JP2010207688A - Method for preparing catalyst for manufacturing phenol, catalyst prepared by the preparing method and method for manufacturing phenol - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for preparing a catalyst for effectively manufacturing phenol from benzene and to provide a method for manufacturing phenol by using the catalyst. <P>SOLUTION: The method for preparing the catalyst by making rhenium and at least one of platinum and palladium carried on a metal oxide includes a process of obtaining the metal oxide carrying rhenium by impregnation with the metal oxide and a solution containing methyl trioxorhenium, and is designed to prepare the catalyst for manufacturing phenol by oxidizing benzene with oxygen. The method for manufacturing phenol by using the catalyst is also included. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for producing a catalyst for producing phenol by oxidizing benzene with oxygen, a catalyst obtained by the production method, and a method for producing phenol.

  As a method for industrially producing phenol using benzene as a raw material, a method (cumene method) in which phenol is obtained from benzene and propylene via cumene hydroxyperoxide is exclusively used. This method has a problem of supply and demand balance with co-produced acetone and a problem that is economically inefficient because it is a three-stage process. On the other hand, a method of oxidizing toluene to phenol (toluene method) has also been carried out, but it is no longer an economically advantageous method due to the rising price of toluene. Under such circumstances, there is a demand for a method in which phenol is obtained directly from benzene without any by-products.

  As a method of directly obtaining phenol from benzene, in addition to a method using molecular oxygen as an oxidizing agent, a method using an oxidizing agent other than molecular oxygen and a stoichiometric combination of an oxidizing agent and a reducing agent. The method is known.

As a method of using molecular oxygen as an oxidizing agent, a method using the following catalyst has been proposed.
(A) Pd (OAc) ₂ / heteropoly compound catalyst (100 ° C.); benzene conversion 6%, phenol selectivity 64% (for example, see Non-Patent Document 1).

(B) CuH / ZSM-5 catalyst (400 ° C.); phenol yield 0.8% (for example, see Patent Document 1).
(C) V ₄ Mo ₈ O _Z / SiO ₂ catalyst (550 ° C.); benzene conversion 33.5%, phenol selectivity 7.9% (for example, see Patent Document 2).

  However, in the direct oxidation with molecular oxygen, a benzene polymer such as biphenyl and a sequential oxide of phenol (catechol, pyrogallol, etc.) are by-produced. Therefore, a high phenol selectivity cannot be obtained unless the conditions are extremely low, and it has not been put to practical use.

  Non-Patent Document 2 reports that phenol can be produced with high selectivity by reacting benzene with oxygen in the presence of a catalyst composed of rhenium immobilized in zeolite pores and ammonia. This catalyst is obtained by chemical vapor deposition of H-ZSM-5 and methyltrioxorhenium, which is a sublimable complex, and then ammonia treatment. The reaction is performed by a gas phase contact method. After a predetermined amount of the catalyst is filled in a reaction tube, an activation treatment is performed at a predetermined temperature under a flow of an inert gas, and then a catalyst layer containing benzene and oxygen together with ammonia at a predetermined ratio. It is carried out by distributing it. However, in the production of the catalyst, a special method called a chemical vapor deposition method is required, and even the phenol production method using the catalyst has a low conversion rate of benzene, which is not sufficient.

  The present inventors further show that the benzene conversion rate can be further increased by combining a group 10 metal such as platinum with a catalyst composed of rhenium and a metal oxide such as H-ZSM-5. Already found (Japanese Patent Application No. 2008-98460). However, the catalyst performance has left room for improvement from the viewpoint of industrial phenol production.

  In addition, as a method using a special oxidizing agent, a method using expensive nitrous oxide or hydrogen peroxide has been reported (for example, see Non-Patent Documents 3 and 4). However, these special oxidizers require equimolar amounts relative to the phenol to be produced, and are not economically feasible as a phenol production method that is expected to be mass-produced as a general-purpose chemical product. Not in.

