JPH06192867A - Production of quaternary ammonium hydroxide aqueous solution - Google Patents

Abstract

PURPOSE:To inexpensively produce a quaternary ammonium hydroxide aq. solution by electrolyzing a quaternary ammonium inorganic acid salt synthesized by allowing a quaternary ammonium organic acid salt to react with hydrogen peroxide. CONSTITUTION:The quaternary ammonium inorganic acid salt is synthesized by allowing the quaternary ammonium organic acid salt to react with hydrogen peroxide and the quaternary ammonium hydroxide is obtained by electrolyzing the quaternary inorganic acid salt. Then, the high purity quaternary ammonium hydroxide aq. solution used for developing a positive resist or cleaning the substrate or the like in a producing process of LSI or CD is inexpensively produced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-purity quaternary ammonium hydroxide aqueous solution used for a positive resist developing solution, a substrate cleaning solution, or the like in a manufacturing process of LSI or LCD, or a polycarbonate resin. The present invention relates to a method for producing a quaternary ammonium hydroxide aqueous solution used for producing a polymerization catalyst, a zeolite catalyst and the like.

[0002]

2. Description of the Related Art Aqueous quaternary ammonium hydroxide solution has a wide range of uses and is currently produced in large quantities. Particularly, in recent years, inexpensive and highly pure aqueous quaternary ammonium hydroxide solution has been demanded.

Conventionally, the following method has been used to produce quaternary ammonium hydroxide. 1) A method for producing a quaternary ammonium hydroxide by reacting a trialkylamine with an alkyl halide to synthesize a quaternary ammonium halide, and electrolyzing the quaternary ammonium halide.

2) A trialkylamine is reacted with an organic carboxylic acid ester to synthesize a quaternary ammonium organic carboxylic acid salt, and the quaternary ammonium organic carboxylic acid salt is electrolyzed to produce a quaternary ammonium hydroxide. how to. (JP-A-60-100690)

3) A method for producing a quaternary ammonium hydroxide by reacting a trialkylamine with a carbonic acid dialkyl ester to synthesize a quaternary ammonium inorganic acid salt and electrolyzing the quaternary ammonium inorganic acid salt. .

In the above method (1), harmful and corrosive halogen ions and halogen gas are produced at a high concentration in the anode during the electrolysis process, causing troubles such as corrosion of the anode itself or the material of the apparatus. . Further, in the case of producing a high-purity quaternary ammonium hydroxide aqueous solution, during the electrolysis, halide ions migrate to the cathode side through the ion exchange membrane, or due to causes such as an increase in impurities due to corrosion, It has the drawback of reducing the purity.

In the above method (2), a large amount of electricity is required to generate corrosive organic acid ions in the electrolysis step, corrode the anode itself, and electrolytically oxidize the formate ions to harmless carbon dioxide gas. There are problems such as In the case of producing a high-purity quaternary ammonium hydroxide aqueous solution, during electrolysis, organic acid ions pass through the ion exchange membrane and migrate to the cathode side, or the purity increases due to the increase of impurities due to corrosion. It has the drawback of causing a decrease.

In the production method (3), a carbonic acid dialkyl ester is used as a raw material, but the carbonic acid dialkyl ester is expensive, and is not suitable for manufacturing an inexpensive quaternary ammonium hydroxide aqueous solution.

Further, since the carbonic acid dialkyl ester is produced from phosgene and alcohol, there is a possibility that a chlorine compound may be mixed in the carbonic acid dialkyl ester, which is preferable for producing a high-purity quaternary ammonium hydroxide aqueous solution. Absent. As described above, the conventional manufacturing methods have many problems, and none of them are sufficient manufacturing methods, and a method for manufacturing an inexpensive and highly pure quaternary ammonium hydroxide aqueous solution is desired. There is.

[0010]

DISCLOSURE OF THE INVENTION The present invention solves various problems of the above-mentioned conventional methods and provides an inexpensive and highly pure aqueous quaternary ammonium hydroxide solution. is there.

[0011]

Means for Solving the Problems The inventors of the present invention have made earnest studies to solve various problems in the above-mentioned prior art, and reacted a quaternary ammonium organic acid salt with hydrogen peroxide to give a quaternary ammonium organic acid salt. To find a novel method for producing quaternary ammonium hydroxide by synthesizing a quaternary ammonium inorganic acid salt and electrolyzing the obtained quaternary ammonium inorganic acid salt to form a quaternary ammonium hydroxide, to form the present invention. I arrived.

More specifically, an aqueous solution of a quaternary ammonium organic acid is added in the presence of a platinum group catalyst of palladium, platinum, ruthenium, rhodium or iridium at 10 to 100 ° C.
To react with hydrogen peroxide to synthesize a quaternary ammonium inorganic acid salt, and the aqueous solution of the obtained quaternary ammonium inorganic acid salt is electrolyzed using an electrolytic cell using an ion exchange membrane as a diaphragm to The present invention relates to a novel method for producing a quaternary ammonium hydroxide aqueous solution for obtaining quaternary ammonium.

