JP2001089408A - Method of producing dihydroxy-diphenyl ether - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of efficiently producing 4,4'-dihydroxy-diphenyl ether or 3,3'-dihydroxy-diphenyl ether which is an extremely useful compound having wide applications as an epoxy resin, a polycarbonate resin, a polyester resin, a liquid crystal polymer or various kinds of organic synthetic intermediates, etc., by subjecting hydroquinone or resorcinol to a one-stage reactional operation. SOLUTION: Hydroquinone or resorcinol is subjected to a dehydration condensing reaction using a high-silica mordenite or a high-silica Y-type zeolite as a catalyst. The reaction is carried out in the presence of the high-silica mordenite in >=40 (silica/alumina) ratio or the Y-type zeolite catalyst in >=40 (silica/alumina) ratio.

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 dihydroxy-diphenyl ether, and more particularly to a novel method for producing dihydroxy-diphenyl ether by dehydration-condensation of dihydroxy-benzene. The dihydroxy-diphenyl ether produced by the method of the present invention is a very useful compound having a wide range of uses as an epoxy resin, a polycarbonate resin, a polyester resin, a liquid crystal polymer, or various organic synthetic intermediates.

[0002]

2. Description of the Related Art A conventional method for producing dihydroxy-diphenyl ether is to react parachlorophenol or parabromophenol with a phenolate of hydroquinone at a high temperature, and then neutralize the reaction mixture to obtain a stoichiometric amount of sodium chloride or odor. There is known a method of producing while producing sodium chloride. Alternatively, a method of heating hydroquinone with zinc chloride in isovaleric acid {Ber. , 74 ,
1851, 1853, 1862 (1941)}; 4,
A method in which 4′-dichlorodiphenyl ether or 4,4′-dibromodiphenyl ether is heated to 210 ° C. under pressure in a methanol-NaOH solution in the presence of a copper catalyst {DRP. 609080 (1932)}; a method of reacting 4,4′-diamino-diphenyl ether with nitrite to form a diazonium salt and then decomposing it {J. Am. Chem. Soc., 6
8 , 1894 (1946)｝ and the like.

[0003]

As described above, the conventionally known method for producing dihydroxy-diphenyl ether requires a multi-step synthesis process for producing a starting material, or requires an expensive precursor. There are difficulties such as.
Others have problems such as the use of corrosive auxiliary materials or by-products of stoichiometric amounts of salts such as sodium chloride, and are not suitable for industrially producing large amounts of dihydroxy-diphenyl ether. hard.

An object of the present invention is to provide a method for producing dihydroxy-diphenyl ether which does not have the above-mentioned difficulties and problems, or a method for producing dihydroxy-diphenyl ether which is industrially advantageous.

[0005]

The present inventor has conducted various studies on a method for producing dihydroxy-diphenyl ether which does not have the above-mentioned difficulties and problems. As a result, it was found that dihydroxy-benzene such as hydroquinone or resorcinol was dehydrated and condensed using high silica mordenite or high silica Y-type zeolite as a catalyst, and dihydroxy-diphenyl ether was obtained efficiently, and there was no problem as in the conventional method. The present invention has been completed.

That is, the gist of the present invention is to produce dihydroxy-diphenyl ether by dehydration-condensation of dihydroxy-benzene (silica / alumina).
The reaction is carried out in the presence of a high silica mordenite having a ratio of 40 or more or a Y-type zeolite catalyst having a (silica / alumina) ratio of 40 or more.

Thus, the mordenite is made of Na ₈ (Al ₈ S
i ₄₀ O ₉₆ ) is a crystalline aluminosilicate represented by 24H ₂ O. Ordinary mordenite, natural or synthetic, has a Si / Al ratio of around 5, (silica /
(Alumina) ratio, that is, (SiO ₂ / Al ₂ O ₃ ), which is around 10 and greatly exceeds 11 in silica / alumina ratio, is a special synthetic product, or deoxidized by acid treatment, steam treatment or the like. Nothing is known other than the one with aluminum.

The mordenite used in the method of the present invention has a silica / alumina ratio of 40 or more. Those having a high silica / alumina ratio have the advantage of less precipitation of tar or carbon when used in the reaction and little reduction in catalytic activity due to this, but too high a silica / alumina ratio is a catalytically active point. Usually, the range of 40 to 300, preferably 90 to 300, more preferably 150 to 300 is frequently used, since the catalytic activity is lowered due to the decrease of the acid point.

