JPH0625079A - Production of aromatic tetracarboxylic acid - Google Patents

Abstract

PURPOSE:To obtain a high-purity aromatic tetracarboxylic acid in high yield by using a specific catalyst in subjecting an aromatic tetra-alkyl compound to oxidation reaction with oxygen, etc., in an aliphatic monocarboxylic acid. CONSTITUTION:A compound of formula I (R<1> to R<4> are alkyl; X, Y and Z are each halogen, nitrile or nitro, and X and Z are 0-3; Y is 0-4), e.g. 1,3-bis(3,4- dimethylbenzoyl)benzene, etc., is made to react with oxygen or oxygen-containing gas in the presence of a catalyst composed of three components of (A) cobalt, (B) bromine or bromine and chlorine and (C) manganese, cesium, zirconium and/or nickel (e.g. cobalt bromide and manganese bromide). preferably at 150-200 deg.C to provide the objective compound of formula II. Furthermore, a catalyst having the weight ratio of the component C to the component A of 0.0001-100 is preferably used.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing an aromatic tetracarboxylic acid.

The aromatic tetracarboxylic acid produced according to the present invention is widely used as a raw material for various resins such as polyimide, polyamide, polyester, polyamideimide, and polyesterimide, a modifier, an epoxy resin curing agent, and a raw material for agricultural chemicals and dyes. Has various uses.

[0003]

2. Description of the Related Art Conventionally, as a method of producing an aromatic tetracarboxylic acid, a method of producing an aromatic tetramethyl compound obtained by Friedel-Crafts reaction of o-xylene and isophthalic acid chloride with nitric acid [JR
Pratt, DABlackwell, TLSt.Clair and NLAllphi
n, Polymer Preprints, 29 (1), 128 (1988).] are known.

However, in the reaction due to nitric acid oxidation, NOx gas and a large amount of waste water are generated, and therefore expensive treatment equipment is required as a measure against pollution. Furthermore, since it is a high-temperature reaction, side reactions such as nitration of aromatic nuclei occur and contaminate the product, which still has many problems as an industrial manufacturing technique.

Therefore, in producing the corresponding tetracarboxylic acid by oxidizing the aromatic tetraalkyl compound, a cheaper oxidizing agent is used, which is industrially advantageous in that it does not generate air or water pollutants or product contamination. It is hoped that a new method will be established.

[0006]

DISCLOSURE OF INVENTION Problems to be Solved by the Invention As a result of intensive studies to establish an inexpensive and pollution-free oxidation method as an alternative to the known nitric acid oxidation method, the present inventors have found that the aromatic tetraalkyl compound is aliphatic. In a monocarboxylic acid, in producing a corresponding aromatic tetracarboxylic acid by oxidizing with oxygen or an oxygen-containing gas, by using a catalyst composed of a specific heavy metal and a bromine compound or a bromine compound and a chlorine compound, It has been found that the target product can be obtained easily and in high yield.

The present invention has been completed based on such findings, and an object thereof is to provide an industrially advantageous method for efficiently producing an aromatic tetracarboxylic acid by using an inexpensive oxidizing agent.

[0008]

The method for producing an aromatic tetracarboxylic acid according to the present invention comprises the step of adding an aromatic tetraalkyl compound represented by the general formula (I) to an aliphatic monocarboxylic acid,
In producing the corresponding aromatic tetracarboxylic acid represented by the general formula (II) by oxidizing with oxygen or an oxygen-containing gas, at least (A) cobalt, (B) bromine or bromine and chlorine, (C) manganese, It is characterized by using a catalyst composed of three components of one or more heavy metals selected from cerium, zirconium and nickel.

[Wherein R ¹ , R ² , R ³ and R ⁴ are the same or different and represent an alkyl group, and X, Y and Z are the same or different and are a halogen group, a nitro group and a nitrile. Represents a group. X and Z represent 0 to 3, and Y represents 0 to 4. ]

[Wherein X, Y and Z are the same or different,
Represents a halogen group, a nitro group and a nitrile group. X and Z
Represents 0 to 3 and Y represents 0 to 4. ]

The aromatic tetraalkyl compound used as a raw material in the present invention can be generally synthesized by the Friedel-Crafts reaction of xylenes and phthalic acid dichlorides as described above, but is not limited to such a method.

