatic compound. Perform hydroxylation.

For example, a mixture of benzene and nitrous oxide is contacted with a catalyst in a reactor under conditions selected to oxidize benzene to phenol. The molar ratio of nitrous oxide to benzene in the mixture may be less than 0.5. If the ratio of nitrous oxide to benzene is sufficiently low, a reaction selectivity for phenol of at least 90 mol% benzene is obtained. By "obtaining reaction selectivity" is meant that by reducing the molar ratio of nitrous oxide to benzene, the selectivity of benzene to phenol obtained with a given reaction condition and catalyst is the highest. I do. With the preferred catalyst at normal reaction temperatures, the selectivity obtained typically approaches or reaches a ratio of nitrous oxide to benzene of about 0.1. Downstream of the reactor, unreacted benzene can be separated from the product by conventional separation techniques,
Recyclable to reactor.

The mixture of nitrous oxide, benzene and any inert gas used in the reactor (benzene-nitrous oxide reaction mixture) may contain at least 0.3 mol% of nitrous oxide. Low amounts tend to limit productivity. By choosing the proportion of the mixture in the reactor, the adiabatic temperature rise due to the exothermic reaction can be limited to 150 ° C. or less. If this is done, the reaction can be performed adiabatically without unduly increasing the undesired product and without using expensive heat exchange means. Increasing the inert gas or benzene content of the mixture for temperature control also reduces the flammability of the mixture.

This method is usually carried out in a temperature range from 250 to 600 ° C. High temperatures result in the formation of undesirably high levels of by-products, while low temperatures result in unduly low reaction rates even at the highest catalyst loadings. However, any temperature that does not form excess by-products and provides acceptable reaction rates can be used. Any catalyst that is effective for the partial oxidation of benzene or a benzene-substituted product to phenol or a phenol-substituted product can be used. For example, vanadium (V) oxide on silica or various zeolites can be used. Preferred catalysts include acidified ZSM-5 and ZSM-11 which contain a catalytically effective amount of iron. Further, the productivity of this method can be increased by using a zeolite that has been reacted with hot water by exposing it to water vapor in air at about 500-900 ° C. for 2 hours. Such reactions are described in U.S. patent application Ser. No. 08 / 419,361, filed Apr. 10, 1995 and co-pending, the disclosure of which is incorporated herein by reference.

In general, the benzene selectivity for phenol (the number of moles of phenol formed per mole of benzene reacted) is maximized; the selectivity of nitrous oxide for phenol (phenol formed per mole of nitrous oxide reacted) The process is operated to maximize productivity (mass of phenol per unit time divided by mass of catalyst); and to minimize the loss of catalyst activity. (The yield of nitrous oxide or benzene over phenol is usually somewhat lower than selectivity due to loss of material in the system.) The primary reaction to convert benzene to phenol is a variety of side reactions: benzene to coke It involves the conversion reaction of benzene to carbon dioxide and carbon monoxide; and the conversion reaction of benzene to various partially oxidized aromatics such as dihydroxybenzene.

It will be appreciated that other than the ratios of the feed components, the aforementioned variables are not irrelevant. For example, increasing the feed temperature will increase the reaction rate and increase the conversion of nitrous oxide, thereby increasing the reactor outlet temperature. Also, due to increased conversion, the average concentration of nitrous oxide in the reactor decreases. The yield of nitrous oxide relative to phenol depends on whether the benefits from low concentrations of nitrous oxide are greater or less than the disadvantages due to high temperatures. Similarly, productivity depends on whether the decrease in selectivity is compensated for by an increase in nitrous oxide conversion.

The phenol obtained from the above reaction is hydrogenated to form a mixture of cyclohexanol and cyclohexanone (commonly referred to as KA oil). This type of reaction is described in UK Patent Nos. 1063357; 1257607; 1316820; 147185.
And U.S. Pat. Nos. 3,932,514; 3,988,884; 4,053,524; 4.
092360; 4162267; 4164515; 4200553; 42039
23; 4283560 and 4272326, the contents of which are incorporated herein by reference.

