JPH07100387A - Improved titanosilicate catalyst, its production and organic synthesis reaction using the same as catalyst and utilizing hydrogen peroxide - Google Patents

Abstract

PURPOSE:To obtain a catalyst made of titanosilicate particles excellent in handleapility and activity by making pores of a specified size in a bonded body of primary titanosilicate particles. CONSTITUTION:Silicon oxide, titanium oxide and tetraalkylammonium hydroxide are brought into a reaction in the presence of water or steam to form primary titanosilicate particles and then the pH of the resulting reactive liq. is lowered to 5-10 to bond the particle to each other and to form aggregated titanosilicate particles. The objective titanosilicate catalyst is produced by firing the aggregated titanosilicate particles. This catalyst is a bonded body of primary titanosilicate particles and has pores of 50-300Angstrom size. As a result, titanosilicate particles excellent in handleability and activity can be obtd.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a catalyst which is active in a hydroxylation reaction of an aromatic compound using hydrogen peroxide as an oxidant, an epoxidation reaction of an olefin or an ammoximation reaction of a ketone, and a method for producing the same. Is.

[0002]

2. Description of the Related Art Titanosilicate is composed of xTi in which silicon of a crystal lattice is isomorphically substituted by titanium instead of aluminum.
It is a kind of zeolite having a crystal structure similar to that of ZSM-5 having a composition of O ₂ · (1-x) SiO ₂ , and its preparation method is disclosed by Taramasso et al. (USPat 4,4
10,501). Titanosilicate has been found to be active in the oxidation reaction of various organic compounds using hydrogen peroxide as an oxidant. For example, hydroxylation of aromatic compounds, epoxidation of olefins, oxidation of alkanes to form alcohols and ketones. It is known as a catalyst for production and ketoxime production by ammoximation of ketones.

The probability of the reaction substrate accessing the inside of the titanosilicate pores having high catalytic activity increases as the particle size of the catalyst decreases, and the diffusion distance of the product outside the pores is short. Therefore, in order to obtain a highly active catalyst, it is preferable that the diameter of the microcrystalline particles (hereinafter, referred to as primary particles) formed first in the production process is smaller, and in general, the particle diameter on the order of submicron is preferable. However, from a practical point of view, the smaller the primary particle size, the greater the difficulty in handling the catalyst, that is, the separation and recovery of the catalyst, and the advantage of the solid catalyst is lost.

Further, since the titanosilicate catalyst is synthesized using an expensive chemical, even if there is a slight loss in the synthesis process, the production cost is greatly affected, and it is necessary to recover it as completely as possible. is there. For that purpose, the formation of crystal particles (hereinafter referred to as secondary particles) in which the primary particles are formed by being bonded to each other and having a grown particle size is indispensable for practical use of the titanosilicate catalyst. Such secondary particles must be particles that retain the characteristics of the primary particles and have a good handling surface as a catalyst.

However, the titanosilicate secondary particles produced by the known method have mechanical properties because the titanosilicate primary particles are merely in physical contact with each other and are not bonded to each other. It has the disadvantage of low mechanical strength. When such a titanosilicate is used as a catalyst in the reaction, it is easily decomposed into primary particles and the handling properties such as filtration are deteriorated.

On the other hand, USP has a method for preparing a titanosilicate catalyst having excellent mechanical strength and handling properties.
at 4,701,428. According to the teaching of this method, the primary particles of titanosilicate are
0.05-0.11 in molar ratio to titanosilicate
By binding the silica oligomer added at a ratio of 1 as a binder, it becomes possible to prepare a titanosilicate catalyst having excellent mechanical strength and increased secondary particle size.

However, in this method, the titanosilicate powder obtained by hydrothermal synthesis is dispersed in a separately prepared solution of a silica oligomer in tetrapropylammonium hydroxide, and the slurry is further prepared using a device such as a spray dryer. Since it requires rapid drying, it has many problems such as many steps, expensive raw materials, and complicated operations and equipment. Further, in this method, the bonding portion between the primary particles is amorphous, and the structure is different from that of the crystalline primary particles, so that the mechanical strength is smaller than that of the crystalline portion. Further, there are cases in which disadvantages such as loss due to dissolution under alkaline conditions, further decrease in catalytic active sites per unit weight, and decrease in catalytic activity due to amorphous portion may occur.

[0008]

An object of the present invention is to provide titanosilicate particles having excellent handling properties and activity. Further, another object of the present invention is to provide a monohydric phenol by selective hydroxylation.
It is intended to provide a method for producing a polyhydric phenol, a method for producing an epoxy compound by selective epoxidation of an olefin, or a method for producing a ketoxime compound by a selective ammoximation reaction of a ketone.