If the silica / alumina ratio is 40 or more,
The mordenite can be obtained by repeatedly subjecting ordinary mordenite to acid treatment, steam treatment and the like to elute the aluminum component, or it can be obtained by a hydrothermal synthesis method such as Am. Minera
l. 65, 1012 (1972), etc.
The one prepared with a high (silica / alumina) ratio is used. Alternatively, a material obtained by hydrothermal synthesis with a high (silica / alumina) ratio and further subjected to repeated acid treatment and steam treatment is used.

In the synthetic or natural mordenite, an alkali metal ion or a part of an alkali metal is obtained as an alkaline earth metal type, which is converted into a desired hydrogen ion type in the method of the present invention to convert dihydroxy-benzene. Used for dehydration condensation reaction.

[0011] Y- having a (silica / alumina) ratio of 40 or more
Zeolite has a relatively high (silica / alumina) ratio U
The SY-type zeolite is prepared by repeatedly performing acid treatment and steam treatment, or a SY-type zeolite synthesized by increasing the (silica / alumina) charging ratio to 40 or more during hydrothermal synthesis is used. US-Y in a flow of silicon tetrachloride
Type zeolite is treated at 400 to 600 ° C. (silica /
Higher (alumina) ratios can also be used in the method of the present invention. The high silica Y-type zeolite is also used in the dehydration condensation reaction of the present invention after ion exchange to the hydrogen ion type.

The dihydroxy-benzene used as a starting material in the process of the present invention is 1,4-dihydroxy-benzene (hydroquinone), 1,3-dihydroxy-benzene (resorcinol) or a mixture thereof.
When 1,4-dihydroxy-benzene is used as a starting material, the product obtained is 4,4'-dihydroxy-diphenyl ether. When 1,3-dihydroxy-benzene is used as a starting material, 3,3′-dihydroxydiphenyl ether is obtained. 1,3-dihydroxy-benzene and 1,
When a mixture of 4-dihydroxybenzene is used as a starting material, a mixture of 3,3′-form, 4,4′-form and 3,4′-dihydroxy-diphenyl ether is obtained.

To carry out the dehydration condensation reaction, the dihydroxy-benzene is reacted as it is or dissolved in an appropriate solvent. As the solvent, ethers such as diphenyl ether, dicyclohexyl ether, diethylene glycol dimethyl ether (diglyme) and triethylene glycol dimethyl ether (triglyme) are frequently used. When the (silica / alumina) ratio of high silica mordenite or high silica Y-type zeolite used as a catalyst is 90 or more, more preferably 150 or more, water can be used as a solvent because the hydrophobicity of the zeolite catalyst becomes strong. . Alternatively, a mixed solvent of water and alcohol, water and carboxylic acid, or water and cellosolves can be used. 1,3- or 1,4-dihydroxy-benzene is usually mixed with these solvents in an amount of 5 to 30% by weight for the reaction.

In the process of the present invention, in the case of a batch type reaction, a suspension bed type reactor is frequently used. In the case of a batch type reaction operation, usually 5 parts of the above reaction mixture is used during the dehydration condensation reaction.
The reaction is carried out by adding ２０20 wt% of high silica zeolite. The high silica zeolite to be added is often in the form of a powder or a microsphere in the case of a batch reaction. Microspherical zeolite catalysts are preferred for use in the method of the present invention because of their excellent operability when filtering or regenerating the catalyst. The particle diameter of the microspherical zeolite is often in the range of 30 to 500 nm.
It is preferable that the particle size distribution is in the above wide range. The catalyst having the above particle size distribution is obtained by slurrying powdery high silica zeolite together with a binder such as silica sol, alumina sol, clay or alumina cement, drying and forming the slurry with a spray drier, and further firing at 500 to 600 ° C. To manufacture. The amount of the binder component added is 10
The range of ５０50 wt% is frequently used.

The amount of the high silica zeolite catalyst used is 5 to 5 with respect to the above-mentioned reaction solution containing dihydroxy-benzene, for example, when the reaction is carried out batchwise.
The range of 20 wt% is frequently used. When the reaction is carried out in a flow system, a catalyst formed into tablets is used. A binder such as silica sol or alumina cement is mixed with the high silica zeolite powder, a small amount of water is added, and the mixture is kneaded to form a paste, followed by extrusion. The amount of the binder component added is often in the range of 10 to 30 wt%. The extrudate is dried at 100-150 ° C. and then
The catalyst is calcined at 0 ° C. to obtain a catalyst.