In one embodiment, the KA oil is produced by selective hydrogenation of phenol in the gas phase in the presence of a palladium-containing catalyst, comprising 0.3 to 5% by weight palladium on τ-aluminum oxide. In the presence of a catalyst, the catalyst also contains from 2 to 60% by weight of alkaline earth hydroxide (based on total catalytic material);
The reaction is carried out at a temperature of 0 ° C.

Catalysts containing calcium hydroxide as alkaline earth hydroxide have been found to be particularly effective.

The catalyst to which the present invention relates is to form τ-Al ₂ O ₃ and an alkaline earth hydroxide together, impregnate the formed catalyst pellets or catalyst body with an aqueous palladium chloride solution or a palladium nitrate solution, It is preferably produced by reducing it with hydrogen.

The process comprises reacting the phenol vapor and hydrogen at a reaction temperature of 120 to 170 ° C. at atmospheric pressure or at a pressure of 1: 5 to 1:50, preferably 1:10 to 1:25, in a reaction tube. The process is carried out continuously through a catalyst charged in the reactor, in which a phenol extrusion rate of 0.15 to 30 kg per liter of catalyst per hour is maintained. The reaction product contains 92 to 96% of cyclohexanone, 2 to 4% of cyclohexanol and some% of unconverted phenol.

The KA oil obtained above is reacted with nitric acid to form adipic acid. This type of reaction is known and is described, for example, in U.S. Patent Nos. 4,423,018;
329712; and 3186952, the contents of which are incorporated herein by reference. Such a reaction produces, in addition to the desired adipic acid, nitrous oxide which is recycled to the benzene oxidation reaction. The nitrous oxide obtained in this reaction often contaminates more than 10% by weight of NX. High levels of NOx have been found to be detrimental to the process of converting benzene to phenol. Therefore, the nitrous oxide recycled for the reaction of benzene to phenol should not contain more than 2% by volume of NOx, preferably less than 1% by volume, more preferably less than 0.1% by volume. . The desired purity of the recycle gas stream can be achieved by adjusting the KA oxidation to minimize NOx formation and diluting with a recycle gas stream containing high purity nitrous oxide. However, such techniques are economically disadvantageous and impractical. Therefore, it is preferred to operate the nitrous oxide gas stream from the adipic acid method to reduce the NOx content.

NOx can be removed by a known method. Such a method is described, for example, in US Pat.
689212; 4507271; 5030436 and Japanese Patent Publication 5-139.
710; 7-122505: and 6-122507, the contents of which are incorporated herein by reference.

However, the method of the invention described below is particularly preferred. The process of the present invention is not only a generally excellent and economical NOx removal process, but also produces the additional nitrous oxide required for subsequent hydroxylation of benzene to phenol.

For example, the present invention provides for the direct production of nitrous oxide with low energy consumption and limited nitrogen oxide and oxygen content.

[0032] One embodiment of the present invention is a method for producing nitrous oxide by reacting a NOx-containing gas stream; providing a reaction mixture comprising ammonia and a NOx-containing gas stream to a reactor. Oxidizing ammonia and reducing NOx to form a nitrous oxide product gas stream.

In the method of the present invention, the removal of NOx from the NOx-containing gas is carried out separately from the production of nitrous oxide, or the production of nitrous oxide is carried out in the same reactor / method as described herein before. Can be done simultaneously. Furthermore, nitrous oxide production can be performed separately from NOx removal as an independent method.

According to one embodiment of the method of the present invention, a reaction mixture gas stream containing molecular oxygen, molecular nitrogen, ammonia and water vapor is fed to a reactor catalyst bed for oxidizing ammonia with oxygen, The selectivity of the catalyst for nitric oxide is over 80%. The reaction gas product formed in the bed contains mainly nitrous oxide, nitrogen and water vapor. A portion (eg 25-89%) of the product gas stream is then separated at a temperature higher than the temperature of the water condensation (ie 5 ° C. to 450 ° C., preferably 70 ° to 330 ° C., more preferably 90 ° to 150 ° C.) Return to the reaction mixture gas stream. Optionally,
A portion of the separated product gas stream is mixed with air, ammonia and molecular nitrogen to provide a molecular oxygen content of 1.0 to 20.0% by volume, preferably 1.5 to 15.0% by volume, more preferably 2% by volume. 0.0-12.5% by volume. The ratio of ammonia to oxygen capacity concentration is 0.2 to 5.0, preferably 0.5 to 2.0, more preferably 0.8 to 1.5. The nitrous oxide may include nitrogen and is produced separately from the rest of the product gas stream.