The number of carbon atoms of the alkyl group of the aromatic tetraalkyl compound is, for example, 1 to 5, and a methyl group, an ethyl group and an isopropyl group are particularly preferable, and specific compounds include 1,3-bis (3,3). 4-dimethylbenzoyl)
Benzene, 1,3-bis (2,3-dimethylbenzoyl) benzene, 1,3-bis (3,4-diethylbenzoyl) benzene, 1,3-bis (3,4-diisopropylbenzoyl) benzene, 1,4 -Bis (3,4-dimethylbenzoyl) benzene, 1,4-bis (2,3-dimethylbenzoyl) benzene, 1,4-bis (3,4-)
Diisopropylbenzoyl) benzene, 1,3-bis (3,4-dimethyl-2-fluorobenzoyl) benzene, 1,3-bis (3,4-dimethylbenzoyl) -5
-Fluorobenzene, 1,4-bis (3,4-dimethyl-2-fluorobenzoyl) benzene, 1,4-bis (3,4-dimethylbenzoyl) -2,3,5,6-tetrafluorobenzene, 1 , 3-bis (3,4-dimethyl-2-nitrobenzoyl) benzene, 1,3-bis (3,4-dimethylbenzoyl) -2-nitrobenzene, 1,3-bis (3,4-dimethyl-2-) Cyanobenzoyl) benzene, 1,3-bis (3,4-dimethylbenzoyl) -5-cyanobenzene, 1,3-bis (3,3
4-dimethylbenzoyl) -2-cyanobenzene and the like are exemplified.

The catalyst used in the present invention comprises at least three components of (A) cobalt, (B) bromine or bromine and chlorine and (C) one or more heavy metals selected from manganese, cerium, zirconium and nickel. Composed.

(A) Cobalt is an elemental form, an oxide, a salt,
Although it may be in any form such as a complex, a salt which is at least partially dissolved in the reaction system, for example, cobalt acetate, cobalt bromide, cobalt naphthenate, cobalt hydroxide or the like is preferable.

The amount of cobalt used is 0.
01 to 10 g / l is suitable. If it is less than 0.01 g / l, a sufficient reaction rate cannot be obtained, and if it exceeds 10 g / l, the cost of the catalyst is increased and it becomes difficult to produce the desired product.

(B) As bromine, bromine molecules, acids, salts,
Either an oxyacid salt or an organic bromine compound can be used. Particularly, hydrogen bromide, ammonium bromide, manganese bromide, cerium bromide, cobalt bromide, tetrabromoethane, tribromoethane and the like are preferable. The same applies to chlorine.

The amount of bromine used is 0.1 to 1 in terms of bromine atom per atom of (A) cobalt and (C) heavy metal.
00 equivalents are suitable. If the amount is less than 0.1 equivalent, a sufficient reaction rate cannot be obtained, and if the amount is more than 100 equivalents, the contamination of the target substance with bromine and the burden of the catalyst cost increase, which is not preferable.

When bromine and chlorine are used in combination, the total amount thereof is suitably 0.1 to 100 equivalents in terms of atoms, and the ratio of chlorine to bromine is preferably 0.7 or less.

The (C) one or more heavy metals selected from manganese, cerium, zirconium and nickel may be in any form such as elemental form, oxide, salt and complex.

The amount of the heavy metal used is appropriately 0.0001 to 100, preferably 0.005 to 0.5, by weight with respect to the cobalt metal. 0.
If the addition amount is less than 0001, a large effect of promoting the reaction is not recognized, and if the addition amount exceeds 100, the catalyst cost is increased and it is economically disadvantageous.

As the catalyst system according to the present invention, specifically,
Cobalt bromide and manganese bromide, cobalt bromide and manganese acetate, cobalt acetate and manganese bromide, manganese acetate and cobalt acetate and ammonium bromide, cobalt acetate and manganese acetate and hydrogen bromide, cobalt bromide and cerium acetate,
Manganese bromide and cerium acetate, cobalt acetate and manganese acetate and cerium acetate and hydrogen bromide, cobalt bromide and zirconium acetate, cobalt acetate and nickel bromide, cobalt naphthenate and manganese naphthenate and tetrabromoethane, cobalt acetylacetonate And manganese acetylacetonate and hydrogen bromide, cobalt acetate and manganese acetate and cerium acetate and hydrogen bromide, and cobalt acetate and manganese acetate and hydrogen bromide and hydrogen chloride.

In this reaction method, an aliphatic monocarboxylic acid is used as a reaction solvent. It is relatively stable against oxidation and has 2 to 1 carbon atoms, which can be easily separated from the reaction product.
The saturated monocarboxylic acid of 0 is exemplified, and acetic acid is particularly preferable. The amount used varies depending on the type of raw material and reaction conditions, but is preferably 50 to 900 g / l.

The oxygen or oxygen-containing gas used as the oxidizing agent may be pure oxygen or industrial exhaust gas, but is not limited to these, and any gas containing oxygen may be used. Industrially, normal air is most suitable. is there.