[0009]

In view of the above problems, the present inventors have made earnest studies on a method for preparing a titanosilicate catalyst having excellent handling properties and mechanical strength and having high activity as a result of a simple method. In the method of preparing crystalline titanosilicate by hydrothermally synthesizing a sol containing titanium oxide and tetraalkylammonium hydroxide, which is a mold agent, in a method of preparing crystalline titanosilicate, The inventors have found that the object can be easily achieved by a simple method of lowering the pH of the synthesis reaction solution, and have completed the present invention.

The present invention provides a titanosilicate catalyst which is a combination of primary particles of titanosilicate and has pores of 50 to 300Å. Further, the present invention is a method in which a silicon compound, a titanium compound and a tetraalkylammonium compound as a molding agent are reacted in the presence of water or steam to form primary particles, and then the pH of the reaction solution is lowered to reduce the primary particles. Provided is a method for producing a titanosilicate catalyst, which comprises forming secondary particles in which particles are bonded to each other and then calcining the secondary particles.

The present invention will be described in detail below. The titanosilicate particles can be obtained by preparing a uniform reaction mixture (sol) consisting of a silicon compound, a titanium compound, a tetraalkylammonium compound as a template and water, and performing hydrothermal synthesis in an autoclave. The silicon compound which can be used here is tetraalkyl orthosilicate (Si (OR ₁ ) ₄ where R ₁ is C _{1 to} C
₅ represents an alkyl group), or colloidal silica or the like can be used. Tetraethyl orthosilicate is preferably used as the tetraalkyl orthosilicate. Examples of the titanium compound include tetraalkyl orthotitanate (Ti (OR ₂ ) ₄ , where R ₂ represents a C _{1 to} C ₅ alkyl group) and their oligomers, or TiO 2.
A hydrolyzable titanium halide compound such as Cl ₂ can be used.

As the tetraalkyl orthotitanate, tetraethyl orthotitanate, tetrapropyl orthotitanate and tetrabutyl orthotitanate are preferably used. The tetraalkylammonium compound used as a mold agent is a compound containing a tetraalkylammonium ion, and examples thereof include tetrapropylammonium hydroxide and tetrabutylammonium hydroxide. Most preferably, tetrapropylammonium hydroxide is used to prepare titanosilicate particles having a ZSM-5 structure.

When the titanosilicate particles in the present invention are prepared, the raw material is charged in a ratio of silicon compound / titanium compound = 5 to 500 (Si / Ti atomic ratio), nitrogen-containing compound / silicon compound = 0.2 to 0. 0.5 (N / Si atomic ratio), water / silicon compound = 10 to 100 (molar ratio). Primary particles are produced by carrying out a hydrothermal synthesis reaction in an autoclave using a sol obtained by removing hydrolysis products such as alcohol from the reaction mixture obtained by mixing the charged molar ratios.

The hydrothermal synthesis temperature for producing the primary particles is preferably by heating in a closed system to a temperature of 110 to 190 ° C, more preferably 160 to 180 ° C. If the heating temperature is lower than this temperature, it takes a long time to grow the primary particles, which is not practical. On the other hand, if the heating temperature is higher than this temperature, the catalytic activity decreases, which is not preferable. The hydrothermal synthesis time for producing the primary particles depends on the primary particle growth rate, but may be any time required for completing the growth of the primary particles, and is usually 1 to 10 days. If the process proceeds to the next step before the primary particles are not sufficiently formed, good catalyst properties cannot be obtained, which is not preferable. Moreover, after the growth of the primary particles is completed, even if the hydrothermal synthesis is continued at the same temperature, the primary particles do not have a remarkable effect, so that the above-mentioned time range is practically preferable.

The container used for the production of the primary particles is not particularly limited as long as it is a container of a material generally used in general, SU
An autoclave of S316, SUS304, titanium or the like is preferably used, but an inner surface of the container may be subjected to an inert treatment such as Teflon lining or glass lining. The temperature distribution inside the autoclave is important, and a structure having a structure that realizes a temperature distribution as uniform as possible is preferable. Also, during the hydrothermal synthesis, a preferable catalyst can be obtained by performing stirring with an appropriate means to realize a uniform temperature distribution.

The pH of the hydrothermal synthesis mother liquor at the time when the primary particles are formed is usually 11 or more.
In the region, the produced primary particles are in a slurry state in which they are uniformly dispersed in the solution, and its handling is extremely difficult. In the present invention, the p of the slurry of such primary particles is
By lowering H, secondary particles that are easy to handle and have high catalytic activity can be obtained.

PH of hydrothermal synthetic mother liquor in which primary particles are formed
One way to reduce the is the addition of acid. In this method, when the production of primary particles is completed, a hydrothermal synthetic solution in the form of a slurry is taken out from the reaction vessel, and an appropriate acid is added thereto with stirring to lower the pH.
As a result, primary particles are bonded to each other to obtain secondary particles having a grown particle size. The acid used here may be an inorganic acid or an organic acid and is not particularly limited.