In one embodiment, the method of the present invention can be performed as follows. First, a reaction mixture gas stream is formed in two stages. In the first stage, the dedusted air is mixed with a portion of the separated and recycled product gas stream. Then, in a second stage, ammonia is added. This purpose can also be achieved with aqueous ammonia (ammonia may be added at any stage). Nitrogen can be added in one stage to obtain a more diluted N ₂ O gas product. Diluted products also may also contain CO _2, or such as argon inert mixture. The oxygen content in the reaction mixture gas stream is controlled to 1.0 to 20 by controlling the air flow rate, product section, ammonia and nitrogen.
. 0% by volume, preferably 1.5 to 15.0% by volume, more preferably 2.0%
To 12.5% by volume, while the ratio of the volumetric concentrations of ammonia and oxygen molecules is between 0.2 and 5.0, preferably between 0.5 and 2.0, more preferably between 0.
8 to 1.5.

The reaction mixture gas stream is introduced into an oxidation catalyst bed. Oxidizes ammonia to nitrous oxide
The composition of the catalyst for MnO₂/ Bi₂O₃/ Al₂O₃Or MnO₂/ Bi ₂ O₃/ Fe₂O₃Or MnO₂Or MnO₂/ Bi₂O₃Or MnO₂ / CuO. The following reactions that oxidize ammonia to nitrous oxide on these catalysts
Serve to: 2NH₃+ 2O₂→ N₂+ 2H₂O (I) At the same time as reaction (I), an undesired reaction takes place in the catalyst bed: 2NH₃+ 5 / 2O₂→ 2NO + 3H₂O (II) 2NH₃+ 3 / 2O₂→ N₂+ 3H₂O (III) Reaction (II) produces nitrogen oxides (NOx), while reaction (III)
Final product (N₂The selectivity to O) is reduced. All of the above catalysts are sub-oxidized
Provides over 80% selectivity for nitrogen, which is
This is an important parameter. On the other hand, only 0.3 to 3.0% of ammonia
NOx is oxidized by the reaction (II). Part of NOx due to reaction on catalyst
Has been reduced.

4NO + 4NH ₃ + O ₂ → 4N ₂ + 6H ₂ O (IV) The oxidation of ammonia to nitrous oxide is carried out on a catalyst at 200 to 400 ° C. A great deal of heat is generated between reactions (I) and (III). Accordingly, the temperature of the reactor can be adjusted by removing heat. For example, when using a tubular reactor (with the catalyst in a tube) or using a multi-bed adiabatic reactor (with the catalyst incorporated into the bed), heat can be removed between the beds and the fluidized catalyst bed can be removed. If used, the heat exchanger is mounted inside the floor.

Upon passing through the catalyst bed, the reaction mixture gas stream mainly comprises molecular nitrogen, water vapor, nitrous oxide (N ₂ O), nitrogen oxides (NOx) and residual unreacted oxygen molecules and products containing ammonia. Convert to gas flow. Then a portion of the product gas stream (1 to 98% by volume, preferably 10 to 95% by volume, more preferably 25 to 89% by volume)
% By volume) at a temperature of 5 ° C. to 450 ° C., preferably 70 ° to 330 ° C. (more preferably 90 ° to 150 ° C.) and return to the reaction mixture gas stream.

Although the product gas stream can be condensed prior to recycling, the portion to be recycled is preferably recycled at a temperature above the moisture condensation temperature. This eliminates the need for a separate device used to condense and evaporate the recycle gas stream before feeding it to the reactor. In this case, the product gas stream is condensed after partly recycled to the reactor. If the product gas stream is condensed before recycling part to the reactor, any conventional means of evaporation, for example conventional heat exchange using heat obtained from the product gas stream before condensing The recycle portion can be evaporated by a device or other heat transfer means. The recycled portion includes N ₂ O, H ₂ O, NH ₃ , O ₂ , NOx, N _{2 and the} like.