The reaction temperature is in the range of 100 to 250 ° C, preferably 150 to 220 ° C. If the temperature is lower than 100 ° C, the reaction rate is slow, while if the temperature exceeds 250 ° C, the solvent or the product is decomposed, which is not preferable.

The reaction pressure is such that the total reaction pressure is 1 to 30 kg / cm ²
・ G, especially 3 to 20 kg / cm ² · G, and oxygen partial pressure 0.0
1 to 2.4 atm is preferable. Further, from the viewpoint of safety, it is desirable to operate so that the oxygen concentration in the exhaust gas is 8% by volume or less.

The method of the present invention is generally carried out as follows. That is, a reactor equipped with a stirrer equipped with a gas inlet and a gas outlet is charged with predetermined raw materials, a catalyst and a solvent, substituted or pressurized with a gas containing nitrogen or oxygen, and heated to a predetermined temperature. Stirring and gas blowing are not always necessary in this temperature rising process. The absorption of oxygen generally starts at 100 to 150 ° C, though it depends on the type of catalyst. When the absorption of oxygen begins, oxygen or oxygen-containing gas is introduced,
The reaction is performed while maintaining the oxygen partial pressure and temperature within a predetermined range. The exhaust gas is cooled and the condensate is returned to the reactor.

After the reaction for a predetermined time, the reaction product is cooled, the reaction product is taken out, and the target aromatic tetracarboxylic acid is crystallized as it is or by removing a part of the solvent by distillation, or after removing the solvent by distillation, another reaction is carried out. It is recrystallized from the above solvent and taken out.

A bubble column type reactor can be adopted in addition to the above-mentioned one equipped with a stirrer.

The reaction method is not limited to the batch reaction, and a continuous or semi-continuous method is also possible. Specifically, the raw material in the reactor,
The catalyst and the solvent are continuously supplied, the reaction is carried out while blowing oxygen or an oxygen-containing gas, or the reaction product is continuously withdrawn, or the catalyst and the solvent are charged in the reactor, and then only the raw materials, Alternatively, a method of charging the raw materials and the solvent and reacting for a certain period of time, then stopping the charging and continuing the reaction to complete the reaction is exemplified.

[0028]

The present invention will be described in detail below with reference to examples. The purity of the target aromatic tetracarboxylic acid is G
The yield was analyzed by LC and by HPLC.

Example 1 In a titanium autoclave equipped with a magnetic stirrer and having an internal volume of 500 ml equipped with a gas inlet and a gas outlet with a reflux condenser, 85.5 g of 1,3-bis (3,4-dimethylbenzoyl) benzene was added. cobalt bromide [CoBr ₂ · 6H ₂ O,
The same applies hereinafter] 2.80 g, manganese acetate [Mn (OCOC
_{H 3) 2 · 4H 2 O} , Similarly] 2.45 g and acetic acid 20
0 g was charged, the pressure was increased to 10 kg / cm ² · G with nitrogen, and the mixture was heated and stirred. When the temperature in the system started to introduce air at 150 ° C,
Refrigerating acetic acid vaporized by the cooler at the gas outlet and releasing exhaust gas, 170-180 ℃, pressure 20kg / c
The amount of introduced air was adjusted so that the oxygen concentration in the exhaust gas was in the range of 1 to 6% with m ² · G (oxygen partial pressure 0.1 to 0.8 a
tm). When the reaction was carried out for about 2 hours under these conditions, no absorption of oxygen was observed. At this point, the introduction of air was stopped and the reaction was continued for another 30 minutes. The reactor was cooled, the contents were taken out, and acetic acid and generated water were distilled off under reduced pressure to obtain 115 g of a reaction crude product (neutralization value: 452). As a result of the measurement, the target 4,4′-isophthaloyldiphthalic acid (hereinafter “I
It is abbreviated as "PDA". The purity of 9) was 91.6%, and the yield thereof was 93.7%.

Example 2 In the same reactor as in Example 1, 85.5 g of 1,3-bis (3,4-dimethylbenzoyl) benzene, 2.80 g of cobalt bromide, 0.02 g of manganese acetate and 200 ml of acetic acid.
g, charged with nitrogen to 10 kg / cm ² · G, and stirred with heating. Air begins to be introduced at a temperature in the system of 160 ° C, acetic acid evaporated by the cooler at the gas outlet is refluxed to discharge exhaust gas, and 175-185 ° C, pressure 20 kg / cm ²
・ The amount of introduced air was adjusted by G so that the oxygen concentration in the exhaust gas was in the range of 1 to 6% (oxygen partial pressure 0.1 to 0.8a
tm). When the reaction was performed for about 2.5 hours under these conditions, oxygen absorption was not observed. At this point, the introduction of air was stopped and the reaction was continued for another 30 minutes. The reactor was cooled, the contents were taken out, and acetic acid and generated water were distilled off under reduced pressure to obtain 115 g of a reaction crude product (neutralization value 471). Measurement result, I
The purity of PDA is 96.7%, and the yield is 98.6.
%Met.

