JPH09263403A - Production of hydrazine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To synthesize ketazine at a high rate of reaction in a high yield with high selectivity and to profitably obtain hydrazine by synthesizing ketazine in the presence of CO2 when hydrazine is produced using an arsenic compd. as a catalyst. SOLUTION: When ketone is allowed to react with ammonia and H2 O2 in the presence of a working soln. contg. an org. arsenic compd. to synthesize ketazine and this ketazine is hydrolyzed to produce hydrazine, ketazine is synthesized in the presence of CO2 . The amt. (mol) of this CO2 is preferably 0.0001-10 times that of the H2 O2 . The org. arsenic compd. is, e.g. methylarsonic acid, ethylarsonic acid or diethylarsinic acid. The ketone is preferably acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an industrial process for producing hydrazine.

[0002]

2. Description of the Related Art As a method for producing hydrazine, there is a method of oxidizing ammonia with an oxidizing agent such as hydrogen peroxide in the presence of a ketone to synthesize ketazine, and hydrolyzing the ketazine. In the method using hydrogen peroxide, azine is synthesized according to the following reaction, and the azine is hydrolyzed to produce hydrazine. The first stage azine synthesis is carried out in the presence of a single catalyst or catalyst mixture (Chemical Formula 1). The catalyst is used in the form of a working solution. Adin
After the reaction is complete, it is separated from the working solution. The working solution is regenerated and recycled to the first stage. In the second stage of this reaction, the azine is hydrolyzed to hydrazine and the ketone is recovered and recycled to the first stage (Formula 2).

[0003]

[Chemical formula 1]

[0004]

[Chemical formula 2]

As a method for synthesizing ketazine, Japanese Patent Publication No.
-41509, general formula RR'As (= O) X
Alternatively, it is described that by using an organic arsenic compound catalyst represented by R ″ As (═O) XY, ketazine can be synthesized from ketone, ammonia and hydrogen peroxide with high selectivity and high yield. JP-A-54-90108 describes that an azine can be produced by reacting an organic carbonyl compound with hydrogen peroxide and ammonium carbonate and / or ammonium bicarbonate. , Carbon dioxide gas and ammonia may be added to the reaction liquid to generate it, which indicates that carbon dioxide serves as a catalyst.
However, this method is not sufficient in terms of reaction rate and selectivity, and is unsatisfactory for its industrial viability.
Further, in Japanese Patent Publication No. 7-80829, in a method of synthesizing azine by reacting ammonia, hydrogen peroxide and a carbonyl compound in a working solution containing a catalyst, carbon dioxide concentration in the reaction solution is completely removed, A method of reacting in a system without the presence of carbon dioxide is disclosed.

[0006]

DISCLOSURE OF INVENTION Problems to be Solved by the Invention As a result of intensive studies conducted by the present inventors to obtain hydrazine efficiently and in high yield, carbon dioxide coexists in the process for producing hydrazine using an arsenic compound as a catalyst. It was thus found that the rate of formation of ketazine was increased without lowering the selectivity, and a higher yield of ketazine was achieved in a shorter reaction time than in the absence of carbon dioxide.

[0007]

Means for Solving the Problems That is, according to the present invention, a ketone, ammonia and hydrogen peroxide are reacted in the presence of a working solution containing an organic arsenic compound to produce ketazine, and the ketazine is hydrolyzed, A method for producing hydrazine, which comprises producing ketazine in the presence of carbon dioxide.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The ketone used in the present invention is represented by the general formula R ₁ R ₂ C═O. Where R
₁ , R ₂ is an alkyl group containing 1 to 12 carbon atoms,
Represents a branched alkyl group or cycloalkyl group containing 3 to 12 carbon atoms, an aromatic group containing 6 to 12 carbon atoms or a straight chain or branched alkylene group containing 3 to 12 carbon atoms, groups, halogen, NO ₂ group, hydroxy group, may be substituted by an alkoxy group or a carboxylic acid ester. R ₁ and R ₂ may be the same or different from each other. Specifically, acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone are preferably used. The hydrogen peroxide used in the present invention may be a commercially available 30 to 90% by weight, preferably 60 to 90% by weight, aqueous H ₂ O ₂ solution. As the ammonia, gaseous ammonia or an aqueous ammonia solution is used. Each reaction product can be used in a stoichiometric amount, but 0.2 to 5 mol of methyl ethyl ketone, preferably 1.
5 to 4 mol, and ammonia can be used in an amount of 0.1 to 10 mol, preferably 1.5 to 4 mol.