More specifically, suitable inorganic acids include hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, hydrofluoric acid and the like, and suitable organic acids include formic acid, acetic acid, propionic acid, tartaric acid, Examples include malic acid, lactic acid, phthalic acid, benzoic acid and the like. In order to prevent the pH of the reaction solution from rapidly decreasing locally, it is preferable to use these acids after diluting them to an appropriate concentration.

The acid is added with stirring while monitoring the pH of the slurry solution, and the addition is terminated when the pH becomes 10 or less. In this case, if the addition amount is too large and the pH is lowered too much, dispersion of the primary particles is caused. Therefore, the acid is added so that the pH does not fall below 5, preferably the pH does not fall below 7. Then, stirring is continued for 5 minutes to 5 hours, more preferably 1 to 2 hours, until sufficient secondary particle growth occurs. The solution may be heated to 40 to 100 ° C. to increase the growth reaction rate of secondary particles and shorten the stirring time.

When the hydrothermal synthesis temperature is raised from the primary particle formation temperature to a higher temperature, the tetraalkylammonium ion, which is a mold agent, is thermally decomposed, and the pH of the solution is 7
It drops to -10. As a result, primary particles are bonded to each other to form secondary particles having a grown particle size. The temperature required for the formation of the secondary particles may be a temperature required for the tetraalkylammonium ion to decompose at a sufficient rate to reduce the pH of the solution to 7 to 10, which is usually 20.
It is 0 ° C or higher. The preferred temperature range is 200-250 ° C
And more preferably 200 to 220 ° C. If the temperature is lower than this range, it takes a long time to decompose the tetraalkylammonium ion, which is not practical, and if the temperature is higher than this range, the effect of shortening the time is not so remarkable.

The thermal decomposition amount of tetraalkylammonium hydroxide can be known by monitoring the pressure increase due to alkylene produced by the decomposition. The time for maintaining the secondary particle growth temperature may be the time required for decomposition of the tetraalkylammonium hydroxide, and is usually 1 to 10 days. If the process proceeds to the next step before the secondary particles are sufficiently generated, good catalyst characteristics cannot be obtained, which is not preferable. Further, after the growth of the secondary particles is completed, the secondary particles do not have a remarkable effect even if they are continued at the same temperature, so that the above-mentioned time range is practically preferable.

Solid titanosilicate is separated from the reaction solution containing the secondary particles grown by the above method. However, since the solid titanosilicate is sufficiently grown, it is filtered or centrifuged under mild conditions. Easily separated by. After washing the obtained titanosilicate particles, at 1 to 450-650 ° C.
100 hours, more preferably 5 to 500-600 ℃
A titanosilicate catalyst can be manufactured by baking for 10 hours.

The titanosilicate catalyst produced by the above method usually has a median particle size distribution (particle size distribution in which smaller particles are 50% by weight of the total particle size) is 1 μm or more. Furthermore, the particle size distribution median is preferably 5 by allowing sufficient secondary particle formation time.
It can be set to μm or more. Particle size distribution median is 10
A titanosilicate catalyst having a size of not less than μm is most preferable from the viewpoint of handling or catalytic activity.

The titanosilicate catalyst of the present invention has pores (mesopores) of 50 to 300 Å corresponding to the gaps formed by the bonding of the primary particles. Further, the titanosilicate catalyst produced by the conventional method generally has no pores other than the 5.4Å × 5.6Å micropores unique to the titanosilicate primary particles. This is confirmed by measuring the pore distribution. A titanosilicate catalyst having no pores (mesopores) of 50 to 300 Å has poor catalytic activity.

The titanosilicate catalyst of the present invention shows a clear diffraction pattern in the X-ray diffraction analysis and no characteristic scattering is observed in the presence of the amorphous portion, so that the titanosilicate catalyst of the present invention is obtained. It is clear that is essentially only crystalline. Furthermore, according to SEM observation, the secondary particles of the titanosilicate catalyst of the present invention are crystalline particles in which primary particles having a particle diameter of 0.05 to 0.3 μm are bonded together.

The titanosilicate catalyst of the present invention is preferably used for the production of a dihydric phenol by reacting a monohydric phenol with hydrogen peroxide and gives a specific dihydric phenol by selective hydroxylation. Para-selective hydroxylation gives hydroquinone in high yields, especially when the monohydric phenol is phenol.

The production of hydroquinone by the reaction of phenol and hydrogen peroxide is carried out as follows. That is, phenol and hydrogen peroxide are added in the presence of the titanosilicate catalyst of the present invention and a solvent. The solvent is preferably a polar solvent such as alcohol, ketone or water, and most preferably water. The amount of the solvent used is not limited, but is preferably 10 to 50% by weight, more preferably 20% by weight of the whole reaction mixture.
-40% by weight. The use ratio of phenol to hydrogen peroxide is 2 times mol or more to suppress side reactions,
More preferably, it is 3 times or more moles. Furthermore, it is preferable to add dioxane to the reaction mixture for para-selective hydroxylation, and the amount used is 0.04 to 1.2 times mol of monohydric phenol, preferably 0.1 to 0.8. It is twice the mole. When it is less than this range, sufficient para selectivity cannot be obtained, and when it is more than this range, the yield of hydroquinone decreases.

