JPH0639454B2 - Method for producing chloroalkylamine hydrochloride - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing chloroalkylamine hydrochloride.

Chloroalkylamine hydrochloride is used in medicine, agricultural chemicals, dyes and pigments,
It is an extremely useful substance as an intermediate for various other industrial chemicals and a modifier for polymer compounds, and a high purity product (purity 98.0% by weight or more) is demanded in the market.

(Prior Art) A method for producing chloroalkylamine hydrochloride by the reaction of alkanolamine hydrochloride and hydrogen chloride gas is known.
For example, in JP-A-56-133247, 2-chloroethylamine characterized in that ethanolamine hydrochloride is reacted with hydrogen chloride gas as a chlorinating agent to remove by-product water out of the reaction system. A method of making the hydrochloride salt is described.

JP-A-57-179133 discloses a compound represented by the general formula (I) (In the formula, R ₁ , R ₂ , R ₃ and R ₄ represent a hydrogen atom or a lower alkyl group and may be the same or different. N is an integer of 2 to 4. At this time, each carbon R ₃ and R ₄ attached to the atom may be the same or different from each other), and alkanolamines represented by the formula (II) (Wherein R ₁ , R ₂ , R ₃ , R ₄ and n are represented by the general formula (I)
In the reaction system consisting of the alkanolamines (I) and the chloroalkylamine hydrochlorides (II). At the time when the amine hydrochlorides had a composition of at least 40 mol% or more in the reaction system, the reaction system was in a state in which substantially no water was contained. A method for producing chloroalkylamine hydrochlorides is described, which comprises further promoting the chlorination reaction of unreacted alkanolamines in the above reaction system using hydrogen chloride gas.

Japanese Unexamined Patent Publication (Kokai) No. 58-41842 describes a method for producing a chloroalkylamine hydrochloride, which comprises reacting a molten alkanolamine hydrochloride with hydrogen chloride gas while removing water.

However, in these methods, the reaction is complicated while removing the by-product water, so the reaction becomes complicated, and a large amount of hydrogen chloride gas is required, which is economically disadvantageous.

Therefore, the present inventors investigated a method for producing chloroalkylamine hydrochloride by using a cheaper hydrogen chloride aqueous solution without using hydrogen chloride gas as a chlorinating agent. However, when an aqueous solution of hydrogen chloride is used, the purity of the obtained chloroalkylamine hydrochloride is about 90%, and the reaction solution contains impurities such as hydrochloric acid and unreacted alkanolamine hydrochloride in addition to chloroalkylamine hydrochloride. , The desired purity (9
(8% by weight or more) requires further purification.

(Problems to be Solved by the Invention) As a conventionally known purification method of chloroalkylamine hydrochloride, a method of recrystallizing crude chloroalkylamine containing impurities in an organic solvent, for example, JP-A-57-17
No. 9135 is known.

However, in this purification method, the reaction solution contains a large amount of impurities, and the chloroalkylamine hydrochloride is purified to a desired purity (98%).
Recrystallization must be repeated in order to adjust the content to at least 1% by weight, and the purification efficiency is reduced.

Furthermore, since chloroalkylamine hydrochloride purified by recrystallization is naturally obtained only as crystals, a step of re-dissolving in water is required to meet the market as an aqueous solution of chloroalkylamine hydrochloride.

As a method for solving these problems, JP-A-62-4
According to Japanese Patent No. 5566, a crude chloroalkylamine hydrochloride is neutralized with an alkali in the presence of an organic solvent, extracted as an organic solvent as free chloroalkylamine, and then an acid is added thereto to obtain a chloroalkylamine salt. However, since alkali metal and alkaline earth metal hydroxides are used as the alkali for neutralizing the crude chloroalkylamine hydrochloride, it contains alkali metal and alkaline earth metal chlorides after neutralization. The aqueous solution must be treated as a waste liquid, and unreacted alkanolamine hydrochloride is completely neutralized at the time of neutralization, and all is treated as a waste liquid without being collected in the aqueous layer as free alkanolamine, which is economical. It is a disadvantage.

