JPH04330944A - Catalyst for production of phenol, its production and production of phenol - Google Patents

Abstract

PURPOSE:To increase the rate of conversion of benzoic acid and the selectivity of phenol and to enhance the space time yield of phenol by the increased rate and selectivity. CONSTITUTION:Iron oxide and nickel oxide are contained in a catalyst in about 0.1-10.0 weight ratio of NiO to Fe2O3. When this catalyst is produced, iron oxide and nickel oxide are calcined at about 600-900 deg.C. Benzoic acid is subjected to vapor phase oxidation in the presence of the catalyst to produce phenol.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catalyst for producing phenol, a method for producing the catalyst, and a method for producing phenol by gas phase oxidation of benzoic acid in the presence of the catalyst.

0002

BACKGROUND OF THE INVENTION Conventionally, various methods and catalysts have been known for producing phenol by gas-phase catalytic oxidation of benzoic acid, and for catalysts used therein.

For example, JP-A No. 57-11932 discloses a catalyst comprising one or more of a copper compound, a vanadium compound, a silver compound, a lithium compound, a sodium compound, and a magnesium compound, and a catalyst using this catalyst. A method for producing phenol is disclosed.

[0004] Furthermore, Japanese Patent Publication No. 59-20384 discloses a method for producing phenol using a catalyst containing oxidized copper, zirconium, and an alkali metal supported on α-alumina. .

Furthermore, in Japanese Patent Publication No. 64-934,
Contains molybdenum as an essential component, and also contains at least one of vanadium, niobium, and tantalum, and at least one of copper, silver, manganese, iron, cobalt, nickel, rhodium, palladium, and platinum, and thallium, alkali metal, and alkaline earth. A method for producing phenol is disclosed that uses an oxide catalyst comprising a wide variety of metal elements, including at least one metal.

[0006]

[Problems to be Solved by the Invention] However, the catalyst disclosed in JP-A-57-11932 does not have sufficient activity and selectivity, and even in the process for producing phenol using this catalyst, benzoic acid Conversion rate 50.5%,
The highest phenol selectivity was 88.6%. In addition, when an exothermic reaction such as the oxidation reaction of benzoic acid is carried out using a catalyst containing a copper compound, hot spots are likely to occur in the catalyst layer, and the resulting sintering of the catalyst progresses, resulting in deterioration of activity. The problem was that there was a significant

[0007] Furthermore, the method for producing phenol disclosed in Japanese Patent Publication No. 59-20384 also has insufficient conversion rate and selectivity, with a maximum conversion rate of benzoic acid of 63.7%.
, the phenol selectivity was 82.2%. Furthermore, since many by-products such as diphenyl oxide are produced, a purification step for the produced phenol is required, which is economically disadvantageous.

Even in the production method disclosed in Japanese Patent Publication No. 64-934, the highest benzoic acid conversion rate was 75% and the highest phenol selectivity was 89%, which was not sufficient from an industrial perspective.

Furthermore, all of the above-mentioned production methods have poor productivity because the space-time yield of phenol (the amount of phenol produced per unit volume of catalyst and per unit time) is low.
It was extremely difficult to adopt it industrially.

The object of the present invention is to solve the above problems and provide a catalyst for producing phenol with high benzoic acid conversion rate and high phenol selectivity, and a method for producing phenol with high space-time yield. .

[0011]

[Means for Solving the Problems] In order to achieve the above object, the present inventors conducted intensive research and found that a catalyst for producing phenol by gas phase catalytic oxidation of benzoic acid was found.
The present inventors discovered that a catalyst containing iron oxide and nickel oxide has high activity and high selectivity, and also discovered that phenol can be produced with a high space-time yield by using this catalyst, and completed the present invention. .

That is, the catalyst for producing phenol of the present invention is characterized by containing iron oxide and nickel oxide.

[0013] Furthermore, the catalyst for producing phenol of the present invention is
Ratio of nickel oxide and iron oxide (NiO/Fe2O3
) is in the range of about 0.1 to 10.0 by weight.

[0014] Furthermore, in producing the catalyst for producing phenol of the present invention, a method for producing a catalyst for producing phenol is characterized in that a mixture containing iron oxide and nickel oxide is calcined at about 600 to 900°C. has been done.

Furthermore, the method for producing phenol of the present invention includes:
A method for producing phenol by gas-phase catalytic oxidation of benzoic acid, characterized in that the oxidation is carried out in the presence of a catalyst containing iron oxide and nickel oxide.