The reaction temperature is 50 to 150 ° C., preferably 6
It is 0 to 120 ° C. When the reaction temperature is lower than this range, the reaction rate is low, and when it is higher than this range, the production of high-boiling substances is increased due to side reactions. Hydrogen peroxide is commercially available 30
A 60% by weight aqueous solution is preferably used. As for the addition of hydrogen peroxide to the reaction system, the whole amount thereof may be added at once,
It may be added stepwise in parallel with the progress of the reaction. The titanosilicate catalyst is usually used in an amount of 0.1 to 1 with respect to the reaction mixture.
An amount corresponding to 0% by weight, preferably 1 to 5% by weight is used.

The titanosilicate catalyst of the present invention also comprises
It is preferably used for the production of an epoxy compound by the reaction of an olefin and hydrogen peroxide, and gives a specific epoxy compound by selective epoxidation. In particular, when the olefin is an allyl ester of unsaturated carboxylic acid, the selective epoxidation provides a high yield of glycidyl ester of unsaturated carboxylic acid. Examples of the allyl ester of unsaturated carboxylic acid include allyl acrylate, allyl methacrylate, and allyl cinnamate.

The production of an unsaturated carboxylic acid glycidyl ester by the reaction of an unsaturated carboxylic acid allyl ester (hereinafter referred to simply as "allyl ester") with hydrogen peroxide is carried out as follows. That is, allyl ester and hydrogen peroxide are added in the presence of the titanosilicate catalyst of the present invention and a solvent. As the solvent, alcohol, ketone,
A polar solvent such as water is preferable, and methanol and acetone are particularly preferable. Although the amount of the solvent used is not limited, it is preferably 20 to 60% by weight, more preferably 30 to 40% by weight, based on the whole reaction mixture. If it is less than this range, the yield will be decreased, and if it is more than this range, the recovery energy of the solvent will be increased.

The use ratio of allyl ester to hydrogen peroxide is 1 times or more, more preferably 2 to 10 times by mole. When it is less than this range, side reactions increase, and when it is more than this range, recovery energy of allyl ester increases.

The reaction temperature is 30 to 100 ° C., preferably 5
It is 0 to 70 ° C. When the reaction temperature is lower than this range, the reaction rate is low, and when it is higher than this range, side reactions increase. As the hydrogen peroxide, a commercially available 30-60 wt% aqueous solution is preferably used. The hydrogen peroxide may be added to the reaction system all at once, or may be added stepwise in parallel with the progress of the reaction. The titanosilicate catalyst is usually 0.1 to 10% by weight, preferably 1
An amount corresponding to ~ 5% by weight is used.

The titanosilicate catalyst of the present invention further comprises
It is preferably used for producing a ketoxime compound by reacting a ketone, ammonia and hydrogen peroxide, and gives a specific ketoxime compound by ammoximation. Especially when the ketone is cyclohexanone, selective ammoximation gives cyclohexanone oxime in high yield.

The ketoxime compound is produced by the reaction of ketone, ammonia and hydrogen peroxide as follows. That is, ketone, ammonia and hydrogen peroxide are added in the presence of the titanosilicate catalyst of the present invention and a solvent. As the solvent, polar solvents such as alcohol, ketone and water are preferable, and t-butyl alcohol is particularly preferable.
Although the amount of the solvent used is not limited, it is preferably 10 to 50% by weight based on the whole reaction mixture. If it is less than this range, the yield will be decreased, and if it is more than this range, the recovery energy of the solvent will be increased.

The use ratio of hydrogen peroxide to ketone is
0.5 to 1.5 times mol, more preferably 0.5 to 1.2
It is twice the mole. The use ratio of ammonia to the ketone is 1 times or more, and more preferably 1.5 times or more. If the ratio of ammonia to ketone used is less than this range, side reactions will increase.

The reaction temperature is 30 to 120 ° C., preferably 6
It is 0 to 100 ° C. The reaction pressure is atmospheric pressure or under pressure so that the concentration of ammonia in the solution does not become too low. As the hydrogen peroxide, a commercially available 30-60 wt% aqueous solution is preferably used. The hydrogen peroxide may be added to the reaction system all at once, or may be added stepwise in parallel with the progress of the reaction. The titanosilicate catalyst is usually 0.1 to 10% by weight, preferably 1
An amount corresponding to ~ 5% by weight is used.

[0037]

The present invention will be described in more detail below with reference to specific examples, but these examples do not limit the scope of the present invention to any mode. The evaluation method is as follows.