On the other hand, as a method for using a reducing agent in combination with a phenol production method, a method using H ₂ in combination (for example, see Patent Document 3) and a method using CO in combination (for example, see Patent Document 4) are known. . However, on sequential phenol selectivity is low for the reaction, problems H ₂ is consumed as a large amount of water, (danger of explosion due to a mixture of CO toxicity and O ₂ and H ₂₎ safety issues It has not yet been put to practical use.

JP 2000-212112 A JP 2000-327612 A JP 07-179383 A JP-A-62-292738

J. Mol. Catal. A: Chemical, 185, 285-290 (2002) Angew. Chem. Int. Ed., 45, 448-450 (2006) Applied Catal. A: General, 244, 11-17 (2003) Angew. Chem. Int. Ed., 42, 4937-4940 (2003)

  An object of the present invention is to provide a method for producing a catalyst for efficiently producing phenol from benzene, a catalyst obtained by the production method, and a method for producing phenol using the catalyst.

  As a result of earnest research to solve the above problems, the present inventor has found that when producing a catalyst in which rhenium and at least one selected from platinum and palladium are supported on a metal oxide, By having a step of obtaining a metal oxide carrying rhenium by impregnation using a solution containing trioxorhenium and a metal oxide, phenol is efficiently converted from benzene with high benzene conversion and high phenol selectivity. The inventors have found that a catalyst for production can be obtained, and have reached the present invention.

  That is, the method for producing a catalyst for producing phenol by oxidizing benzene with oxygen according to the present invention is a catalyst in which rhenium and at least one selected from platinum and palladium are supported on a metal oxide. In which a metal oxide carrying rhenium is obtained by impregnation using a solution containing methyltrioxorhenium and a metal oxide.

  Further, in the method for producing a catalyst for producing phenol by oxidizing benzene with oxygen according to the present invention, rhenium is supported by an impregnation treatment using a solution containing methyltrioxorhenium and a metal oxide. A step of obtaining a metal oxide is performed, and then a step of drying the metal oxide supporting rhenium is performed, and at least one selected from platinum and palladium is supported on the metal oxide supporting rhenium. It is preferable to perform a process.

  The method for producing a catalyst for producing phenol by oxidizing benzene with oxygen according to the present invention includes a step of supporting at least one selected from platinum and palladium on a metal oxide, It is preferable to perform a step of obtaining a metal oxide carrying rhenium by impregnation using a solution containing methyltrioxorhenium and a metal oxide.

It is preferable that at least one selected from platinum and palladium is platinum.
The catalyst of the present invention is a catalyst for producing phenol obtained by oxidizing benzene with oxygen obtained by the above production method.

  The method for producing phenol of the present invention is a method for oxidizing benzene with oxygen in the presence of the catalyst. The production method is preferably performed in the presence of ammonia.

  According to the present invention, phenol can be produced from benzene with high selectivity and high conversion.

  The method for producing a catalyst for producing phenol by oxidizing benzene with oxygen according to the present invention produces a catalyst in which rhenium and at least one selected from platinum and palladium are supported on a metal oxide. The method comprises a step of obtaining a rhenium-supported metal oxide by impregnation using a solution containing methyltrioxorhenium and a metal oxide.

The following two aspects are mentioned as a preferable aspect of the manufacturing method of the catalyst for manufacturing a phenol by oxidizing the benzene of this invention with oxygen.
As a method for producing a catalyst for producing phenol by oxidizing benzene with oxygen in the first preferred embodiment, rhenium is supported by an impregnation treatment using a solution containing methyltrioxorhenium and a metal oxide. A step of obtaining a metal oxide, followed by a step of drying the metal oxide supporting rhenium, and supporting at least one selected from platinum and palladium on the metal oxide supporting rhenium It is characterized by performing the process to do.

  The method for producing a catalyst for producing phenol by oxidizing benzene with oxygen according to the second preferred embodiment includes a step of supporting at least one selected from platinum and palladium on a metal oxide, And a step of obtaining a metal oxide carrying rhenium by an impregnation treatment using a solution containing methyltrioxorhenium and a metal oxide.

When at least one selected from platinum and palladium supported on the metal oxide is platinum, the activity of the catalyst obtained by complexing with rhenium tends to increase.
Conventionally, as a supporting method using methyltrioxorhenium, a chemical vapor deposition method (CVD method) has been frequently used taking advantage of the high sublimation property of methyltrioxorhenium.

