JP3357151B2 - Method for producing azelaic acid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel process for producing azelaic acid.

[0002]

Azelaic acid is extremely useful as a starting material for polyesters, nylons, synthetic lubricating oils, plasticizers and the like.

[0003] Azelaic acid is industrially produced by ozone oxidation of oleic acid which is finally separated and obtained from beef tallow.

Although this method is interesting from the viewpoint of effectively utilizing natural resources, the process of separating oleic acid from beef tallow is complicated, requires an expensive ozone oxidation process, and the purification process of azelaic acid. Is complex,
It has disadvantages such as.

[0005] As a method for producing azelaic acid by purely chemically deriving tallow without using tallow as a starting material, 2,7- obtained by reacting butadiene and water in the presence of a palladium catalyst. Octadiene-1
-Isomerizing ol in the presence of a copper-based catalyst or a chromium-based catalyst, and hydroformylating the resulting 7-octen-1-al with a hydrogen / carbon monoxide mixed gas in the presence of a rhodium complex compound and trisubstituted phosphine. Azelaic acid, characterized in that oxygen oxidation of 1,9-nonandial in the liquid phase is carried out in the presence of at least one metal salt selected from a copper salt, an iron salt, a nickel salt, a cobalt salt and a manganese salt. A production method has been proposed (JP-A-58-140038).

This method uses 1,9
-Has the advantage that nonadials can be obtained from butadiene which can be obtained in large quantities and at a low cost through a simple process with a good yield, and the significance of industrialization is great in that 1,9-nonandial is used as a raw material.

[0007]

In the above-mentioned method, acetic acid, propionic acid, butyric acid, caproic acid,
Aliphatic monocarboxylic acids such as caprylic acid and methyl esters of aliphatic monocarboxylic acids are used.The use of these reaction solvents reduces the risk of explosion due to corrosion of the reactor and mixing of the reaction solvent with oxygen. Enthusiastic. In addition, this method has a problem that the peroxide concentration in the reaction solution is high.

Further, when azelaic acid is used as a raw material for polyester or nylon, it may be necessary to severely restrict the content of monocarboxylic acid in azelaic acid. According to the method described above, azelaic acid is purified by removing the majority of the reaction solvent from the reaction mixture after the oxidation reaction and treating the resulting residue with a dilute mineral acid aqueous solution to form an aqueous layer of the catalyst. It is performed by separating and acquiring azelaic acid by a conventional method after having been removed on the side,
It requires complicated processes such as distillation of the reaction solvent, use of dilute mineral acid aqueous solution, and separation of the catalyst.In addition, dedicated equipment and a huge amount of utilities for the recovery, recycling and wastewater treatment of the reaction solvent and catalyst And work is complicated.

It is an object of the present invention to solve these problems and to provide a process for industrially and advantageously producing azelaic acid from 1,9-nonandial.

[0010]

According to the present invention, it has been found that the above-mentioned object is achieved by oxygen-oxidizing 1,9-nonandial in an aqueous solvent.

By subjecting the reaction mixture after the oxidation reaction to a crystallization operation, high-purity azelaic acid can be obtained.

Oxygen oxidation of 1,9-nonandial according to the present invention is carried out by contacting 1,9-nonandial with oxygen gas or oxygen-containing gas in an aqueous solution. As the oxygen-containing gas, air, a mixed gas of nitrogen and oxygen having an arbitrary ratio, or a mixed gas of these and helium gas, argon gas, carbon dioxide gas, or the like is used.

The reaction temperature is 50 to 150 ° C., especially 8
Temperatures in the range of 0 to 120C are preferred.

The reaction according to the present invention can be carried out in the presence or absence of an oxidation catalyst. There is no particular limitation on the use of an oxidation catalyst, but it is preferable to use it. In this case, the oxidation catalyst that can be used may be a generally known catalyst without any particular limitation. As an example of the oxidation catalyst, first, a catalyst in which a metal is supported on a carrier can be used. Specifically, examples of the metal include platinum, palladium, ruthenium, and the like. The metal may be supported alone on the carrier, or may be supported on the carrier in combination of two or more kinds. Examples of the carrier include activated carbon, alumina, calcium carbonate, barium carbonate and the like. Further, the catalyst in which these metals are supported on a carrier,
Those which are partially modified with other metal components selected from tin, lead, bismuth, selenium, tellurium, cerium and the like can also be used.