[Pore distribution measuring method] The adsorption and desorption isotherms of nitrogen gas on the catalyst at the liquid nitrogen temperature were determined from vacuum to liquid nitrogen temperature based on "Adsorption" by Tomicho Keiitani (Kyoritsu Shuppan, 1965). It was measured over the saturated vapor pressure of nitrogen gas. The adsorption amount at a certain pressure in the above range is given by the sum of the adsorption of the polylayer on the solid surface and the capillary condensation into the pores. The pore distribution was determined by the Cranston-Inkley method, assuming that each pore was approximated by a cylinder. [Mechanical Strength Evaluation Method] The titanosilicate catalyst was placed in a tank equipped with an ultrasonic generator having a frequency of 39 kHz and an output of 40 W, and ultrasonic waves were applied for 30 minutes to give mechanical external force to the particles, and then the particle size distribution was again obtained. Was measured.

[SEM Observation Method] A small amount of a titanosilicate catalyst was fixed on a double-sided tape on a brass jig, and after vapor deposition of gold, it was magnified 10,000 to 25,000 times and observed by SEM. [Particle size distribution measurement method] Water and a titanosilicate catalyst were placed in a stirring tank equipped with an ultrasonic generator, and ultrasonic waves were irradiated for 10 minutes to sufficiently disperse the particles, and then the dispersion slurry was pumped using a laser. It was circulated in an optical cell equipped with a diffractometer. The particle size distribution was obtained from the laser diffraction intensity distribution using both Fraunhofer theory and Mie scattering theory.

Example 1 Tetraethyl orthosilicate (375 g) and tetraethyl orthotitanate (10.3 g) were placed in a 3-liter four-necked separable flask, and 648 g of a 20% by weight aqueous tetrapropylammonium hydroxide solution was added using a dropping pump under a nitrogen stream. Was added dropwise at a rate of 5.4 g / min. The temperature of the reaction solution was adjusted to be constant at 20 ° C. throughout the dropping. After completion of the dropwise addition, stirring was continued for a while to allow the hydrolysis to proceed completely, and then the reaction solution was heated to 80 ° C. to distill off ethanol produced by the hydrolysis from the reaction solution to obtain a transparent sol. 290 g of distilled water was added to the obtained sol, and the total weight of the solution was 885 g, and the solution was filled in a 3 liter autoclave made of SUS316 at a filling rate of 30%. P of this sol
H was 11.4. After replacing the gas in the autoclave with nitrogen, it was sealed and heated at 170 ° C. for 2 days, then 20
The temperature was raised to 0 ° C., kept at 200 ° C. for another 2 days, and then cooled to room temperature.

The liquid containing the white solid was mixed with a centrifuge 3
Centrifugation was carried out at 000 rpm for 20 minutes to separate almost transparent supernatant liquid and white titanosilicate particles. The pH of the supernatant was 9.2. The obtained white titanosilicate particles were washed with distilled water, dried, and calcined in an electric furnace in air at 550 ° C. for 6 hours to obtain 91.7 g of a titanosilicate catalyst. This was a yield of 82% based on the used alkoxide raw material.

When the particle size distribution of this catalyst was measured, the median particle size distribution was about 18 μm as shown in FIG. In FIG. 1, the under-sieve% means the weight% of particles having a certain particle diameter or less in the whole. According to SEM observation, the secondary particles were densely packed with substantially spherical primary particles having an average particle size of 0.1 μm, and the binding part between the primary particles was crystalline. When the pore distribution was measured, 100 to 300 Å pores corresponding to the gaps formed by the bonding of the primary particles were recognized. When the mechanical strength of this catalyst was evaluated, secondary particles having a particle size of 10 μm or less after irradiation with ultrasonic waves accounted for 29.4% of the whole.
To 32.3% (increasing rate of 10%).

Example 2 Using the catalyst obtained in Example 1, a hydroxylation reaction of phenol was carried out. That is, 6.5 g of the titanosilicate catalyst obtained in Example 1, 250 g of phenol,
42 g of 1,4-dioxane and 150 g of water were charged into a four-necked flask having a volume of 1 liter equipped with a stirrer, heated to 80 ° C., and 72 g of 31 wt% hydrogen peroxide solution was added dropwise.
As a result of analyzing the solution after continuing the reaction for 3 hours, the yield of the dihydric phenol based on hydrogen peroxide was 77%, the hydroquinone / catechol molar ratio was 5.7, and hydroquinone was selectively obtained.

Example 3 Tetraethyl orthosilicate (375 g) and tetraethyl orthotitanate (10.3 g) were placed in a 3-liter four-necked separable flask, and 648 g of a 20 wt% tetrapropylammonium hydroxide aqueous solution was added under a nitrogen stream using a dropping pump. Was added dropwise at a rate of 5.4 g / min. The temperature of the reaction solution was adjusted to be constant at 20 ° C. throughout the dropping. After completion of the dropwise addition, stirring was continued for a while to allow hydrolysis to proceed completely, and then the reaction solution was heated to 80 ° C. to distill ethanol generated by hydrolysis from the reaction solution. To the obtained transparent sol, 290 g of distilled water was added, and the total weight of the solution was adjusted to 8
85 g was filled in a 3 liter autoclave made of SUS316 at a filling rate of 30%. The pH of this sol is 11.
It was 4. After replacing the gas in the autoclave with nitrogen, the autoclave was sealed, heated at 170 ° C. for 2 days, and then cooled.