As a result of earnest studies for economically producing the chloroalkylamine hydrochloride of the reaction solution with high purity, the present inventors have obtained (1) an alkanolamine or an alkanolamine hydrochloride and a hydrogen chloride aqueous solution. The alkanolamine hydrochloride and other impurities in the obtained crude chloroalkylamine hydrochloride are separated into the aqueous layer by adding and extracting the reaction raw material alkanolamine in the presence of an organic solvent, and are separated into chloroalkylamine hydrochloride. Is extracted as high-purity free chloroalkylamine into the organic solvent layer.

(2) The free chloroalkylamine extracted in the organic solvent layer can be isolated as high-purity chloroalkylamine hydrochloride by neutralizing with hydrogen chloride gas or an aqueous hydrogen chloride solution.

(3) Most of the alkanolamine, which is a reaction raw material used for neutralizing chloroalkylamine hydrochloride, is separated into an aqueous layer as alkanolamine hydrochloride, and unreacted alkanolamine hydrochloride also remains in the aqueous layer. Since the layer is dehydrated as necessary and can be repeatedly used as a reaction raw material, the substantial yield is 1 even when the yield in the reaction is low.
The inventors have found that a value close to 00% can be obtained, and completed the present invention.

(Means for Solving Problems) The present invention is a method of reacting an alkanolamine with hydrogen chloride to produce an alkanolamine hydrochloride, and obtaining a crude chloroamine obtained by reacting the obtained alkanolamine hydrochloride with an aqueous hydrogen chloride solution. Alkylamine hydrochloride in the presence of an organic solvent,
After adding alkanolamine, which is a reaction raw material of the alkanolamine hydrochloride, and extracting it into an organic solvent as free chloroalkylamine, hydrogen chloride gas or an aqueous solution of hydrogen chloride is added thereto to obtain chloroalkylamine hydrochloride, and further added alkanol. The amine is alkanolamine hydrochloride, which is repeatedly used as a reaction raw material of chloroalkylamine hydrochloride together with unreacted alkanolamine hydrochloride, and a method for producing chloroalkylamine hydrochloride and alkanolamine hydrochloride and hydrogen chloride aqueous solution. The crude chloroalkylamine hydrochloride obtained by the reaction is added with alkanolamine, which is a reaction raw material of the alkanolamine hydrochloride, in the presence of an organic solvent, and extracted into an organic solvent as free chloroalkylamine, and then hydrogen chloride gas is added thereto. Or salt A chloroalkylamine hydrochloride is added with an aqueous hydrogen solution, and the added alkanolamine is changed to an alkanolamine hydrochloride, which is repeatedly used as a reaction raw material of chloroalkylamine hydrochloride together with unreacted alkanolamine hydrochloride. The present invention relates to the manufacturing method of the first term of the range.

The chloroalkylamine hydrochloride reaction solution in the present invention is
Alkanolamine or alkanolamine hydrochloride and hydrogen chloride aqueous solution at 100 to 180 ° C. under normal pressure or pressure.
After the reaction, free hydrogen chloride in the reaction solution is removed, and water is further added to form an aqueous solution, which is preferably used in the subsequent extraction and purification step with an organic solvent. Further, the removed hydrogen chloride can be recovered and repeatedly used in the reaction raw material and the subsequent purification step.

The chloroalkylamine hydrochloride produced according to the present invention has the general formula (In the formula, R ₁ , R ₂ , R ₃ and R ₄ represent a hydrogen atom or a lower alkyl group and may be the same or different from each other. Further, n represents an integer of 2 to 6. At this time, R ₃ and R ₄ attached to each carbon atom may be the same or different from each other, and examples thereof include 2-chloroethylamine hydrochloride, 2-dimethylaminoethyl chloride hydrochloride, 2-diethylamiethyl chloride. Hydrochloride, 2-diisopropylaminoethyl chloride hydrochloride, 3-dimethylaminopropyl chloride hydrochloride, 2-methylaminoethyl chloride hydrochloride, 2-ethylaminoethyl chloride hydrochloride, 2-ethylaminopropyl chloride hydrochloride, etc. .

The organic solvent used in the present invention is n-hexane,
Hydrocarbons such as cyclohexane, benzene and toluene,
It is selected from halogenated hydrocarbons such as dichloromethane, chloroform and dichloroethane, ethers such as diethyl ether and diisopropyl ether, and ketones such as methyl ethyl ketone and methyl isobutyl ketone. The amount of the organic solvent used is 1 to 3 times the weight of the amount of chloroalkylamine hydrochloride in the reaction solution. Solvent amount is 1
If the amount is less than the double amount, the yield of chloroalkylamine hydrochloride is significantly reduced, and use of the triple amount or more is disadvantageous because the yield cannot be improved.