[0016] The ratio of nickel oxide to iron oxide (NiO/Fe2O3) contained in the catalyst is approximately 0.1 to 0.1 by weight.
A range of 10.0 is preferred. If the proportion of nickel oxide is greater than about 10.0, CO due to complete combustion
, CO2 production increases and phenol selectivity decreases. Furthermore, if the proportion occupied by nickel is less than about 0.1, benzene production becomes significant and the selectivity of phenol decreases.

The catalyst of the present invention may contain an alkali metal, an alkaline earth metal, or a compound thereof.
Furthermore, the catalyst of the present invention can also be used by supporting it on a catalyst carrier such as titanium oxide or silica.

The catalyst of the present invention can be produced by a general preparation method conventionally used for this type of catalyst. For example, nitrates, carbonates, organic acid salts, halides, hydroxides, oxides, etc. of iron and nickel can be used as raw materials.

As a method for mixing iron and nickel, a conventional precipitation method, kneading method, impregnation method, etc. can be used. Alternatively, iron oxide and nickel oxide may be powdered, mixed, and then compressed into pellets.

[0020] The catalyst is prepared at a temperature of about 600% in air or inert gas during the preparation step after mixing iron oxide and nickel oxide.
It is preferable to perform a firing treatment at ~900°C to crystallize one or more of iron oxide, nickel oxide, and composite oxide of iron and nickel. Generally, when a catalyst prepared by a conventional method is further calcined at a temperature of about 600° C. or higher, the specific surface area decreases and the catalytic activity decreases accordingly. However, the catalyst used in the present invention is
When the calcination temperature is in the range of about 600 to 900°C, the specific surface area decreases as the calcination temperature increases, but the phenol production activity improves, and a high benzoic acid conversion rate and high phenol selectivity can be obtained. When the calcination temperature is lower than about 600° C., only the CO and CO2 production reaction through complete combustion proceeds, hardly any phenol is produced, and carbonaceous substances are deposited on the catalyst surface. Also, the firing temperature is about 9
When the temperature is higher than 00°C, the conversion rate of benzoic acid is extremely low and the production of phenol is also very small.

Next, the method for producing phenol of the present invention will be explained. In the method of the present invention, oxygen is supplied together with benzoic acid as a raw material, and the oxygen to be supplied may be in a stoichiometric amount or more, preferably in a range of about 0.5 to 50 times the mole of benzoic acid as a raw material. When the amount of oxygen supplied is more than about 50 times the molar amount, complete oxidation of the raw material benzoic acid tends to occur. Also, if the amount of oxygen supplied is less than about 0.5 times the mole,
Unable to obtain sufficient benzoic acid conversion rate.

The oxygen to be supplied may be molecular oxygen, but air is generally used, and air may be diluted with an inert gas.

The reaction is generally carried out in the presence of water vapor, and the amount of water vapor supplied is preferably in the range of about 1 to 100 times the mole of benzoic acid used as the starting material. If the amount of water vapor supplied is more than about 100 times the mole, it is not economical;
When the amount is less than twice the mole, the selectivity of phenol generally decreases.

[0024] Space velocity is approximately 100 to 50,000 h-1
A range of is preferred. If the space velocity is less than about 100 h-1, sufficient space-time yield cannot be obtained;
When it is larger than 00h-1, the benzoic acid conversion rate becomes low.

[0025] The reaction temperature is preferably in the range of about 200 to 600°C, particularly preferably in the range of about 300 to 500°C. When the reaction temperature is higher than about 600°C, the selectivity of phenol decreases, and when the reaction temperature is lower than about 200°C, the benzoic acid conversion rate decreases.

The reaction pressure is not particularly limited as long as the feedstock remains in a gaseous state under the reaction conditions, but it is usually at normal pressure or slightly pressurized.

In the method of the present invention, either a fixed bed or a fluidized bed apparatus may be used.

[0028]

[Function] The catalyst for producing phenol of the present invention exhibits a high benzoic acid conversion rate and a high phenol selectivity for the synthesis of phenol by gas-phase catalytic oxidation of benzoic acid. shows high conversion and selectivity. Furthermore, the method for producing phenol of the present invention includes:
Produces phenol with high space-time yield.