A portion of the obtained white emulsion (69 g) was weighed out, and an aqueous acetic acid solution was gradually added dropwise while stirring. The pH of the solution was lowered to 8 and stirring was continued for a while. Centrifuge the solution at 3000 rpm for 20 minutes,
A clear supernatant and a white solid were separated. The solid obtained is washed with distilled water, dried and then heated in an electric furnace at 550 ° C. for 6 hours in air.
A time-dependent calcination treatment was performed to obtain a titanosilicate catalyst. When the particle size distribution of the catalyst thus obtained was measured, the median particle size distribution was 17 μm. According to SEM observation, the secondary particles were densely packed with substantially spherical primary particles having an average particle size of 0.1 μm, and the binding part between the primary particles was crystalline. When the pore distribution was measured, 100 to 250 Å pores corresponding to the gaps formed by the binding of the primary particles were recognized. When the mechanical strength of this catalyst was evaluated, after irradiation with ultrasonic waves, secondary particles with a particle size of 10 μm or less accounted for 2% of the total.
It increased from 6.4% to 29.6% (12% increase rate).

Example 4 Using the catalyst obtained in Example 3, hydroxylation of phenol was carried out in the same manner as in Example 2. Dihydric phenol yield 74%, hydroquinone / catechol ratio 5.
7, which was a good reaction result.

Example 5 The amount of tetraethyl orthotitanate was 5.1 g,
898 g of sol was prepared in the same manner as in Example 1 except that the Si / Ti ratio was 80. This sol was filled in a 3 liter autoclave made of SUS316 at a filling rate of 30%. The pH of this sol was 11.5. 17 after sealing
The mixture was heated to 0 ° C., heated to 200 ° C. after 4 days, kept at that temperature for 2 days, and then cooled to room temperature. The liquid containing the white solid was centrifuged at 2500 rpm for 20 minutes using a centrifuge to separate the white solid. The pH of the supernatant is 9.7
Met. After washing the obtained white solid with ion-exchanged water,
It was dried and calcined at 550 ° C. for 12 hours in air in an electric furnace to obtain 72 g of a titanosilicate catalyst. This was a yield of 66% based on the used alkoxide raw material.

The median particle size distribution of the obtained catalyst is 21 μm.
It was m. According to SEM observation, the secondary particles were densely packed with substantially spherical primary particles having an average particle size of 0.1 μm, and the binding part between the primary particles was crystalline.
When the pore distribution was measured, 100 to 250 Å pores corresponding to the gaps formed by the binding of the primary particles were recognized. The mechanical strength of this catalyst was evaluated to be 10 after ultrasonic irradiation.
Secondary particles with a particle size of less than μm account for 27.4% to 3% of the total.
It increased to 0.7% (12% increase rate).

Example 6 Using the catalyst obtained in Example 5, hydroxylation of phenol was carried out in the same manner as in Example 2. As a result, the yield of dihydric phenol based on hydrogen peroxide was 80%, and the produced hydroquinone was obtained. The / catechol molar ratio was 7.2.

Example 7 Using the titanosilicate catalyst obtained in Example 1, an epoxidation reaction of an allyl ester was carried out. That is, 4.4 g of the titanosilicate catalyst obtained in Example 1, 80 g of allyl methacrylate, and 60 g of methanol were charged into a three-necked flask having a volume of 200 ml equipped with a stirrer and heated to 60 ° C. % Hydrogen peroxide water 1
8.3g was added. As a result of analyzing the solution after continuing the reaction for 3 hours, the hydrogen peroxide conversion rate was 96%, the hydrogen peroxide-based glycidyl methacrylate selectivity was 85%, and the converted allyl methacrylate-based glycidyl methacrylate selectivity was 9%.
It was 7%. Most of the by-products were epoxidized compounds having an unsaturated bond of methacryloyl group, and the produced amount was 1/44 molar amount with respect to glycidyl methacrylate.

Example 8 Using the titanosilicate catalyst obtained in Example 3, an ammoximation reaction of a ketone was carried out. That is, 4.0 g of the titanosilicate catalyst obtained in Example 3, 39.6 g of 25 wt% aqueous ammonia solution, and cyclohexanone 3
8.3 g and 59 g of t-butyl alcohol were charged into an autoclave made of 316 having a volume of 300 ml equipped with a stirrer, heated to 80 ° C., and then 44.7 g of 31 wt% hydrogen peroxide solution was used for 1 hour using a pump. Added. After the addition was completed, stirring was continued for 30 minutes. After the catalyst was filtered off, acetone was added to make a homogeneous solution, and the reaction solution was analyzed by gas chromatography or iodometric titration.
The hydrogen peroxide standard yield of cyclohexanone oxime is 83
%, And the cyclohexanone standard yield of cyclohexanone oxime was 87%.