The quaternary ammonium organic acid salt in the present invention is represented by the following formula (1).

[0014] (However, R _{1 to} R ₄ in the formula may be the same or different and each represents a C _{1 to} C ₃ alkyl group, and X represents an organic acid having a carboxyl group.)

The compound represented by the above general formula is specifically tetramethylammonium formate, tetramethylammonium acetate, tetramethylammonium propionate, tetramethylammonium oxalate, tetramethylammonium malonate, Tetramethylammonium maleate, tetramethylammonium succinate, tetramethylammonium fumarate, tetramethylammonium acrylate, tetramethylammonium methacrylate, tetramethylammonium benzoate, tetraethylammonium formate, tetraethylammonium Acetate, tetraethylammonium propionate, tetraethylammonium oxalate, trimethylethylammonium formate, trimethylethylammonium acetate, Tiger propyl ammonium formate, tetrapropylammonium acetate, and the like. Of these, tetramethylammonium formate is preferred. In addition, the above quaternary ammonium organic acid salt,
It can be easily synthesized from a trialkylamine and an organic acid ester.

The platinum group catalyst used in the present invention includes palladium, platinum, ruthenium, rhodium, iridium metal, activated carbon, carbon material such as carbon fiber and activated carbon fiber, silica,
A catalyst supported on a carrier such as alumina, silica alumina, or zeolite is used. Among these catalysts, a catalyst in which palladium is supported on a carbon material is preferable. The platinum group catalyst of the present invention is preferably a catalyst supporting palladium, platinum, ruthenium, rhodium, or iridium metal in an amount of 0.01 to 20% by weight, preferably 0.05 to 10% by weight, based on the above carrier.

The reaction of the quaternary ammonium organic acid salt with hydrogen peroxide in the present invention is carried out in the presence of the platinum group catalyst at a reaction temperature of 10 to 100 ° C., preferably 20 to 80 ° C. Further, the reaction of the quaternary ammonium organic acid salt with hydrogen peroxide in the present invention is sufficient under normal pressure, and there is no problem even if it is carried out under pressure. Further, the molar ratio of the quaternary ammonium organic acid salt to hydrogen peroxide in the present invention is 1 or more, and is appropriately selected in consideration of the kind of the quaternary ammonium organic acid salt used, the kind of the catalyst, and the reaction conditions. However, it is generally in the range of 1 to 20, preferably 1 to 1.
It is performed in the range of 0. The reaction between the quaternary ammonium organic acid salt and hydrogen peroxide can be carried out by any of a batch system, a semi-batch system and a continuous system.

The electrolysis of the quaternary ammonium inorganic acid salt obtained by the reaction of the quaternary ammonium organic acid salt with hydrogen peroxide in the present invention is usually divided into an anode and a cathode by a cation exchange membrane. Although an electrolysis cell is used, an electrolysis cell divided into an anode chamber, a cathode chamber and one or more intermediate chambers by two or more cation exchange membranes can be used.

As the cation exchange membrane used in the present invention, a corrosion resistant fluororesin-based one having a cation exchange group such as a sulfone group or a carboxylic acid group is preferably used. Styrene having the above-mentioned exchange group
Divinylbenzene copolymer type may also be used.

As the catalyst used in the present invention, an electrode used for this type of electrolysis such as a high-purity carbon electrode and a titanium electrode coated with a platinum group oxide such as platinum or iridium is used. As the cathode used in the present invention, an electrode used in this type of electrolysis, such as stainless steel or nickel, is used. These anodes and cathodes are plate-shaped,
Any shape such as a mesh shape and a perforated plate shape may be used.

In the present invention, electrolysis in the electrolytic cell is carried out by applying a DC voltage, the current density of which is 1 to 100 A / dm ² , preferably 3 to 50 A / d.
m ² . The temperature during electrolysis is preferably in the range of 10 to 50 ° C.

The electrolysis in the present invention can be carried out by either a batch system or a continuous system. At this time, the concentration of the quaternary ammonium inorganic acid salt as a raw material supplied to the anode chamber is 1 to 60% by weight.
It is preferably set to 3 to 40% by weight. Water is usually supplied to the cathode chamber, but at the start of operation, water alone has a low electric conductivity and electrolysis is difficult to occur. Therefore, a small amount of quaternary ammonium hydroxide, which is a target substance, such as 0.
It is desirable to use a solution added with 01 to 5% by weight. Further, it is desirable to perform the electrolysis in an atmosphere of an inert gas such as nitrogen or argon.