The separated portion of the product gas stream can be continuously recycled to a two-stage reaction mixture. In the first stage, a separate portion of the product gas stream is continuously mixed with the feed air. In the second stage, ammonia is supplied to the resulting gas mixture (ammonia may be added in any stage). Nitrogen may be added at any stage and may contain an inert mixture. The molecular oxygen content remains within 1.0 to 20.0% by volume, preferably 1.5 to 15.0% by volume, more preferably 2.0 to 12.5% by volume, and the volume concentration of ammonia and molecular oxygen Ratio of 1.0 to 1.5
The reaction mixture gas stream can be prepared to be within the range

Part of the product gas stream (5 to 90% by volume of the total gas stream, preferably not more than 8
80% by volume, more preferably 11 to 75% by volume)
Obtain the final product, nitrogen, which is diluted with molecular nitrogen as inert gas
Good. However, to improve the composition of the final product, some of the product gas stream
At 150 to 500 ° C, preferably at 175 to 450 ° C, more preferably
Is a catalyst bed for selective NOx reduction with ammonia at 200-400 ° C
Let it through. For this purpose V₂O₅/ Al₂O₃, V₂O₅/ TiO₂Or Cr ₂ O₃And the like. In addition to reaction (IV),
Also produces nitrous oxide: 4NO + 4NH₃+ O₂→ 4N₂O + 6H₂O (V) In reactions (IV) and (V), nitrogen oxide (NOx), residual oxygen in the final product
And the ammonia content is reduced.

If the residual oxygen content in the final product needs to be further reduced, flammable gases (CO, H ₂ , hydrocarbons) are introduced into the rest of the product gas stream. These combustible gases react with molecular oxygen to produce only carbon dioxide (CO ₂ ) and / or water. The following reactions take place: CO + 1 / 2O ₂ → CO ₂ (VI) H ₂ + 1 / 2O ₂ → H ₂ (VI) C _X H _Y + nO ₂ → XCO ₂ + Y / 2H ₂ O (VII) for, to no 50 ° C. 500 ° C., preferably from 175 ° C. to 450 ° C., more preferably not 200 ° C. to metal oxidant product gas stream at a temperature of _{400 ℃ (MnO 2 / Al 2} O 3, CuO / Cr 2 O ₃ / Al ₂ O ₃ ) or a noble metal (Pt / Al ₂ O ₃ , Pd / Al ₂ O ₃ ) based sufficient oxidation catalyst bed. At the outlet of the catalyst bed, the ratio of N ₂ O / O ₂ is 10 or more, preferably 2
It is 0 or more, and more preferably 100 or more.

Ammonia and water can be removed from the product gas stream by known methods such as condensation and the final product is dried as nitrous oxide-diluted gas containing a small amount of the mixture containing nitrogen. obtain. If it is necessary to reduce the nitrous oxide concentration in the final product to a certain value, an inert gas such as molecular nitrogen or carbon dioxide can be introduced into the reaction mixture gas stream or the product gas stream.

Another embodiment of the present invention provides a reaction mixture comprising ammonia and an oxidant to a reactor; oxidizing the ammonia to form nitrous oxide and NOx; NO
A method for producing nitrous oxide, comprising forming a nitrous oxide product gas stream by reducing x to nitrous oxide.

The oxidation and reduction steps described above can be performed in one reactor or in separate reactors, including the separate zones or chambers of one reactor as defined herein. In addition, the oxidation and reduction steps can be carried out simultaneously or sequentially using one catalyst or different catalysts. For example, an oxidation catalyst described herein can be used, or a combination of an oxidation catalyst in one reactor and a reduction catalyst (described herein) in another reactor (as used herein). (Under the conditions described above). The reaction products from the reactor can be recycled as described herein above. Also, when using two reactors,
The product from each reactor can be recycled to the inlet of each reactor, or the reaction product from the last reactor can be recycled to the first reactor.

The oxidizing agent used in the reaction includes oxygen, NOx, air, ozone, HNO _3, or any oxidizing agent capable of oxidizing ammonia. Preferably, the oxidizing agent is oxygen.

The NOx present in the reaction product from the first reactor is greater than the NOx present in the reaction product from the last reactor. N present in the reaction product of the last reactor
The amount of Ox is less than 5% by volume of the volume of the reaction product gas stream, preferably less than 3% by volume;
More preferably less than 1% by volume Examples The method of the present invention is described in further detail by the following examples.