Comparative Example 1 The same hydrothermal synthesis operation as in Example 1 was carried out except that the hydrothermal synthesis temperature was kept at 170 ° C. and kept constant for 4 days. After cooling 3
Centrifugation was performed at 000 rpm for 20 minutes. Precipitation of the titanosilicate particles was very slight and most of the titanosilicate particles remained dispersed in the liquid. The residual liquid after separating the precipitate is in the form of a slurry in which primary particles are dispersed,
Its pH was 11.7. The precipitate was filtered off, Example 1
The same washing and calcination treatments were carried out to obtain a titanosilicate catalyst. The obtained solid is referred to as catalyst A. The yield of the catalyst A based on the raw material alkoxide was 10%. The median particle size distribution of catalyst A was 13 μm.

A slurry-like liquid obtained by separating the catalyst A was added to 8000
When strong centrifugation was performed at 120 rpm for 120 minutes, white titanosilicate particles were separated from the liquid.
Thereafter, the same washing and baking treatments as in Example 1 were carried out to obtain a titanosilicate catalyst. The obtained solid is referred to as catalyst B.
The yield of the catalyst B based on the raw material alkoxide was 82%. The median particle size distribution of catalyst B was 21.7 μm.

According to SEM observation, both the catalyst A and the catalyst B were aggregates of primary particles which were separated from each other independently, and binding of primary particles was not observed. According to the measurement of the pore size distribution, the obtained catalyst A and catalyst B were both 5.4Å × 5.6 peculiar to the titanosilicate primary particles.
Other than Å micropores, 50 to 300 Å pores corresponding to the gaps formed by the bonding of the titanosilicate primary particles were not recognized. When the mechanical strengths of catalyst A and catalyst B were evaluated, the destruction of particles proceeded in both cases, and accounted for 10% of the total.
Secondary particles having a particle size of less than or equal to μm increased from 21.9% to 39.4% in Catalyst A (80% increase rate) and 2 in Catalyst B.
It increased from 1.9% to 29.3% (increase rate of 34%).

Comparative Example 2 The catalyst A obtained in Comparative Example 1 was used to hydroxylate phenol in the same manner as in Example 2. As a result, the hydroquinone / catechol ratio was 5.3, but the dihydric phenol was used. Yield dropped to 56%.

Comparative Example 3 A sol was obtained in the same manner as in Example 1, the sol was charged into an autoclave, heated at 200 ° C., and then held at 200 ° C. for 4 days, and heated as in Example 1. A supernatant and a white solid were obtained. The pH of the supernatant was 9.7. The white solid was washed and calcined in the same manner as in Example 1 to obtain 27 g of a titanosilicate catalyst. This was a yield of 24% based on the used alkoxide raw material. The particle size distribution of this catalyst was almost the same as that of Example 1, and the median particle size distribution was 17 μm.

According to SEM observation, the obtained catalyst was an aggregate of primary particles which were separated from each other,
No binding between primary particles was observed. According to the measurement of the pore size distribution, the obtained catalyst had a micropore size of 5.4 Å × 5.6 Å, which is unique to the titanosilicate primary particles, and 50 to 50, which corresponded to the gaps formed by the binding of the titanosilicate primary particles. No 300Å pores were observed.

Comparative Example 4 Using the catalyst obtained in Comparative Example 3, hydroxylation of phenol was carried out in the same manner as in Example 2. As a result, the yield of dihydric phenol was 67% and the hydroquinone / catechol ratio was 5. It was 4.

Comparative Example 5 A titanosilicate was obtained in the same manner as in Example 1 except that the sol prepared by the same procedure as in Example 1 was charged into an autoclave, heated at 175 ° C., and kept at 175 ° C. for 10 days. It was The median particle size distribution of the obtained titanosilicate secondary particles was 6.1 μm. Next, this catalyst was granulated with a binder based on a silica oligomer by the following method. That is, 17 g of titanoethyl orthosilicate
20% by weight tetrapropylammonium hydroxide aqueous solution (14.2 g) was added dropwise and hydrolyzed to prepare a silica sol. 5 g of the titanosilicate was added to the homogeneous sol.
Was added and stirred for 1 hour. After removing the supernatant liquid, it was dried and calcined in an electric furnace in air at 550 ° C. for 6 hours to obtain 9 g of a white titanosilicate catalyst.

The median particle size distribution of the secondary particles of the obtained catalyst was 48 μm. According to SEM observation, the binding part between the primary particles is amorphous, and the secondary particles have an average particle size of 0.1.
The μm primary particles were bonded to each other through the amorphous portion. According to the measurement of the pore size distribution, the obtained catalyst had a micropore size of 5.4 Å × 5.6 Å, which is unique to the titanosilicate primary particles, and 50 to 50, which corresponded to the gaps formed by the binding of the titanosilicate primary particles. No 300Å pores were observed. When the mechanical strength of the obtained catalyst is evaluated, the secondary particles having a particle size of 10 μm or less in the whole are
It increased from 6.5% to 12.4% (increase rate 91%).