The catalyst used in the present invention is represented by the general formula (1) RR'As (= O) X or R "As (= O) XY (1) (wherein R , R ′, R ″ are alkyl groups, aralkyl groups or aryl groups, X, Y are alkyl groups, aralkyl groups,
An organic arsenic compound represented by an aryl group, a halogen, a hydroxyl group or an alkoxy group), particularly preferably RR′As (═O) OH and R ″ As (═O).
Organic arsinic acid and organic arsonic acid represented by (OH) ₂ . Specifically, for example, methylarsonic acid, ethylarsonic acid, phenylarsonic acid, (o, m and p-)
Methylphenylarsonic acid, (o, m and p-) methoxyphenylarsonic acid, (o, m and p-) carboxyphenylarsonic acid, (o, m and p-) chlorophenylarsonic acid, (o, m and p) -) Nitrophenylarsonic acid, cacodylic acid, diethylarsinic acid, diphenylarsinic acid and the like can be mentioned. The catalyst concentration is determined depending on the reaction conditions and economical conditions, but is generally 0.01 to 10 times the molar amount of hydrogen peroxide used, preferably 0.1 to 1
It is preferably 0 times the mole.

The catalyst can be diluted with a solvent inert to the reaction and used as a working solution. The working solution may be an aqueous solution, an alcohol solution, or a mixed solution of water and alcohol. Examples of the alcohol in this case include methanol, ethanol, ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol and 1,5-pentanediol. The amount of working solution is 0.1 to 10 k with respect to 1 mol of hydrogen peroxide.
g. In addition, ethylenediaminetetraacetic acid disodium salt or 8
-Adding a chelating agent such as hydroxyquinoline is also one of the preferred embodiments of the present invention.

The contact of the reactant containing hydrogen peroxide, ammonia and ketone with the working solution can be carried out by any method. Preferably, it is carried out by dropping the aqueous hydrogen peroxide solution and the ketone into a homogeneous medium or a medium capable of solubilizing each reactant sufficiently to obtain ketazine. The above reaction can be carried out in a very wide range of temperatures, but 30 to 70 ° C is preferable. Further, although this reaction can be carried out at any pressure, it is easier to operate at atmospheric pressure. Each reactant can be added to the working fluid simultaneously or separately in any order. As the reaction device, a stirring and mixing tank or a fluidized tank in which the contact between each reactant and the working liquid is favorably performed is preferable.

In the present invention, the presence of carbon dioxide in the reaction system includes the presence of not only carbon dioxide but also carbonate ions or carbonates in the reaction system. Therefore, as a method of introducing carbon dioxide into the reaction system, not only a method of directly introducing carbon dioxide into the ketazine synthesis reaction apparatus but also a method of introducing carbonate can be used. Even if introduced as carbon dioxide, it may react with ammonia in the reaction device to form an ammonium salt such as ammonium carbonate. The carbonate may be a by-product of the reaction system. As the carbonate introduced into the reaction apparatus, ammonium salts such as ammonium carbonate, ammonium bicarbonate and ammonium carbamate can be particularly preferably used. In the case of a heavy metal carbonate, its use is not preferable because the heavy metal has a function of decomposing hydrogen peroxide.

The amount of carbon dioxide present in the reaction system is
Although it depends on the conditions such as the composition of the working solution and the reaction temperature, C
The amount is preferably 0.0001 to 10 times the molar amount of hydrogen peroxide used as O ₂ . The reason is as follows. In the present invention, in the range where the amount of carbon dioxide in the reaction system is within a certain amount, the production rate of ketazine gradually increases as the amount of carbon dioxide increases, that is, the ketazine yield at a certain reaction time gradually increases. To do. Therefore,
The effect of the present invention is exhibited if carbon dioxide is present in the reaction system even in a very small amount. However, even if the amount of carbon dioxide is increased to a certain amount or more, no further increase in the rate of ketazine formation is observed, and if the amount of carbon dioxide present is too large, ammonium salts such as ammonium carbonate will precipitate in the device and Trouble such as blockage is likely to occur.