Example 1 A method for producing nitrous oxide is carried out as follows. Pre-dusted air is added at a flow rate of 7.32 l / min to a separate portion of the product gas stream supplied at a flow rate of 21.0 l / min. Ammonia is then added to the mixture gas stream at a flow rate of 1.24 g / min. The chemical reactor thus obtained was prepared with a fixed bed of manganese bismuth catalyst (MnO ₂ / Bi ₂ O ₃ / Al ₂ O ₃ ) with a mass of 60 g inside a metal tube with an inner diameter of 15 mm. The reaction mixture gas stream is fed continuously. The tube with the catalyst is mounted inside an air-fluidized sand bed and subjected to the removal of severe reaction cracks. Maintain the catalyst bed temperature at 300 ° C. Product gas stream present in the catalyst bed is molecular nitrogen, water, nitrogen oxides (NO and NO _2), containing residual unreacted ammonia and oxygen as well as nitrous oxide. Since no water condensation occurs at 90 ° C., a portion of the product gas stream is separated and recycled to the catalyst bed. The remaining portion of the product gas stream is withdrawn from the recycle loop and developed into the final product using known methods.

In a continuous reaction scheme, the reaction mixture gas stream at the feed flow rate at the reactor inlet has the following composition (% by volume): N ₂ -63.3; H ₂ O-19.9; NO-0 .05
_{; N 2 O-5.1; NH} 3 -6.5; O 2 -4.9. Non recycle portion of the product gas stream reached 30% of the total product gas stream has the following composition _{(volume%): N 2 -63.8; H} 2 O-27.3; NO-0.07 _{; N 2 O-7.3; NH} 3 -1
. _5; O 2 -0.05.

Example 2 The method is carried out as in Example 1. Bulk catalyst MnO ₂ / B weighing 1200 g
i ₂ O ₃ is used. The air feed rate is 1.4 liters / minute and a separate portion of the product gas stream is fed at a flow rate of 13.3 liters / minute. The feed rate of ammonia is 0.22 g / min. The temperature of the catalyst bed is 320 ° C. Separation of the product gas stream is carried out at 320 ° C.

In a continuous reaction scheme, the reaction mixture gas stream fed at the feed rate has the following composition (% by volume) at the reactor inlet: N ₂ -64.7; H ₂ O-24.7; NO −
_{0.15; N 2 O-6.47;} NH 3 -2.0; O 2 -2.0. The non-recycled portion of the product gas stream is 88.7% and has the following composition (% by volume): N ₂ −
_{64.8; H 2 O-27.5;} NO-0.17; N 2 O-7.29; NH 3 -0
. _1; O 2 -0.15.

Example 3 The method is carried out as in Example 1. A bulk catalyst MnO ₂ weighing 1550 g is used. The air feed rate is 9.3 liters / minute and a separate portion of the product gas stream is fed at a flow rate of 3.8 liters / minute. The feed rate of ammonia is 1.46 g /
Minutes. The temperature of the catalyst bed is 330 ° C. Separation of the product gas stream is performed at 330 ° C.

In a continuous reaction scheme, the reaction mixture gas stream fed at the feed rate has the following composition at the reactor inlet (% by volume): N ₂ -64.3; H ₂ O-8.7; NO −0
. _{04; N 2 O-1.68;} NH 3 -12.8; O 2 -12.5. Non recycle portion of the product gas stream is 75.0% has the following composition _{(volume%): N 2 -65.1; H} 2 O-27.4; NO-0.17; N 2 O -6.66; NH ₃ -
_0.25; O 2 -0.47.

Example 4 The method is carried out as in Example 1. 850 g bulk catalyst MnO ₂ / Cu
O is used. The air feed rate is 7.27 liters / minute and provides a separate portion of the product gas stream at a flow rate of 21.1 liters / minute. Ammonia feed rate is 1
. 30 g / min. The temperature of the catalyst bed is 310 ° C. Product gas stream separation of 7
Performed at 0 ° C.