When the catalyst of the present invention is used repeatedly, tar or carbonaceous material may be deposited on the catalyst to reduce or deactivate the activity of the catalyst. The deactivated catalyst can be regenerated by washing with an organic solvent and then calcining at a high temperature in an air stream. In some cases, high-temperature firing may be performed directly without washing with an organic solvent. The high-temperature firing temperature is often in the range of 500 to 700 ° C.

When the dehydration-condensation reaction of the present invention is carried out by a batch reaction, a reaction temperature in the range of 150 to 300 ° C. is often used. The time required for the reaction ranges from 1 to 20 hours. In the case of a flow-through type reaction, a fixed-bed reactor is used. The contact time of the reaction mixture with the shaped high silica zeolite catalyst is 0.1 to 10 H in liquid hourly space velocity (LHSV).
The range of r- ¹ is frequently used. In the case of a flow reaction, the reaction temperature in the range of 200 to 400 ° C. is frequently used.

In the method of the present invention, the starting material, dihydroxy-benzenes, is a compound which is very easily oxidized by oxygen. Therefore, when carrying out the dehydration condensation reaction, oxygen or an atmosphere containing oxygen is not preferred. . Therefore, when performing the dehydration-condensation reaction, it is preferable to carry out the reaction in an atmosphere of an inert gas such as nitrogen or argon. More preferably, the dehydration condensation reaction is performed in a reducing atmosphere. As the reducing atmosphere, hydrogen or a mixed gas of hydrogen and nitrogen is often used. Prior to use, the solvents used in the method of the present invention are preferably used after bubbling with an inert gas or hydrogen gas and purging dissolved oxidizing gas such as oxygen. In the case of a suspension bed reaction, the catalyst is separated from the reaction mixture after completion of the reaction by a conventional method such as filtration or centrifugation, and then dihydroxy-diphenyl ether is isolated and obtained by means such as distillation under reduced pressure.

[0019]

The present invention will be specifically described below with reference to examples and comparative examples. Example 1 A slurry was prepared by mixing silica sol as a binder with a high silica mordenite powder having a (silica / alumina) ratio of 224. The weight ratio between the high silica mordenite and the silica component in the silica sol was 80:20, and the slurry concentration was adjusted to 20%. The obtained slurry was spray-dried to prepare a microspherical catalyst having a particle size of 30 to 150 nm. This was calcined at 500 ° C. to prepare a catalyst. The obtained catalyst was suspended in a 0.5 N hydrochloric acid aqueous solution, then sufficiently washed with deionized water, dried at 200 ° C. under a stream of nitrogen, and then used in the reaction.

1,4-dihydroxy-benzene 10 wt
% Was dissolved in diethylene glycol dimethyl ether. The diethylene glycol dimethyl ether used was used after blowing hydrogen gas to remove dissolved air. A 70 ml micro autoclave was charged with 40 ml of the above reaction solution and 2 g of microsphere catalyst of high silica mordenite. After replacing the gas phase of the autoclave with hydrogen gas, the mixture was stirred at 230 ° C. for 5 hours to carry out a dehydration condensation reaction. After cooling in the autoclave, the atmosphere was replaced with nitrogen, the catalyst was separated by filtration, and the reaction solution was analyzed by high performance liquid chromatography.
As a result, the conversion of 1,4-dihydroxy-benzene was 87% and the selectivity to 4,4′-dihydroxy-diphenyl ether was 82 mol%.

Example 2 A silica sol was mixed as a binder with a high silica Y-type zeolite powder having a (silica / alumina) ratio of 200, and water was further converted to prepare a slurry. The mixing ratio (weight) of zeolite and binder is 80:20, and the slurry concentration is 12
%. This slurry is spray-dried to a particle size of 35 to 150.
A microsphere of nm was prepared and calcined at 500 ° C. to prepare a catalyst. The obtained catalyst was suspended in a 0.5 N aqueous hydrochloric acid solution,
Then, it was washed with deionized water, dried at 200 ° C. in a nitrogen stream, and then used for the reaction.

In the same autoclave as in Example 1, 1,3
40 ml of a diphenyl ether solution mixed with 10% by weight of dihydroxy-benzene was charged. Before use, diphenyl ether was used after bubbling hydrogen gas to expel dissolved air. 1.5 g of a high silica Y-type zeolite catalyst was added to the reaction solution, and the autoclave gas phase was replaced with nitrogen to carry out a dehydration condensation reaction.