The same reactor of 1,3-bis Example 3 Example 1 (3,4-dimethylbenzoyl) benzene 85.5 g, cobalt acetate _{[Co (OCOCH 3) 2 ·} 4H 2 O] 2.45g , Manganese acetate 0.015 g and ammonium bromide 2.50 g
And a reaction temperature of 17 g.
0-180 ℃, pressure 15kg / cm ² · G (oxygen partial pressure is 0.01
~ 0.6 atm) and react with IPDA for 3 hours.
Was manufactured. As a result of the measurement, the purity of the target product was 96.2%, and the yield thereof was 97.9%.

Example 4 As a catalyst, 3.26 g of cobalt bromide, manganese acetate of 0.
24 g, cerium acetate [Ce (OCOCH ₃ ) ₂ · H
₂ O, the same as below] 0.33 g and 47% hydrobromide water 1.
IPDA was prepared in the same manner as in Example 3 except that the catalyst consisting of 7 g was applied. As a result of the measurement, the purity of the target product is 9
The yield was 6.6% and the yield was 98.1%.

Example 5 1.10 g of cobalt bromide and cerium acetate of 0.
IPDA was prepared in the same manner as in Example 3, except that the catalyst consisting of 03 g and 1.0 g of sodium bromide was applied.
As a result of the measurement, the target product had a purity of 95.9% and a yield of 9
It was 7.3%.

Example 6 Cobalt naphthenate (Co: 6%) 7.50 as a catalyst
g, manganese naphthenate (Mn: 9%) 0.15 g and tetrabromoethane 9.70 g except that a catalyst was applied, IPDA was produced in the same manner as in Example 3. As a result of the measurement, the purity of the target product was 95.1%, and the yield was 96.
It was 8%.

Example 7 A catalyst consisting of 85.5 g of 1,4-bis (3,4-dimethylbenzoyl) benzene, 2.80 g of cobalt bromide and 2.45 g of manganese acetate and acetic acid was placed in the same reactor as in Example 1. Charge 200g, 175-185 ℃, 10kg / c
React for 3 hours under m ² · G conditions to obtain the desired 4,4 '
-Terephthaloyldiphthalic acid was obtained with a yield of 92.8%.

Example 8 In the same reactor as in Example 1, 85.5 g of 1,4-bis (3,4-dimethylbenzoyl) benzene, 2.40 g of cobalt acetate, 0.24 g of manganese acetate and 47% hydrogen bromide. Charge a catalyst consisting of 6.00 g of acid and 200 g of acetic acid,
The reaction was carried out under the conditions of 170 to 180 ° C. and 20 kg / cm ² · G for 3 hours to obtain the desired 4,4′-terephthaloyldiphthalic acid in a yield of 96.2%.

[0037]

By applying the catalyst system according to the present invention, the target aromatic tetracarboxylic acid can be obtained in high purity and high yield under industrially advantageous conditions.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akihiro Nishiuchi 13 No. 13 Yakura-cho, Fukumi-ku, Kyoto City, Kyoto Prefecture New Japan Rika Co., Ltd. (72) Inventor Hitoshi Yagi 13 No. 13 Yakura-cho, Fukumi-ku, Kyoto City, Kyoto Japan Rika Co., Ltd.

Claims (2)

[Claims] 1. An aromatic tetracarboxylic compound represented by the general formula (II) obtained by oxidizing an aromatic tetraalkyl compound represented by the general formula (I) with oxygen or an oxygen-containing gas in an aliphatic monocarboxylic acid. In producing the acid, at least (A) cobalt, (B) bromine or bromine and chlorine,
(C) A method for producing an aromatic tetracarboxylic acid, which comprises using a catalyst composed of three components of one or more heavy metals selected from manganese, cerium, zirconium and nickel. [Chemical 1] [Wherein R ¹ , R ² , R ³ and R ⁴ are the same or different,
It represents an alkyl group, and X, Y and Z are the same or different and represent a halogen group, a nitro group and a nitrile group. X and Z represent 0 to 3, and Y represents 0 to 4. ] [Chemical 2] [In the formula, X, Y and Z are the same or different and each represents a halogen group, a nitro group or a nitrile group. X and Z are 0-3
And Y represents 0 to 4. ] 2. The method for producing an aromatic tetracarboxylic acid according to claim 1, wherein a catalyst having a weight ratio of (C) heavy metal to (A) cobalt of 0.0001 to 100 is used.