In a continuous reaction scheme, the reaction mixture gas stream fed at the feed rate has the following composition at the reactor inlet (% by volume): N ₂ -63.2; H ₂ O-19.8; NO −
_{0.06; N 2 O-4.76;} NH 3 -7.3; O 2 -4.9. The non-recycled portion of the product gas stream is 30.0% and has the following composition (% by volume): N ₂ −
_{63.5; H 2 O-27.2;} NO-0.08; N 2 O-6.79; NH 3 -2
. _32; O 2 -0.15.

Example 5 The method is carried out as in Example 1. A catalyst MnO ₂ / Bi ₂ O ₃ / Fe ₂ O ₃ with a mass of 850 g is used. The air feed rate is 6.32 liters / minute, providing a separate portion of the product gas stream at a flow rate of 18.0 liters / minute. The feed rate of ammonia is 1.02 g / min. Pure nitrogen is added to the reaction mixture at a flow rate of 4.31 l / min. The temperature of the catalyst bed is 310 ° C. Product gas stream separation of 100
Performed at ° C.

In a continuous reaction scheme, the reaction mixture gas stream fed at the feed rate has the following composition (% by volume) at the inlet of the reactor: N ₂ -77.1; H ₂ O-11.3; NO −
_{0.06; N 2 O-2.67;} NH 3 -4.6; O 2 -4.3. The non-recycled portion of the product gas stream is 40.0% and has the following composition (% by volume): N ₂ −
_{77.3; H 2 O-17.8;} NO-0.11; N 2 O-4.44; NH 3 -0
. _30; O 2 -0.08. Example 6 The method is carried out as in example 1. A catalyst MnO ₂ / Bi ₂ O ₃ / Al ₂ O ₃ with a mass of 650 g is used. The air feed rate is 6.93 liters / minute, providing a separate portion of the product gas stream at a flow rate of 17.1 liters / minute. The feed rate of ammonia is 1.08 g / min. An inert gas containing 90% by volume of nitrogen and 10% by volume of CO ₂ is added to the reaction mixture gas stream at a flow rate of 4.51 l / min.
The temperature of the catalyst bed is 310 ° C. Separation of the product gas stream is carried out at 100 ° C.

In a continuous reaction scheme, the reaction mixture gas stream fed at the feed rate has the following composition at the reactor inlet (% by volume): N ₂ -73.4; H ₂ O-10.9; NO −
_{0.06; N 2 O-2.70;} NH 3 -4.8; O 2 -4.6; CO 2 -3.5
. The non-recycled portion of the product gas stream is 43.0% and has the following composition (
_{Volume%): N 2 -73.5; H} 2 O-17.1; NO-0.11; N 2 O-4.
_{74; NH 3 -0.16; O 2} -0.09; CO 2 -3.5.

Example 7 The method is carried out as in Example 1. A catalyst MnO ₂ / Bi ₂ O ₃ / Al ₂ O ₃ with a mass of 850 g is used. The air feed rate is 4.35 liters / minute and provides a separate portion of the product gas stream at a flow rate of 15.9 liters / minute. Ammonia is supplied as ammonia water whose ammonia content by evaporation is 20% by weight. The feed rate of ammonia is 3.89 g / min. The temperature of the catalyst bed is 300 ° C. Separation of the product gas stream is carried out at 100 ° C.

In a continuous reaction scheme, the reaction mixture gas stream fed at the feed rate has the following composition at the reactor inlet (% by volume): N ₂ -36.6; H ₂ O-52.0; NO −
_{0.06; N 2 O-2.68;} NH 3 -5.1; O 2 -3.5. The non-recycled portion of the product gas stream is 37.0% and has the following composition (% by volume): N ₂ −
_{36.7; H 2 O-57.2;} NO-0.09; N 2 O-4.25; NH 3 -1
. _58; O 2 -0.11.

Example 8 The method is carried out as in Example 2. The remaining portion of the product gas stream withdrawn for the end product is passed through a V ₂ O ₂ / TiO ₂ catalyst bed for reducing nitrogen oxides with ammonia. The temperature of the catalyst bed is 320 ° C. The residual NO content after passing through the catalyst bed is 0.005% by volume.