  The method for producing a catalyst of the present invention includes a step of obtaining a metal oxide on which rhenium is supported by an impregnation treatment using a solution containing methyltrioxorhenium and a metal oxide. This step is also referred to as step (A). In this step, rhenium is supported on the metal oxide by the impregnation treatment using a solution containing methyltrioxorhenium and a metal oxide obtained by dissolving methyltrioxorhenium in a solvent. The obtained metal oxide is obtained.

  Examples of the solvent for dissolving methyltrioxorhenium include alcohols such as methanol, ethanol and propanol, and ethers such as ethyl ether, and are not limited as long as they can dissolve methyltrioxorhenium. Among these, when ethanol is used as a solvent, rhenium can be supported on the metal oxide in a highly dispersed state, so that a highly active catalyst tends to be obtained.

  A solution containing methyltrioxorhenium and a method for impregnation using a metal oxide can be used as long as the solution containing methyltrioxorhenium can be immersed in the metal oxide. The method may be performed by adding a metal oxide to the metal oxide, or by adding a solution containing methyltrioxorhenium to the metal oxide.

  As a specific method of the impregnation treatment using a solution containing methyltrioxorhenium and a metal oxide, a conventionally known impregnation method can be used, a pore filling method, an incipient wetness method, Examples thereof include an equilibrium adsorption method, an evaporation to dryness method, and a spray drying method. Among these, the impregnation method by the evaporation to dryness method is preferable in that the whole amount of rhenium to be used can be supported and the operation is simple.

  The metal oxide is preferably an aluminosilicate known as a catalyst carrier, more preferably zeolite. Specific examples of the zeolite include X-type, Y-type, L-type, mordenite, ferrierite, beta-type, ZSM-5 and the like. Of these, ZSM-5 is preferred.

The silica / alumina ratio (SiO ₂ / Al ₂ O ₃ molar ratio) of the zeolite is not particularly limited, but is preferably 1 to 200, more preferably 1 to 100, and more preferably 1 to 50. Is particularly preferred.

The cation species of the zeolite is not particularly limited, but suitable results can be obtained when ammonium (NH ₄ ⁺ ) type or proton (H ⁺ ) type zeolite is used as a raw material for catalyst production.

  The amount of rhenium supported on the metal oxide is not particularly limited, but is preferably 0.001 to 20 wt%, more preferably 0.01 to 10 wt% with respect to 100 wt% of the metal oxide. preferable.

  The amount of at least one selected from platinum and palladium supported on the metal oxide is preferably 0.001 to 20 wt% with respect to 100 wt% of the metal oxide, and 0.01 to 10 wt%. More preferably it is.

  The shape of the metal oxide is not particularly limited, and may be any of a spherical shape, a cylindrical shape, a ring shape, a porous column shape, an extruded shape, and a crushed shape, and the size of the particles is in the range of 0.01 mm to 100 mm. Select according to the size.

  As a method for producing a catalyst for producing phenol by oxidizing the benzene of the first preferred embodiment with oxygen, the metal oxide carrying rhenium is subsequently produced after performing the step (A). The process of drying is performed. This step is also referred to as step (B). In step (B), the rhenium-supported metal oxide is dried, and the solvent in which methyltrioxorhenium is dissolved is removed by evaporation.

  The drying temperature may be any temperature lower than the decomposition temperature (approximately 300 ° C.) of methyltrioxorhenium, preferably 150 ° C. or less, more preferably 100 ° C. or less, and further preferably 80 ° C. or less. In addition, the drying step is usually performed in air and at normal pressure. However, as long as the solvent can be evaporated without decomposing or sublimating methyltrioxorhenium, helium, nitrogen, etc. You may carry out in inert gas or under reduced pressure.

  As the method for producing a catalyst for producing phenol by oxidizing the benzene of the first preferred embodiment with oxygen, after performing step (B), at least one selected from platinum and palladium is used. Is carried out on the metal oxide on which is supported. This step is also referred to as step (C). By the step (C), a metal oxide carrying rhenium and at least one selected from platinum and palladium can be obtained.