Examples of the present invention will be shown below. Example 1 A catalyst having 0.5% by weight of palladium supported on activated carbon having a particle size of 1 to 2 mm was charged in a reactor having an inner diameter of 40 mm in an amount of 1 liter. An aqueous solution containing 20.6% by weight of tetramethylammonium formate and 7.5% by weight of hydrogen peroxide was fed to the reactor heated to 60 ° C. at a flow rate of 1000 g / hour under normal pressure. After the reaction, the concentration of tetramethylammonium inorganic acid salt was 23.3% by weight, the concentration of tetramethylammonium formate was 0.02% by weight, and hydrogen peroxide was not detected. Next, as a cation exchange membrane, Nafi
on324 (a fluorine-based cation exchange membrane manufactured by DuPont) is used, the electrolytic cell is divided into an anode chamber and a cathode chamber, a titanium electrode coated with platinum is used for the anode, and a nickel electrode is used for the cathode. Then, a 23.3 wt% aqueous solution of the above tetramethylammonium inorganic acid salt was circulated in the anode chamber. In the cathode chamber, 0.5 wt% tetramethylammonium hydroxide aqueous solution was circulated, a direct current of 10 A / dm ² was applied, and electrolysis was performed at a temperature of 35 ° C. Electrolysis voltage is 5-6
V, average current efficiency is 88%, 16.2% by weight in the cathode chamber
An aqueous solution of tetramethylammonium hydroxide was obtained. The concentration of tetramethylammonium formate in the cathode chamber after electrolysis was 0.003% by weight.

Example 2 The same reactor used in Example 1 was heated to 40 ° C. and an aqueous solution containing 28.8% by weight of tramethylammonium formate and 9.0% by weight of hydrogen peroxide was added under normal pressure. 500 g /
Feed at a flow rate of time. After the reaction, the concentration of the tetramethylammonium inorganic acid salt was 32.5% by weight, the concentration of tetramethylammonium formate was 0.05% by weight, and hydrogen peroxide was not detected. Next, Example 1 was repeated except that a titanium electrode coated with iridium oxide was used as an anode.
Using the same electrolytic cell as above, a 32.5 wt% aqueous solution of the above tetramethylammonium inorganic acid salt was circulated in the anode chamber. A 0.3% by weight tetramethylammonium hydroxide aqueous solution was circulated in the cathode chamber, a direct current of 15 A / dm ² was applied, and electrolysis was performed at a temperature of 40 ° C. Electrolysis voltage is 7 ~
9V, average current efficiency is 84%, 20.7 in cathode chamber
A wt% aqueous solution of tetramethylammonium hydroxide was obtained. The concentration of tetramethylammonium formate in the cathode chamber after electrolysis was 0.007% by weight.

Example 3 1 liter of a catalyst prepared by loading 1.0% by weight of palladium on silica having a particle diameter of 1 to 2 mm was charged in the reactor used in Example 1. An aqueous solution containing 8.3% by weight of tetramethylammonium formate and 6.0% by weight of hydrogen peroxide was fed to the reactor heated at 50 ° C. under normal pressure at a flow rate of 300 g / hour. After the reaction, the concentration of the tetramethylammonium inorganic acid salt was 9.1% by weight, the concentration of the tetramethylammonium formate was 0.21% by weight, and hydrogen peroxide was not detected. The same electrolytic cell used in Example 2 was used, and a 9.1 wt% aqueous solution of the above tetramethylammonium inorganic acid salt was circulated in the anode chamber. 0.5 wt% tetramethylammonium hydroxide aqueous solution was circulated in the cathode chamber, a direct current of 20 A / dm ² was applied, and electrolysis was performed at a temperature of 40 ° C. The electrolysis voltage was 8 to 12 V, the average current efficiency was 81%, and a 7.8 wt% tetramethylammonium hydroxide aqueous solution was obtained in the cathode chamber. In addition, the amount of tetramethylammonium formate in the cathode chamber after electrolysis is 0.01
The concentration was 2% by weight.

[0026]

According to the method of the present invention, an LSI or LC
It is possible to inexpensively manufacture a high-purity quaternary ammonium hydroxide aqueous solution used as a developing solution for a positive resist in a manufacturing process of D, a cleaning solution for a substrate or the like.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masahiro Miyake, Niigata City, Niigata City, Tayuhama, Niiwari 182, Niigata Research Center Mitsubishi Gas Chemical Co., Ltd.

Claims (2)

[Claims] 1. A general formula (However, R _{1 to} R ₄ in the formula may be the same or different and each represents a C _{1 to} C ₃ alkyl group, and X represents an organic acid having a carboxyl group.) Characterizing that a quaternary ammonium organic acid salt is reacted with hydrogen peroxide to synthesize a quaternary ammonium inorganic acid salt, and the quaternary ammonium inorganic acid salt is electrolyzed to produce a quaternary ammonium hydroxide. And a method for producing a quaternary ammonium hydroxide aqueous solution. 2. A platinum group-based catalyst is used when the quaternary ammonium organic acid salt is reacted with hydrogen peroxide to synthesize a quaternary ammonium inorganic acid salt. Item 1. A method for producing a quaternary ammonium hydroxide aqueous solution according to item 1.