Example 9 The method is carried out as in Example 3. Hydrogen is added to the remainder of the product gas stream at a flow rate of 0.1 l / min and the mixture is passed through a Pt / Al ₂ O ₃ catalyst bed. The temperature of the catalyst bed is 330 ° C. The residual O ₂ content after passing through the Pt catalyst bed is 0.025% by volume.

Example 10 A method for producing nitrous oxide is carried out as follows. The flow rate of the composition and the reaction mixture continuously fed to the chemical reactor is the same as in Example 1. 200 g of F
insulation moieties and cooling the tubular portion comprises a fixed catalyst bed of e ₂ O ₃ basis (inner diameter 15mm
The process is carried out in a chemical reactor consisting of a fixed bed of 650 g of manganese bismuth catalyst (MnO ₂ / Bi ₂ O ₃ / Al ₂ O ₃ ) in a tube of 650 g.
The temperature of the reaction mixture at the inlet of the adiabatic part is 300 ° C and the temperature at the inlet of the tubular part is -280 ° C. Cool the reaction mixture between the adiabatic section and the tubular section. All other points are implemented as in the first embodiment. The composition at the outlet of the reactor and the composition of the recycled gas stream are the same as in Example 1.

Example 11 A method for producing nitrous oxide is carried out as follows. The flow rate of the composition and the reaction mixture continuously fed to the chemical reactor is the same as in Example 1. The chemical reaction device has an inner diameter of 20 mm and has a mass of 800 g of a manganese-bismuth catalyst (MnO ₂ /
Bi ₂ O ₃ / Al ₂ O ₃ ) made of metal tubing containing a fixed bed. The tube containing the catalyst was mounted on an air-fluidized sand bed to remove the intense heat of reaction and raise the temperature to 280.
Keep at ° C. The temperature of the reaction mixture at the inlet of the reactor is 350 ° C. All other details are implemented as in Example 1. The composition at the outlet of the reactor and the composition of the recycled gas stream are the same as in Example 1.

──────────────────────────────────────────────────続 き Continuation of front page (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE ), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SL, SZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AL, AM, AT, AU, AZ, BA, BB, BG, BR , BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS , JP, KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, UA, UG, UZ, VN, YU, ZA, ZW (72) Inventor Urrialte, Antony Kay United States of America, Florida 32514, Pensacola, Utdran Court, 9221 (72) Inventor Oppenheim, Judidispie United States, Florida 32501, Pensacola, Port Royal Way 13 (72) Inventor Avener, Jielie Earl United States of America, Missouri 63376, Cent Peters, Bentwood Lane 233 (72) Inventor Beakler, Chris Earl United States, Florida 32561, Penn Sakora Beach, Kar Hermosa 27 (72) Inventor Moklinsky, Vladimir Basili Vicci Russia, Novosibirsk 630058, Latskyan Street 13, Apartment 94 (72) Inventor Slavinskaya, Elena Marcobuna Russia Country, Novosibirsk 630058, Ek Battlenaya Street 14, Apartment 94 (72) Inventor Noskov, Alexander Stepanovicz Russia, Novosibirsk 630058, Tsvetnoy Road 9, Apartment 14 (72) Inventor Zorotalksky, Ilya Alexandrovitsy Novosibirsk, Russia 630058, Detzky Road, 9 Apartment, 2F F-term (reference) 4H006 AA02 AC41 AC42 AC44 AC46 BA06 BA09 BA12 BA25 BA29 BA30 BA55 BA60 BD33 BD52 BE02 BE20 BE90 BS10 DA12 FC22 FC52 FE12 FE13

Claims (25)