Comparative Example 6 Using the catalyst obtained in Comparative Example 5, the hydroxylation of phenol was carried out in the same manner as in Example 2. As a result, the yield of dihydric phenol based on hydrogen peroxide was 68%, and the produced hydroquinone was obtained. The / catechol molar ratio was 4.4, which was lower than that of Example 1.

Comparative Example 7 The catalyst A obtained in Comparative Example 1 was used to carry out the hydroxylation reaction of the allyl ester in the same manner as in Example 7. As a result, the hydrogen peroxide conversion rate was 61%, based on hydrogen peroxide. The glycidyl methacrylate selectivity was 74%, and the glycidyl methacrylate selectivity based on the converted allyl methacrylate was 81%.

Comparative Example 8 Using the catalyst B obtained in Comparative Example 1, the hydroxylation reaction of the allyl ester was carried out in the same manner as in Example 7. As a result, the hydrogen peroxide conversion rate was 96%, based on hydrogen peroxide. The selectivity of glycidyl methacrylate was 82%, and the selectivity of glycidyl methacrylate based on the converted allyl methacrylate was 87%.

Comparative Example 9 Using the catalyst B obtained in Comparative Example 1, the ammoximation reaction of cyclohexanone was carried out in the same manner as in Example 8. As a result, the hydrogen peroxide standard yield of cyclohexanone oxime was 73%, The cyclohexanone oxime had a cyclohexanone standard yield of 74%.

[0065]

According to the present invention, a titanosilicate catalyst having excellent handling characteristics and catalytic activity is provided.
In the production of the catalyst of the present invention, the formation of secondary particles is achieved by adding an acid to the reaction solution after the production of primary particles or by performing it in a temperature range higher than the primary particle production temperature, and conventional equipment is used. Since it is a simple method, it is industrially important because it is extremely easy to carry out industrially.

Further, by using the titanosilicate catalyst of the present invention as a reaction catalyst, a method for producing a dihydric phenol by selective hydroxylation of a monohydric phenol with hydrogen peroxide, a selective olefin with hydrogen peroxide A method for producing an epoxy compound by various epoxidations, or a method for producing a ketoxime compound by a selective ammoximation reaction of a ketone, ammonia, and hydrogen peroxide is provided.

[Brief description of drawings]

1 is a particle size distribution of the titanosilicate catalyst obtained in Example 1. FIG.

Claims (12)

[Claims] 1. A titanosilicate catalyst, which is a combination of primary particles of titanosilicate and has pores of 50 to 300 Å. 2. The titanosilicate catalyst according to claim 1, wherein the binding part between the primary particles is crystalline. 3. The titanosilicate catalyst according to claim 1, wherein the median particle size distribution is 10 μm or more. 4. A silicon oxide, a titanium oxide and a tetraalkylammonium hydroxide are reacted in the presence of water or steam to form primary particles of titanosilicate, and then the pH of the reaction solution is adjusted to 5 A method for producing a titanosilicate catalyst, characterized in that secondary particles of titanosilicate in which primary particles are bound to each other are formed by lowering to 10 and then the formed secondary particles are calcined. 5. The method for producing a titanosilicate catalyst according to claim 4, wherein the method for lowering the pH in forming the secondary particles is to add an acid to the reaction solution. 6. The method for producing a titanosilicate catalyst according to claim 4, wherein the method of lowering the pH in forming the secondary particles is to heat the reaction solution to 200 ° C. or higher. 7. The temperature for forming secondary particles is 200 to 250 ° C.
7. The method for producing a titanosilicate catalyst according to claim 6, wherein 8. In the production of a dihydric phenol by the reaction of a monohydric phenol and hydrogen peroxide, the primary particles of titanosilicate are bound to each other and have pores of 50 to 300 Å. A method for producing a dihydric phenol, which comprises using a titanosilicate catalyst as a reaction catalyst. 9. In the production of an epoxy compound by the reaction of an olefin and hydrogen peroxide, a titanosilicate, which is a combination of primary particles of titanosilicate and has pores of 50 to 300 Å. A method for producing an epoxy compound, which comprises using a catalyst as a reaction catalyst. 10. The method for producing an epoxy compound according to claim 9, wherein the olefin is an allyl ester of an unsaturated carboxylic acid. 11. A method for producing a ketoxime compound by the reaction of a ketone, ammonia and hydrogen peroxide, which is a combination of primary particles of titanosilicate, 50 to 3
A process for producing a ketoxime compound, which comprises using a titanosilicate catalyst having a pore size of 00Å as a reaction catalyst. 12. The method for producing a ketoxime compound according to claim 11, wherein the ketone is cyclohexanone.