After stirring at 230 ° C. for 6 hours, the autoclave was cooled and the catalyst was separated by filtration from the reaction mixture. As a result of analyzing the reaction solution by high performance liquid chromatography, 1,3-
Conversion of dihydroxy-benzene 76%, selectivity to 3,3'-dihydroxy-diphenyl ether 81 mol
%.

Comparative Example 1 An ordinary synthetic mordenite powder having a (silica / alumina) ratio of 10 was granulated into fine spheres by spray drying in the same manner as in Example 1, and then converted to H-type to form a catalyst. Prepared.
1,4-Dihydroxybenzene was reacted under the same reaction conditions as in Example-1. After the catalyst was separated from the reaction solution, it was analyzed by high performance liquid chromatography. As a result, the conversion of 1,4-dihydroxybenzene was 21% and the selectivity of 4,4′-dihydroxy-diphenyl ether was 1%, which was substantially the same as the target compound. Has not been able to get.

Comparative Example 2 A normal US-Y type zeolite having a (silica / alumina) ratio of 6 was granulated into microspheres in the same manner as in Example 2, and ion-exchanged with an aqueous ammonium chloride solution to form H-type. A catalyst was prepared. Using this catalyst, 1,3-dihydroxy-benzene was reacted in the same manner as in Example-2. After separating the catalyst from the reaction solution, the reaction solution was analyzed by high performance liquid chromatography. As a result, the conversion of 1,3-dihydroxy-benzene was 25%, and the selectivity of 3,3′-dihydroxy-diphenyl ether was 1% or less. Yes, practically no object could be obtained.

Example 3 Using the same reaction conditions and equipment as in Example 1, the only solvent used was water from which dissolved air had been removed with hydrogen gas.
1,4-dihydroxy-benzene was reacted. As a result of analyzing the aqueous solution after the reaction, the conversion of 1,4-dihydroxybenzene was 38%, and the selectivity of 4,4′-dihydroxy-diphenyl ether was 87 mol%.

Example 4 Using the same reaction conditions and equipment as in Example 1, the catalyst used was a high silica mordenite having a (silica / alumina) ratio of 60, and 1,4-dihydroxy-benzene was reacted. I let it. As a result of analyzing the solution after the reaction, the conversion of 1,4-dihydroxy-benzene was 34%, and the selectivity of 4,4′-dihydroxy-diphenyl ether was 41 mol%.

[0028]

According to the method of the present invention, there is no problem as in the conventional method, and the use of mordenite of high silica or Y-type zeolite of high silica as a catalyst provides
The desired dihydroxy-diphenyl ether can be obtained from dihydroxy-benzene in a one-step reaction operation with a high yield. Further, the catalyst is separated from the reaction solution by means of filtration or the like, and then the desired product can be isolated and obtained with high purity by distillation under reduced pressure.

Claims (8)

[Claims] In producing dihydroxy-diphenyl ether by dehydration-condensation of dihydroxy-benzene, a high silica mordenite having a (silica / alumina) ratio of 40 or more or a Y-series having a (silica / alumina) ratio of 40 or more is used.
A method for producing dihydroxy-diphenyl ether, which comprises reacting in the presence of a zeolite catalyst. 2. The method according to claim 1, wherein the (silica / alumina) ratio of high silica mordenite or Y-type zeolite used as a catalyst is 90 or more. 3. The method according to claim 1, wherein the (silica / alumina) ratio of the high silica mordenite or the Y-type zeolite used as the catalyst is 150 or more. 4. The method according to claim 1, wherein the dihydroxy-benzene is 1,4-dihydroxy-benzene and the obtained dihydroxy-diphenyl ether is 4,4′-dihydroxy-diphenyl ether. 5. The process according to claim 1, wherein the dihydroxy-benzene is 1,3-dihydroxy-benzene and the obtained dihydroxy-diphenyl ether is 3,3′-dihydroxy-diphenyl ether. 6. The method according to claim 1, wherein the dehydration-condensation reaction is carried out using diphenyl ether, cyclohexyl ether, diglyme or triglyme as a solvent. 7. The method according to claim 1, wherein the dehydration condensation reaction is carried out using water or a solvent containing water. 8. The method according to claim 1, wherein the dehydration condensation reaction is carried out in an inert atmosphere or a reducing atmosphere.