  As a method of supporting at least one selected from platinum and palladium on a metal oxide on which rhenium is supported, any conventionally known method can be used, such as pore filling method, incident wetness (incipient wetness) ) Method, equilibrium adsorption method, evaporation to dryness method, spray drying method, etc., physical mixing method, precipitation method, kneading method, deposition method, ion exchange method, chemical vapor deposition method, etc. . Among these, the impregnation method and the ion exchange method by the evaporation to dryness method are suitable because they are easy to operate and uniform metal dispersibility is obtained.

The platinum source and palladium source used when supporting at least one selected from platinum and palladium on a metal oxide supporting rhenium are as follows.
The platinum source may be platinum alone or a platinum compound.

  The platinum compound is not particularly limited as long as the object of the present invention is not inhibited. For example, platinum chloride, chloroplatinic acid, chloroplatinic acid hydrate, platinum bromide, platinum oxide, platinum acetylacetonate, diammine platinum Nitrate, dinitrodiammine platinum, diammine platinum dichloride, diammine tetrachloroplatinum, tetraamminedichloroplatinum, dichlorotetraammineplatinum, tetraammineplatinum dichloride, tetraammineplatinum nitrate, tetraammineplatinum hydroxide, tetraammineplatinic acid tetrachloroplatinum, tetrachloroplatinic acid, tetrachloro Ammonium platinate, potassium tetrachloroplatinate, hexahydroxoplatinic acid, hexachloroplatinic acid, ammonium hexachloroplatinate, sodium hexachloroplatinate, potassium hexachloroplatinate, hexabromo Mention may be made of gold acid, and the like.

The palladium source may be palladium alone or a palladium compound.
The palladium compound is not particularly limited as long as the object of the present invention is not impaired, and examples thereof include palladium chloride, palladium nitrate, palladium sulfate, palladium acetate, palladium oxide, palladium hydroxide, dinitrodiammine palladium, diammine palladium nitrate, diammine. Dichloropalladium, tetraamminepalladium dichloride, tetraamminepalladium nitrate, tetraamminepalladium acetate, tetraamminepalladium dibromide, ammonium tetrachloropalladium, sodium tetrachloropalladate, potassium tetrachloropalladate, ammonium hexachloropalladium, potassium hexachloropalladate, palladium acetylacetate Such as nate, palladium hydride, palladium oxide, etc. .

  As a method for producing a catalyst for producing phenol by oxidizing benzene with oxygen according to the second preferred embodiment, a step of supporting at least one selected from platinum and palladium on a metal oxide is performed. This step is also referred to as a step (C ′). Step (C ′) can be performed in the same manner as in step (C) except that the metal oxide supporting rhenium in step (C) is replaced with a metal oxide.

  As a method for producing a catalyst for producing phenol by oxidizing benzene with oxygen according to the second preferred embodiment, step (C ') is carried out, followed by the step (A). In the method for producing a catalyst for producing phenol by oxidizing benzene with oxygen according to the second preferred embodiment, the step (A) is a platinum obtained by the step (C ′) as a metal oxide. And a metal oxide on which at least one selected from palladium is supported.

  Therefore, the rhenium-supported metal oxide obtained in step (A) in the method for producing a catalyst for producing phenol by oxidizing benzene with oxygen according to the second preferred embodiment comprises rhenium, platinum and At least one selected from palladium is supported on the metal oxide.

  In the method for producing a catalyst for producing phenol by oxidizing benzene with oxygen according to the second preferred embodiment, it is selected from platinum and palladium between step (C ′) and step (A). The metal oxide supporting at least one kind may be dried or fired. Conditions for drying or firing the metal oxide supporting at least one selected from platinum and palladium are not particularly limited.

  In the method for producing a catalyst for producing phenol by oxidizing benzene with oxygen according to the second preferred embodiment, at least one selected from rhenium, platinum and palladium is provided after step (A). The supported metal oxide may be dried by a known method. It is important that the drying temperature does not decompose or sublime the methyltrioxorhenium. As in the above step (B), for example, in the air and under normal pressure, it is preferably 150 ° C. or lower, and 100 ° C. The following is more preferable, and 80 ° C. or lower is further preferable.