[0015] These catalysts are commercially produced and are readily available.

Secondly, metal salts such as copper salts, iron salts, nickel salts, cobalt salts and manganese salts can be mentioned. Specifically, cuprous halide, cupric halide,
Cuprous carboxylate, cupric carboxylate, cuprous sulfate, cupric sulfate, ferrous halide, ferric halide, ferrous carboxylate, ferric carboxylate, ferric sulfate , Nickel carboxylate, nickel sulfate, nickel halide, cobaltous carboxylate, cobaltous sulfate, cobaltous nitrate, manganese carboxylate, manganese sulfate and the like.

In consideration of the solubility of these metal salts in the reaction mixture, the corrosiveness to the reaction apparatus, the availability, and the like, the metal salt used is particularly preferably an aliphatic monocarboxylate. The metal salts as catalysts may be used alone or in combination of two or more. The catalytic metal salt is usually used at a concentration of 0.01 to 10 milligram atoms in terms of metal per liter of the reaction mixture.

Further, bromides such as hydrogen bromide, calcium bromide, lithium bromide, sodium bromide, potassium bromide and ammonium bromide can be used in combination as a co-catalyst.

[0019] According 1,9 oxygen oxidation of Nonanjiaru water to how the presence or absence of a normal prior Symbol of the metal salt catalyst and / or metal-supported catalysts as a solvent of the present invention, oxygen gas or oxygen-containing Gas, and 1,9-
It is carried out by continuously or intermittently feeding nonangial.

In this case, as the reactor, a general-purpose stirring type reactor, bubble column type reactor,
A perforated plate reactor is used. Since the optimum range of the reaction pressure varies depending on the oxygen concentration in the oxygen-containing gas, the reaction temperature, the catalyst concentration, and the like, it cannot be uniquely defined, but is usually selected from the range of 1 to 30 atm (absolute pressure). .

The present oxidation reaction can be carried out in a continuous mode or a batch mode.

When a metal salt catalyst is used, azelaic acid can be separated and obtained from the reaction mixture after the reaction by crystallization. The metal salt catalyst has migrated to the water layer side, and can be recycled as it is.

When a metal-supported catalyst is used, azelaic acid can be separated by crystallization from the reaction mixture after the reaction and once filtered while hot.

In any case, it is preferable to drive the conversion of 1,9-nonandial at a relatively low temperature to about 90 to 98%, and then drive the reaction at a relatively high temperature in another reactor.

[0025] has the sufficiently high purity crude azelaic acid obtained as these themselves can be purified by recrystallization from aqueous solution if necessary.

[0026]

EXAMPLES The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1 A thermometer, a pressure gauge, an electromagnetic stirrer, a raw material feed port, a water feed port, an air inlet, and a heating device with an accessory 100
Contents 3 equipped with a gas-liquid separation tube (reaction liquid outlet)
150 ml of water in a pressure-resistant reactor of 00 ml and 5% in activated carbon
Supported platinum (made by Degussa Japan Co., Ltd.)
0.5 g was added, and the mixture was heated while maintaining the pressure at 5 atm (absolute pressure) with air. The microfeeder connected to the raw material feed port was charged with 150 ml of nitrogen-substituted 1,9-nonandial, and the microfeeder connected to the water feed port was charged with 250 ml of distilled water.
When the temperature in the reactor became constant at 90 ° C., the content was stirred at a rotation speed of 1000 rpm, and air was introduced at a rate of 10 liter / hr, and 5 ml / hr was fed from the raw material feed port. 1,9-nonandial at a rate of 10 ml / hr and distilled water at a rate of 10 ml / hr from the water feed port were continuously added over a period of 20 hours so that the liquid volume in the reactor was maintained at 150 ml.
Mix the reaction solution 15m from the gas-liquid separation tube heated to 0 ° C constant.
The oxidation reaction was performed while extracting at a rate of 1 / hr.

Immediately after the start of the addition of 1,9-nonandial, the conversion of 1,9-nonandial was measured by gas chromatography every three hours.
That was all.

The reaction mixture thus obtained is mixed with hot water for 25 minutes.
ml at a feed rate of ml / hr and filtered while hot.
When cooled to room temperature, white crystals were precipitated and were separated by filtration. A total of 93 g of white crystals were collected. Various analyzes confirmed that the white crystals were azelaic acid. The acquisition rate of azelaic acid after recrystallization was 82% based on the mole of 1,9-nonandial added.

