JP2000327612A - Production of phenolic compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a phenolic compound in high selectivity in a single step reaction by direct gas phase oxidation of an aromatic hydrocarbon with molecular oxygen in the presence of steam using a specific catalytic composition. SOLUTION: This phenolic compound is obtained by direct gas phase oxidation of an aromatic hydrocarbon (pref. benzene) with molecular oxygen pref. at 400-700 deg.C in the presence of steam using a catalytic composition of the formula (VxMo12-xCyOz)100-a(SiO2) (V is vanadium; Mo is molybdenum; C is phosphorus, antimony, bismuth, tellurium, chromium, tungsten, manganese, iron, cobalt, nickel, copper, zinc, magnesium, lanthanum, cerium, boron, aluminum or the like; Si is silicon; O is oxygen; x is 1-12; y is 0-2; z is a number determined depending on the respective valences of the other elements; (a) is 0.1-99.9 wt.%).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing phenols, and more particularly, to a method for producing phenols in a single step by directly oxidizing an aromatic hydrocarbon under high temperature gas phase with molecular oxygen. It is about.

[0002]

2. Description of the Related Art Heretofore, there have been known several methods for directly producing phenols from aromatic hydrocarbons, in particular, a method for producing phenol from benzene and molecular oxygen in the presence of a catalyst in a high-temperature gas phase.

For example, JP-A-48-61439 discloses a method using copper phosphate and iron oxide, manganese oxide, cobalt oxide, or nickel oxide as a catalyst.
No. 271 discloses a method using a copper borate catalyst.
JP-A-1-16333 discloses a method using a catalyst in which tellurium oxide is supported on silica, and JP-A-6-116187 discloses a method using a heteropolyacid catalyst at a reaction temperature of 400 ° C. or lower. . However, these methods have problems such as a low reaction yield and a tendency for decomposition or volatilization of the catalyst components to occur.

[0004]

DISCLOSURE OF THE INVENTION The present inventors have studied diligently to develop a method for directly oxidizing aromatic hydrocarbons with molecular oxygen to produce phenols with high selectivity by one-step reaction. As a result, they have found that this object can be achieved by oxidizing aromatic hydrocarbons with molecular oxygen under specific conditions and in the presence of a specific catalyst, and completed the present invention.

[0005]

That is, the present invention relates to a method for synthesizing phenols by directly oxidizing aromatic hydrocarbons with molecular oxygen in the gas phase, comprising the steps of preparing a compound represented by the general formula (VxMo12-xCyOz) 100 in the presence of water vapor. -A (SiO2)
a (where V is vanadium, Mo is molybdenum, C is phosphorus,
Antimony, bismuth, tellurium, chromium, tungsten, manganese, iron, cobalt, nickel, copper, zinc, magnesium, lanthanum, cerium, boron, aluminum, niobium, tantalum, titanium, zirconium, sodium, potassium, rubidium and cesium Si represents silicon, and O represents oxygen. The subscripts x, y, and z each represent an atomic ratio,
x is 1 to 12, y is 0 to 2, and z is a value determined according to the valence of another element. a represents% by weight, and 0.1 to 9
9.9. The present invention relates to a process for producing phenols, characterized by using the catalyst composition represented by the formula (1).

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The aromatic hydrocarbon which can be used as a raw material in the production method of the present invention is benzene, naphthalene or an alkyl- or dialkyl-substituted thereof having 1 to 6 carbon atoms, preferably benzene or toluene. And more preferably benzene.

The phenols obtained by the production method of the present invention are hydroxy compounds in which one or two hydroxyl groups have been substituted for nuclei in the above aromatic hydrocarbons, or aromatic ketones and quinones in which the hydroxy compounds are further dehydrogenated. Yes, specifically, phenol, hydroquinone, benzoquinone, catechol, resorcin, cresol, naphthol, naphthoquinone, etc. are exemplified, but phenol is preferably the most important industrially.

According to the production method of the present invention, a high catalytic activity for phenols can be obtained by supporting a vanadium component on a silica carrier, but a higher activity can be obtained by supporting a molybdenum component on this. Can be. Molybdenum has a wide range of effects, but its activity is significantly reduced when vanadium is not included. Further, silica is very effective as a catalyst carrier, and without silica, the synthesis activity of phenols is significantly reduced.