  The catalyst of the present invention is a catalyst for producing phenol by oxidizing benzene with oxygen, and is a catalyst obtained by a method for producing a catalyst for producing phenol by oxidizing benzene with oxygen. When the catalyst of the present invention is used, phenol can be efficiently produced from benzene with high benzene conversion and high phenol selectivity.

  In the method for producing phenol of the present invention, benzene is oxidized with oxygen in the presence of the catalyst. By this method, phenol can be efficiently produced from benzene at a higher benzene conversion rate and higher phenol selectivity than before.

  In the method for producing phenol of the present invention, the catalyst is preferably used after pretreatment. Specific examples of the pretreatment include a method of treating the catalyst in an oxygen atmosphere at a temperature of 300 to 500 ° C. for 0.5 to 2 hours, and the catalyst in an oxygen atmosphere at a temperature of 300 to 500 ° C. Examples of the method include a treatment for 0.5 to 2 hours and a subsequent treatment in an ammonia atmosphere at a temperature of 200 to 500 ° C. for 0.5 to 2 hours. Among these, a method in which the catalyst is treated at a temperature of 300 to 500 ° C. in an oxygen atmosphere for 0.5 to 2 hours and then treated at a temperature of 200 to 500 ° C. in an ammonia atmosphere for 0.5 to 2 hours is preferable. Used for. In the treatment under an ammonia atmosphere, pure ammonia may be used, or ammonia diluted with an inert gas may be used. The treatment temperature in an ammonia atmosphere is more preferably 250 to 350 ° C, particularly preferably 260 to 300 ° C.

  The method for producing phenol of the present invention is carried out by an oxidation reaction in which oxygen is directly added to benzene in the presence of the catalyst. The oxidation reaction is preferably performed by a gas phase contact method. Moreover, although there is no restriction | limiting in particular as oxygen, It is preferable that it is molecular oxygen. The reactor is not particularly limited, and can be implemented in a fixed bed or a fluidized bed.

  The reaction temperature of the oxidation reaction is 50 to 700 ° C, preferably 100 to 600 ° C. The reaction pressure of the oxidation reaction is 0.01 to 100 MPa, preferably 0.05 to 10 MPa.

  The ratio of the catalyst used in the oxidation reaction is not particularly limited. For example, when the reaction is carried out by a fixed bed flow apparatus, a value obtained by dividing the supply amount of benzene per hour (volume as a gas) by the weight of the catalyst, In terms of GHSV, it is preferably 0.01 to 500,000 ml-benzene / g-cat / h, more preferably 0.1 to 300,000 ml-benzene / g-cat / h.

The ratio of oxygen used in the oxidation reaction is 0.01 to 50 mol, preferably 0.1 to 10 mol, per mol of benzene.
It is preferable to perform the manufacturing method of the phenol of this invention in presence of ammonia. In this case, the usage ratio of ammonia is 0.001 to 200 mol, preferably 0.01 to 100 mol, per mol of benzene.

  In the oxidation reaction, a reaction gas composed of benzene, oxygen and ammonia may be used as it is as a mixed gas, or may be further diluted with an inert gas such as nitrogen, helium or argon gas.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these Examples.

[Example 1]
Using an ethanol solution (0.20 mol / L) of NH ₄ -ZSM-5 (3.0 g, SiO ₂ / Al ₂ O ₃ = 30) and methyltrioxorhenium (CH ₃ ReO ₃ ) (0.201 g) The impregnation treatment was performed, and the obtained solid was dried at 80 ° C. for 6 hours. Impregnation treatment was performed using the solid obtained by drying and an aqueous solution (0.77 mol / L) of [NH ₃ ] ₄ Pt (NO ₃ ) ₂ (0.119 g), and the obtained solid was treated at 80 ° C. for 6 hours. The catalyst was dried to obtain catalyst A (5 wt% Re-2 wt% Pt) containing rhenium and platinum.