The synthesized ketazine is separated from the working solution by a settler or the like and hydrolyzed to produce hydrazine. As a method of hydrolysis, a fixed ratio of ketazine and water are continuously supplied to a distillation column to carry out a hydrolysis reaction under pressure to obtain a ketone as a distillate and an aqueous hydrazine solution as a bottom product. The method is common.

[0015]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples. Example 1 In a glass 200 ml four-necked flask equipped with a stirrer, cacodylic acid 3 g, 1,3-butanediol 92 g, and water 5
g and 8-g quinoline 0.1 g were charged and the working solution was saturated with ammonia by continuously blowing ammonia gas while maintaining the temperature at 50 ° C. 22 g of ammonium carbonate (10 g as CO ₂ ) in this liquid
Then, while blowing in ammonia, 14.4 g (0.2 mol) of methyl ethyl ketone and 5.7 g (0.1 mol) of 60% hydrogen peroxide aqueous solution were simultaneously added over 20 minutes, and then reacted for 120 minutes. Allowed (total reaction time 1
40 minutes). When the amount of ketazine in the reaction solution was quantified by gas chromatography, the yield of ketazine obtained was 76% based on the added hydrogen peroxide.

Examples 2 to 11 The reaction conditions and results of Example 1 were changed, and the reaction conditions and results are shown in Table 1 as Examples 2 to 11. Comparative Examples 1 to 7 Examples 1 to 7 except that ammonium carbonate was not added
The results obtained in the same manner as in Example 7 are shown in Table 1 as Comparative Examples 1 to 7. Comparative Example 8 Table 1 shows the result of Comparative Example 8 performed in the same manner as in Example 7 except that cacodylic acid was not used.

Example 12 1 L (2 g) of carbon dioxide gas was used instead of ammonium carbonate.
Was carried out in the same manner as in Example 2 except that the compound was blown into the reaction solution, and the yield of ketazine was 63%. Example 13 The procedure of Example 7 was repeated except that carbon dioxide gas was continuously blown at a rate of 6 mL / min during the reaction without adding ammonium carbonate, and the yield of ketazine was 57%. Met. Example 14 The procedure of Example 7 was repeated except that methylarsonic acid was used instead of cacodylic acid, and the yield of ketazine was 6
It was 6%. Comparative Example 9 The procedure of Comparative Example 7 was repeated except that methylarsonic acid was used instead of cacodylic acid, and the yield of ketazine was 5
7%.

[0018]

According to the present invention, ketazine can be synthesized with high selectivity, high yield and high reaction rate, and hydrazine can be economically produced.

[0019]

[Table 1]

Claims (7)

[Claims] 1. A method for producing hydrazine by reacting a ketone with ammonia and hydrogen peroxide in the presence of a working solution containing an organic arsenic compound to synthesize ketazine, and hydrolyzing the ketazine to produce hydrazine. A method for producing hydrazine, which comprises synthesizing ketazine in the presence of hydrazine. 2. A method for producing ketazine, which comprises reacting a ketone with ammonia and hydrogen peroxide in the presence of a working solution containing an organic arsenic compound, wherein carbon dioxide is present. 3. The organic arsenic compound is represented by the general formula (1) RR′As (═O) X or R ″ As (═O) XY (1) (R, R ′, R ″ are alkyl groups, aralkyl groups or aryls. Group is X, Y is an alkyl group, an aralkyl group, an aryl group, a halogen, a hydroxyl group or an alkoxy group). 4. The amount of carbon dioxide is 0.00 of hydrogen peroxide.
A molar amount of from 01 to 10 times.
The manufacturing method according to any one of 3 above. 5. The production method according to claim 1, wherein the ketone is selected from the group consisting of acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone. 6. The manufacturing method according to claim 1, wherein the working solution is an alcohol solution. 7. The method according to claim 6, wherein the alcohol is ethylene glycol or 1,3-butanediol.