As the raw material of the vanadium component of the catalyst composition used in the present invention, vanadium pentoxide, ammonium metavanadate, vanadyl oxalate, vanadyl sulfate and the like are used.

As a raw material for the molybdenum component, molybdate such as molybdenum trioxide, molybdic acid, ammonium paramolybdate, phosphomolybdic acid and salts thereof are used.

As the raw material of the component C, there are used respective acids and their salts, oxides, nitrates, hydrochlorides, sulfates and the like. The addition of the C component suppresses the production of carbon dioxide and carbon monoxide, and is effective in improving the selectivity.

As a raw material of silicon, silica sol, silica hydrogel, fumed silica, alkoxide of silicic acid, commercially available silica and the like are used.

The catalyst component is preferably used by being supported on a carrier such as silica, silica alumina, alumina, diatomaceous earth, titania and zirconia. In particular, when silica is used as a carrier, silica is also the most preferred carrier because it also serves as a catalyst component material and improves the selectivity of phenols.

The carrier may be used in the form of granules, tablets or the like, or the sol may be mixed with a catalyst component and then molded.

As a method for producing a catalyst using the above-mentioned raw materials, a general method can be used. For example, Catalyst Course (5) Catalyst Design (Catalysis Society of Japan) (1985) p.
Impregnation method (adsorption method, pore filling method, incipient wetness method, evaporation to dryness method, spray method), precipitation method (coprecipitation method, deposition method, kneading method), ion exchange method, hydrothermal synthesis described in 56 Method, a gas phase synthesis method, and a solid phase reaction method can be used.

The method for producing phenol by reacting an aromatic hydrocarbon with molecular oxygen using these catalysts can be carried out by any of a fixed bed, a fluidized bed and a moving bed.

The ratio of the aromatic hydrocarbon and oxygen supplied to the reaction system in the production method of the present invention is in the range of 1: 0.1 to 5, preferably 1: 0.5 to 4. As the oxygen gas, pure oxygen, an oxygen-containing gas diluted with an inert gas, or air can be used.

The ratio between the aromatic hydrocarbon and steam supplied to the reaction system is 1: 0.1 to 20. Preferably 1:
It is in the range of 0.5 to 15. In the present invention, by performing the reaction between the aromatic hydrocarbon and oxygen in the coexistence of steam, the production rate of carbon dioxide and carbon monoxide is suppressed, and the production rate of phenols is increased.

In the production method of the present invention, the reaction temperature is 400 to
700 ° C, preferably in the range of 430-650 ° C. The contact time between the raw material gas and the catalyst is usually 0.01 to 10
Seconds, preferably in the range of 0.02 to 5 seconds. The reaction can be performed under reduced pressure, atmospheric pressure, or increased pressure, but it is usually preferable to perform the reaction at a pressure near atmospheric pressure.

[0020]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but terms used in Examples and Comparative Examples are defined as follows.

[0021]

(Equation 1)

Example 1 A catalyst which was 5% supported V2O5 / SiO2 was prepared as follows. After dissolving 1014.3 mg of ammonium metavanadate in 150 ml of ion-exchanged water, 1.5 g of silica (Catalyst Society of Japan reference catalyst JRC-SIO-8) was immersed and evaporated to dryness. This catalyst precursor is dissolved in air in 10
It was dried at 0 ° C. for 5 hours and then calcined at 600 ° C. for 5 hours.
0.2 g of this catalyst was placed in a quartz tube having an inner diameter of 8 mm with quartz sand of 2.5 mm.
g, diluted and filled, and benzene / oxygen / steam = 5.6 /
Flow was performed at a partial pressure of 11.3 / 75.6 at a flow rate of 63 ml / min. Benzene conversion was 17.5%, phenol selectivity, hydroquinone selectivity, and benzoquinone selectivity were 13.9%, 3.5%, and 7.2%, respectively.

Example 2 A catalyst which was 5% supported V10Mo2O31 / SiO2 was prepared as follows. A catalyst was produced in the same manner as in Example 1, except that 77.1 mg of ammonium metavanadate and then 23.3 mg of ammonium paramolybdate were dissolved in 150 ml of ion-exchanged water. The reaction results are shown in Table 1.