Catalyst A (1.0 g) was charged into the reactor, and under an oxygen flow at 500 ° C. for 2 hours, followed by a NH ₃ / He mixed gas (NH ₃ = 25%) flow at 280 ° C. for 2 hours. Processed.
A mixed gas of benzene / oxygen / ammonia = 1.0 / 2.0 / 5.5 (molar ratio) was passed as GHSV = 72 ml-benzene / g-cat / h, and the reaction was performed at 0.1 MPa and 260 ° C. It was. The reaction gas was sampled and analyzed by gas chromatography. Phenol was produced at a benzene conversion of 38% and a selectivity of 96%.

[Comparative Example 1]
It was obtained by impregnation using an aqueous solution (0.28 mol / L) of NH ₄ —ZSM-5 (3.0 g, SiO ₂ / Al ₂ O ₃ = 30) and NH ₄ ReO ₄ (0.216 g). The solid was dried at 80 ° C. for 6 hours. Impregnation treatment was performed using the solid obtained by drying and an aqueous solution (0.77 mol / L) of [NH ₃ ] ₄ Pt (NO ₃ ) ₂ (0.119 g), and the obtained solid was treated at 80 ° C. for 6 hours. Drying gave catalyst a (5 wt% Re-2 wt% Pt) containing rhenium and platinum.
The reaction was performed in the same manner as in Example 1 except that the catalyst a was used instead of the catalyst A. Phenol was produced at a benzene conversion of 2% and a selectivity of 79%.

[Example 2]
NH ₄ except for using H-ZSM-5 in place of _{-ZSM-5 (SiO 2 / Al} 2 O 3 = 30) in the same manner as in Example 1, catalyst B (5 wt% of rhenium and platinum Re- 2 wt% Pt) was obtained.
The reaction was performed in the same manner as in Example 1 except that the catalyst B was used instead of the catalyst A. Phenol was produced at a benzene conversion of 34% and a selectivity of 93%.

[Example 3]
Using an ethanol solution (0.20 mol / L) of NH ₄ -ZSM-5 (3.0 g, SiO ₂ / Al ₂ O ₃ = 30) and methyltrioxorhenium (CH ₃ ReO ₃ ) (0.201 g) The impregnation treatment was performed, and the obtained solid was dried at 80 ° C. for 6 hours. The solid obtained by drying was added to an aqueous solution (0.077 mol / L) containing [NH ₃ ] ₄ Pt (NO ₃ ) ₂ (0.149 g) and stirred at 80 ° C. for 12 hours for ion exchange. Filtration and washing. Then, it dried at 80 degreeC for 6 hours, and obtained the catalyst C (5 wt% Re-2.5 wt% Pt) containing rhenium and platinum.
The reaction was performed in the same manner as in Example 1 except that the catalyst C was used instead of the catalyst A. Phenol was produced at a benzene conversion of 18% and a selectivity of 77%.

[Example 4]
NH ₄ —ZSM-5 (3.0 g, SiO ₂ / Al ₂ O ₃ = 30) was added to an aqueous solution (0.077 mol / L) containing [NH ₃ ] ₄ Pt (NO ₃ ) ₂ (0.119 g). In addition, the mixture was stirred at 80 ° C. for 12 hours for ion exchange. Then, it filtered, washed with water, and dried at 80 degreeC for 6 hours. The solid obtained by drying and impregnation treatment using an ethanol solution (0.20 mol / L) of methyltrioxorhenium (CH ₃ ReO ₃ ) (0.201 g) were performed, and the obtained solid was treated at 80 ° C. for 6 hours. The catalyst D (5 wt% Re-2 wt% Pt) containing rhenium and platinum was obtained by drying.

Catalyst D (1.0 g) was charged into the reactor, and under an oxygen flow at 500 ° C. for 2 hours, followed by a NH ₃ / He mixed gas (NH ₃ = 25%) flow at 280 ° C. for 2 hours, before Processed.
A mixed gas of benzene / oxygen / ammonia = 1.0 / 2.0 / 5.5 (molar ratio) was passed as GHSV = 72 ml-benzene / g-cat / h, and the reaction was performed at 0.1 MPa and 260 ° C. It was. The reaction gas was sampled and analyzed by gas chromatography. Phenol was produced at a benzene conversion of 26% and a selectivity of 94%.