[0029]

【Example】

I. Catalyst Preparation Examples 1 and 2 200 g of iron nitrate (Fe(NO3)3.9H2O) and 154 g of nickel nitrate (Ni(NO3)2.6H2O) were dissolved in 500 ml of ion-exchanged water, and approximately Dissolve 100g in 500ml of ion-exchanged water and add to 2L of ion-exchanged water at room temperature, pH 7-7.
It was dropped while maintaining the temperature at 8. After the dropwise addition was completed, stirring was continued for about 1 hour, and the precipitate formed was filtered and washed. Then, the cake-like substance was dried in air at 120°C for 24 hours,
This was baked in air at 800°C for 4 hours. The obtained catalyst had a weight ratio of NiO and Fe2O3 of 50:50.

Example 3 A catalyst was prepared in the same manner as in Example 1 using 59 g of nickel nitrate and 328 g of iron nitrate. The obtained catalyst had a weight ratio of NiO and Fe2O3 of 19:81.

Example 4 A catalyst was prepared in the same manner as in Example 1 using 108 g of nickel nitrate and 200 g of iron nitrate. The obtained catalyst had a weight ratio of NiO and Fe2O3 of 44:56.

Example 5 A catalyst was prepared in the same manner as in Example 1 using 202 g of nickel nitrate and 142 g of iron nitrate. The obtained catalyst had a weight ratio of NiO and Fe2O3 of 65:35.

Example 6 A catalyst was prepared in the same manner as in Examples 1 and 2 except that the calcination temperature was 700°C.

Example 7 A catalyst was prepared in the same manner as in Examples 1 and 2 except that the calcination temperature was 600°C.

Example 8 A catalyst was prepared in the same manner as in Examples 1 and 2 except that the calcination temperature was 500°C.

Example 9 A catalyst was prepared in the same manner as in Examples 1 and 2 except that the calcination temperature was 400°C.

Example 10 A catalyst was prepared in the same manner as in Examples 1 and 2 except that the calcination temperature was 1000°C.

Comparative Example 1 200 g of nickel nitrate dissolved in 500 ml of ion exchange water and about 100 g of sodium hydroxide dissolved in 500 ml of ion exchange water were added to 2 liters of ion exchange water while maintaining the pH at 7 to 8. dripped. After dropping, approx. 1
Stirring was continued for a period of time, and the resulting precipitate was filtered and washed. The cake-like material was then dried in air at 200°C for 24 hours, and then baked in air at 800°C for 4 hours.

Comparative Example 2 A catalyst was prepared according to Example 1 of Japanese Patent Publication No. 64-934.

Comparative Example 3 A catalyst was prepared according to Reference Example 1 of Japanese Patent Publication No. 59-20384.

Comparative Example 4 200 g of iron nitrate was dissolved in 500 ml of ion exchange water, and about 100 g of sodium hydroxide was dissolved in 500 ml of ion exchange water.
00ml and 2l of ion exchange water,
It was added dropwise while maintaining the temperature at H7-8. After the dropwise addition was completed, stirring was continued for about 1 hour, and the resulting precipitate was filtered and washed. The cake-like material was then dried in air at 120°C for 24 hours, and then baked in air at 800°C for 4 hours.

II. Experimental method The catalyst was crushed into a predetermined mesh and filled in a predetermined amount into a quartz tube with an inner diameter of 20 mm. Then, predetermined amounts of benzoic acid, water vapor, air, and nitrogen were supplied to this reaction tube, and the reaction was carried out at a predetermined temperature.

III. Experimental conditions and experimental results Example 1
The experimental conditions and experimental results for ~10 are shown in Table 1. Table 2 shows the experimental conditions and experimental results of Comparative Examples 1 to 4.

[0044]

[Table 1]

[0045]

[Table 2]

[0046]

[Table 3]

[0047]

Industrial Applicability According to the present invention, the conversion rate of benzoic acid and the selectivity of phenol can be increased, and phenol can be produced with a high space-time yield.

Claims (4)

[Claims] [Claim 1] A catalyst for producing phenol, characterized by containing iron oxide and nickel oxide. [Claim 2] The ratio of nickel oxide to iron oxide (Ni
The catalyst for producing phenol according to claim 1, wherein the weight ratio of O/Fe2O3) is in the range of about 0.1 to 10.0. 3. In producing the catalyst for producing phenol according to claim 1, about 60% of iron oxide and nickel oxide are used.
A method for producing a catalyst for producing phenol, which comprises firing at a temperature of 0 to 900°C. 4. A method for producing phenol by gas-phase catalytic oxidation of benzoic acid, the oxidation being carried out in the presence of the catalyst according to claim 1 or 2.