Example 3 A catalyst which was 5% supported on V8Mo4O28 / SiO2 was prepared as follows. A catalyst was produced in the same manner as in Example 1, except that 56.6 mg of ammonium metavanadate and then 42.7 mg of ammonium paramolybdate were dissolved in 150 ml of ion-exchanged water. The reaction results are shown in Table 1.

Example 4 The procedure of Example 3 was repeated except that 44.0 mg of vanadium oxide was used instead of ammonium metavanadate and 34.9 mg of molybdenum oxide was used instead of ammonium paramolybdate, and the mixture was wet-pulverized and mixed with silica using a grinder. A catalyst was produced in the same manner as in Example 3. The reaction results are shown in Table 1.

Examples 5 to 7 Catalysts having the compositions shown in the columns of Examples 5 to 7 in Table 1 were produced and reacted in the same manner as in Example 1. The results are also shown in Table 1.

Example 8 A catalyst was produced by the same composition as in Example 7 except that the loading was changed to 10%, and by the same preparation method as in Example 1.
The reaction results are shown in Table 1.

Examples 9 to 11 Catalysts having the compositions shown in the columns of Examples 9 to 11 in Table 1 were produced and reacted in the same manner as in Example 1. However, primary ammonium phosphate was used as a raw material of phosphorus, and aluminum nitrate was used as a raw material of aluminum. The results are shown in Table 1.

Comparative Example 1 A catalyst which was 5% supported MoO3 / SiO2 was prepared as follows. A catalyst was produced in the same manner as in Example 1, except that 96.8 mg of ammonium paramolybdate was dissolved in 150 ml of ion-exchanged water. The reaction results are shown in Table 1.

Comparative Example 2 A catalyst which was 5% supported H3PMo12O40 / SiO2 was prepared as follows. A catalyst was produced in the same manner as in Example 1, except that 102.2 mg of H3PMo12O40.30H2O was dissolved in 150 ml of ion-exchanged water. The reaction results are shown in Table 1.

Comparative Example 3 A catalyst was produced in the same manner as in Example 3 in both composition and preparation method except that silica was not used. Table of reaction results
1 is shown.

Comparative Example 4 An activity test was conducted using the same catalyst as in Example 3 under the same reaction conditions except that steam was not flowed during the reaction. The reaction results are shown in Table 1.

Comparative Example 5 Heteropolyacid H3P having the same P / Mo / V ratio as in Example 8
V4Mo8O38.nH2O is ion exchanged water 150ml
And a catalyst was produced in the same manner as in Example 3. The reaction results are shown in Table 1.

[0034]

[Table 1]

[0035]

According to the present invention, it has become possible to produce phenols with high selectivity by one-step reaction by directly vapor-phase oxidizing aromatic hydrocarbons with molecular oxygen.

Continued on front page F-term (reference) 4G069 AA03 AA08 BA01A BA01B BA02A BA02B BB04A BB04B BC02A BC03A BC05A BC06A BC10A BC16A BC16B BC25A BC26A BC31A BC35A BC42A BC43A BC50A BC51A BC54ABCBC BCA BCBC BCA BCBC BC BC CB07 DA06 EA01X EA01Y FA02 4H006 AA02 AC42 BA02 BA05 BA06 BA07 BA08 BA09 BA10 BA12 BA13 BA14 BA15 BA16 BA19 BA20 BA21 BA30 BA31 BA33 BA35 BC10 BC13 BE30 BE60 4H039 CA60 CC30

Claims (2)

[Claims] 1. A method for synthesizing phenols by directly vapor-phase oxidizing an aromatic hydrocarbon with molecular oxygen to produce phenols, wherein a general formula (VxMo12-xCyOz) 100-a (SiO2) is used in the presence of water vapor.
a (where V is vanadium, Mo is molybdenum, C is phosphorus,
Antimony, bismuth, tellurium, chromium, tungsten, manganese, iron, cobalt, nickel, copper, zinc, magnesium, lanthanum, cerium, boron, aluminum, niobium, tantalum, titanium, zirconium, sodium, potassium, rubidium and cesium Si represents silicon, and O represents oxygen. The subscripts x, y, and z each represent an atomic ratio,
x is 1 to 12, y is 0 to 2, and z is a value determined according to the valence of another element. a represents% by weight, and 0.1 to 9
9.9. A method for producing phenols, comprising using the catalyst composition represented by the formula (1). 2. The method according to claim 1, wherein the reaction is carried out at a temperature of 400 to 700 ° C.