Example 2 70 ml of water was placed in a 100 ml pressure-resistant reactor equipped with a thermometer, a pressure gauge, an electromagnetic stirrer, a raw material feed port, an air inlet and an outgassing line, 5% palladium and 5% 5% on activated carbon. 0.6 g of a catalyst supporting Bismuth (manufactured by Degussa Japan Co., Ltd.) was added, and 10 atm of air was added.
(Absolute pressure) while heating. The microfeeder connected to the raw material feed port was charged with 15 ml of 1,9-nonandial which had been purged with nitrogen in advance. When the temperature in the reactor became constant at 95 ° C., the contents were stirred at a rotation speed of 700 rpm, and the gas was fed at a rate of 2 ml / hr from the raw material feed port while discharging the gas at a rate of 10 liter / hr. The oxidation reaction was carried out by continuously adding 1,9-nonandial at a rate over a period of 5 hours.

After the completion of the addition of 1,9-nonandial,
An additional 6 at 95 ° C and 10 atmospheres of air (absolute pressure).
The mixture was stirred for a period of time to complete the oxidation reaction.

After the reaction mixture thus obtained was filtered while hot, the obtained filtrate was cooled to room temperature, and white crystals were deposited. A total of 9.5 g of white crystals were collected. Various analyzes confirmed that the white crystals were azelaic acid. The acquisition rate of azelaic acid after recrystallization was 83% based on the mole of 1,9-nonandial added.

Comparative Example 1 Acetic acid (60 ml) and copper acetate (42 mg) were added to a 200 ml four-necked flask equipped with a thermometer, a magnetic stirrer, a reflux condenser, a raw material feed port and an oxygen inlet, and the contents were stirred. While heating, the copper acetate was completely dissolved. The microfeeder connected to the raw material feed port was charged with 100 ml of a 2 mol / liter 1,9-nonandial acetic acid solution which had been purged with nitrogen in advance. When the temperature in the reactor became constant at 65 ° C., the content was reduced to 800 rpm.
Stirring at a rotational speed of 10 liters, and oxygen gas at 10 l / h
20 ml from the material feed port while introducing at a rate of r
The oxidation reaction was carried out by continuously adding a solution of 1,9-nonandial in acetic acid over 3 hours at a feed rate of / hr. Immediately after the completion of the addition of 1,9-nonandial, the conversion of 1,9-nonandial was measured by gas chromatography to be 93%.

After the completion of the addition of 1,9-nonandial, the internal temperature was raised to 90 ° C., and stirring was further continued for 1 hour. One hour later, gas chromatography analysis showed that only a trace of unreacted 1,9-nonandial remained in the reaction mixture. Acetic acid was distilled off from the reaction mixture thus obtained using a rotary evaporator. The residue was washed with 100 ml of a 1% by weight aqueous hydrochloric acid solution and then dissolved in 380 ml of boiling water with stirring.
When cooled to room temperature, white crystals were precipitated and were separated by filtration. A total of 18 g of white crystals were collected. Various analyzes confirmed that the white crystals were azelaic acid. The acquisition rate of azelaic acid after recrystallization was 1,9
-80% on a molar basis of nonangial.

[0035]

According to the present invention, 1,9-nonane di A over <br/> Le by oxygen oxidation in water solvent, it is possible to industrially advantageously produce azelaic acid. 1,9-nonane di are used as a reaction raw material can be obtained in good yield through a simple process from a large amount and cheaply available butadiene. By subjecting the reaction mixture after the oxidation reaction to a crystallization operation, high-purity azelaic acid can be obtained.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-58-140038 (JP, A) JP-A-55-89241 (JP, A) JP-A-4-352743 (JP, A) JP-A-60-1985 193944 (JP, A) JP-A-48-36119 (JP, A) JP-A-49-54313 (JP, A) JP-A-62-269746 (JP, A) JP-A-62-269749 (JP, A) Japanese Patent Publication No. 40-24176 (JP, B1) Japanese Patent Publication No. 37-14071 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) C07C 55/18 C07C 51/235

Claims (1)

(57) [Claims] 1. A method for producing azelaic acid, wherein 1,9-nonandial is subjected to oxygen oxidation in an aqueous solvent.