[Examples 5 to 9]
Except for changing the amount of rhenium and platinum to be supported by changing the amount of aqueous solution containing [NH ₃ ] ₄ Pt (NO ₃ ) ₂ and the ethanol solution of methyltrioxorhenium (CH ₃ ReO ₃ ). In the same manner as in Example 4, the catalysts E, F, G, H and J shown in Table 1 were obtained. The reaction was performed in the same manner as in Example 1 using these catalysts. The results are shown in Table 1.

［実施例１０〜１２］
ＮＨ₃／Ｈｅ混合ガス（ＮＨ₃＝２５％）を流通させる温度を、表２に示す温度に変えた以外は、実施例４と同様にして反応を行った。結果を合わせて表２に示した。

[Examples 10 to 12]
The reaction was carried out in the same manner as in Example 4 except that the temperature at which the NH ₃ / He mixed gas (NH ₃ = 25%) was circulated was changed to the temperature shown in Table 2. The results are shown in Table 2.

［実施例１３］
ＮＨ₃／Ｈｅ混合ガスのＮＨ₃濃度を、２５％から５０％に変えた以外は実施例４と同様にして反応を行った。ベンゼン転化率２０％、選択率９４％でフェノールが生成していた。

[Example 13]
The reaction was performed in the same manner as in Example 4 except that the NH ₃ concentration of the NH ₃ / He mixed gas was changed from 25% to 50%. Phenol was produced at a benzene conversion of 20% and a selectivity of 94%.

[Example 14]
The reaction was performed in the same manner as in Example 4 except that the pretreatment time with the NH ₃ / He mixed gas was changed from 2 hours to 1 hour. Phenol was produced at a benzene conversion of 20% and a selectivity of 93%.

[Example 15]
The reaction was performed in the same manner as in Example 4 except that the pretreatment with the NH ₃ / He mixed gas was not performed. Phenol was produced at a benzene conversion of 28% and a selectivity of 95%.

[Example 16]
Except for using [NH ₃ ] ₄ Pd (NO ₃ ) ₂ instead of [NH ₃ ] ₄ Pt (NO ₃ ) ₂ , a catalyst K (5 wt% Re− containing rhenium and palladium) was used in the same manner as in Example 1. 2 wt% Pd) was obtained.
The reaction was conducted in the same manner as in Example 1 except that the catalyst K (1.0 g) was used instead of the catalyst A. Phenol was produced at a benzene conversion of 13% and a selectivity of 85%.

Claims (7)

A method for producing a catalyst comprising rhenium and at least one selected from platinum and palladium supported on a metal oxide,
Phenol is produced by oxidizing benzene with oxygen, comprising a step of obtaining a metal oxide on which rhenium is supported by impregnation using a solution containing methyltrioxorhenium and a metal oxide For producing a catalyst for the purpose.   A step of obtaining a metal oxide carrying rhenium by an impregnation treatment using a solution containing methyltrioxorhenium and a metal oxide is performed, followed by a step of drying the metal oxide carrying rhenium. 2. The phenol is produced by oxidizing benzene with oxygen according to claim 1, wherein a step of supporting at least one selected from platinum and palladium on a metal oxide supporting rhenium is performed. The manufacturing method of the catalyst for doing.   The step of supporting at least one selected from platinum and palladium on a metal oxide, followed by a solution containing methyltrioxorhenium and an impregnation treatment using the metal oxide, thereby oxidizing the metal supported on rhenium. The method for producing a catalyst for producing phenol by oxidizing benzene with oxygen according to claim 1, wherein a step of obtaining a product is performed.   The production of a catalyst for producing phenol by oxidizing benzene with oxygen according to any one of claims 1 to 3, wherein at least one selected from platinum and palladium is platinum. Method.   The catalyst obtained with the manufacturing method of the catalyst for manufacturing a phenol by oxidizing benzene with oxygen as described in any one of Claims 1-4.   A process for producing phenol, wherein benzene is oxidized with oxygen in the presence of the catalyst according to claim 5.   The method for producing phenol according to claim 6, which is performed in the presence of ammonia.