[Claims] 1. Hydroxylating an aromatic compound using nitrous oxide in a reactor to form a phenolic compound; reducing the phenolic compound to form a cycloaliphatic ketone or alcoholic compound. Oxidizing the cycloaliphatic ketone or alcoholic compound to form an aliphatic diacid compound and a nitrous oxide gas stream; reacting the nitrous oxide gas stream to provide a pure nitrous oxide gas stream; And recycling the pure nitrous oxide gas stream to the reactor. 2. The method of claim 1 wherein said reaction comprises the conversion of O ₂ to nitrous oxide and the reduction of NOx to N ₂ and nitrous oxide. 3. The method according to claim ₂ , wherein the conversion of O _{2 comprises} converting the O ₂ to nitrous oxide by ammonia oxidation. 4. The method of claim 2 wherein said reduction of NOx comprises oxidation of ammonia to produce nitrous oxide as a reaction product. 5. The method according to claim 1, wherein the pure nitrous oxide gas stream is mixed with further nitrous oxide. 6. The method of claim 5, wherein said further nitrous oxide is produced by ammonia oxidation. 7. The method according to claim 1, wherein the ammonia oxidation supplies a reaction mixture comprising ammonia, nitrous oxide and an oxidant to an ammonia oxidation reactor; and oxidizes ammonia to form a nitrous oxide product gas stream. Removing at least a portion of the nitrous oxide product gas stream to form a separated recycle gas stream; feeding the separated recycle stream to the ammonia oxidation reactor; and the nitrous oxide product; Purifying a gas stream to form the additional nitrous oxide;
The method of claim 6, comprising: 8. The method of claim 7, wherein the recycle gas stream comprises a portion of the nitrous oxide product gas stream, water, air, molecular oxygen, molecular nitrogen, nitrous oxide, NOx, or an inert gas. the method of. 9. The method of claim 7 wherein said recycle gas stream is removed from said nitrous oxide product gas stream at a temperature above the moisture condensation temperature. 10. The method of claim 7, wherein air, water, molecular nitrogen, molecular oxygen, nitrous oxide, ammonia or an inert gas is added to the recycle gas stream. 11. A NOx-containing gas stream comprising: supplying a reaction mixture comprising ammonia and said NOx-containing gas stream to a reactor; and reducing NOx to form a nitrous oxide product gas stream. A method for producing nitrous oxide by reacting 12. The method comprising: removing at least a portion of the nitrous oxide product gas stream to form a separated recycle gas stream; supplying the separated recycle gas stream to the reactor; The method of claim 11, comprising: and separating nitrous oxide from the nitrous oxide product gas stream. 13. The reaction mixture of claim 11, wherein the reaction mixture comprises a diluent comprising the nitrous oxide product gas stream, water, air, molecular oxygen, molecular nitrogen, nitrous oxide or an inert gas. the method of. 14. The method of claim 11, wherein air, water, molecular nitrogen, molecular oxygen, nitrous oxide, ammonia or an inert gas is added to the recycle gas stream. 15. Feeding a reaction mixture comprising ammonia and an oxidant to a reactor; oxidizing the ammonia to form a nitrous oxide product gas stream comprising nitrous oxide as a major component. Removing at least a portion of the nitrous oxide product gas stream at a temperature above the moisture condensation temperature to form a separated recycle gas stream; supplying the separated recycle gas stream to the reactor; Separating nitrous oxide from the nitrous oxide product gas stream; and producing nitrous oxide by ammonia oxidation. 16. The reaction mixture comprising a portion of the nitrous oxide product gas stream, a diluent comprising water, air, molecular oxygen, molecular nitrogen, nitrous oxide or an inert gas. 16. The method according to 15. 17. The method of claim 15, wherein air, water, molecular nitrogen, molecular oxygen, nitrous oxide, ammonia or an inert gas is added to the recycle gas stream. 18. The method of claim 15, oxide body comprises oxygen, NOx, air, ozone or HNO _3. 19. A reaction mixture comprising ammonia and an oxidant is provided to a reactor; oxidizing the ammonia to form nitrous oxide and NOx; reducing the NOx to nitrous oxide to form nitrous oxide. Forming a nitric oxide product gas stream. 20. The method of claim 19, wherein a portion of said nitrous oxide product gas stream is recycled to said reactor. 21. The oxidation in a first reactor to form a first nitrous oxide product gas stream, and the reduction in a second reactor to produce a second nitrous oxide product. 20. The method according to claim 19, wherein a flow of the product gas is formed. 22. The method according to claim 21, wherein said first and second reactors are filled with different catalysts. 23. The method of claim 21, wherein a portion of said second nitrous oxide product gas stream is recycled to said first or second reactor. 24. The method of claim 21 wherein the amount of nitrous oxide present in said second product gas stream is greater than the amount of nitrous oxide present in said first product gas stream. 25. The method of claim 19, oxide body comprises oxygen, NOx, air, ozone or HNO _3.