The alkanolamine used for neutralizing the reaction solution in the present invention is an alkanolamine used as a reaction raw material for the chloroalkylamine hydrochloride produced, and examples thereof include ethanolamine, N, N-dimethylethanolamine, and N, N.
-Diethylethanolamine, N, N-diisopropylethanolamine, N, N-dimethylpropanolamine, N-methylethanolamine, N-ethylethanolamine, N-ethylpropanolamine and the like,
These alkanolamines are used as they are or as an aqueous solution.

As a neutralization method, it is preferable to add alkanolamine as a reaction raw material dropwise to a mixture of the reaction solution and an organic solvent.

On the contrary, dropping the reaction solution into the alkanolamine is not preferable because it causes dehalogenation and quaternary ammonium formation, resulting in a low yield.

The neutralization temperature is preferably as low as possible in order to suppress the dehalogenation reaction. However, at low temperatures, the chloroalkylamine salt precipitates and becomes a sherbet, so it is usually 5 to 3
Neutralization is performed at 0 ° C, preferably 10 to 20 ° C.

The amount of alkanolamine used for neutralization is in the range of 0.9 to 1.1 times the molar amount of chloroalkylamine hydrochloride in the reaction solution, in addition to the number of moles of free hydrogen chloride in the reaction solution. Is suitable. When the molar ratio is 0.9 or less, the purity of the free chloroalkylamine extracted in the organic solvent is no longer improved, and conversely, the amount of chloroalkylamine hydrochloride remaining in the aqueous layer without being neutralized increases ( 20% by weight or more of the chloroalkylamine hydrochloride to be purified) The purification efficiency decreases. When the molar ratio is 1.1 or more, the extraction amount of free chloroalkylamine increases (95% by weight or more of the purified chloroalkylamine hydrochloride), but the extraction amount of excess alkanolamine into the organic solvent increases, and The purity of the free chloroalkylamine in the solvent is reduced. (98% by weight or less)
The neutralization time is preferably 3 hours or less in order to suppress the above-mentioned side reaction.

Most of the alkanolamine used for neutralization remains in the aqueous layer as alkanolamine hydrochloride, and this aqueous layer is separated and dehydrated as necessary to be used repeatedly as a reaction raw material for chloroalkylamine hydrochloride. To be done. or,
This water layer also contains unreacted alkanolamine hydrochloride and unextracted chloroalkylamine, and these also return to the reaction system.

The free chloroalkylamine extracted into the organic solvent by neutralization is unstable and partly becomes a quaternary ammonium during storage, so it can be stored stably by neutralizing with an acid and isolating as a chloroalkylamine salt. Like

Hydrogen chloride gas or hydrogen chloride aqueous solution is used as the acid.

To neutralize the free chloroalkylamine, the acid may be added to the organic solvent solution of the free chloroalkylamine, or conversely, the organic solvent solution of the free chloroalkylamine may be added to the acid. The reaction temperature is 10 to 30 ° C and the pH is 1 to
5 is suitable.

When neutralized with hydrogen chloride gas, the chloroalkylamine hydrochloride precipitates as crystals, so the crystals are made into a product by drying and drying, and the liquid is repeatedly used in the neutralization step. When neutralized with an aqueous solution of hydrogen chloride, it is obtained as an aqueous solution of chloroalkylamine hydrochloride, the aqueous layer is isolated as a product by liquid separation, and the organic solvent layer is repeatedly used in the neutralization step.

(Effects of the Invention) By the production method of the present invention, a high-purity chloroalkylamine hydrochloride can be easily obtained, and both the crystal and the aqueous solution can be easily adjusted depending on the use, and the chloroalkyl is industrially extremely economical. Amine hydrochloride is produced and used in many applications.

(Examples) Hereinafter, the present invention will be specifically described with reference to Examples, but these are merely examples and the present invention is not limited to these Examples.

Example-1 N, N-dimethylethanolamine hydrochloride (water content) prepared in N, N-dimethylethanolamine and 36 wt% hydrochloric acid in a glass autoclave 3 equipped with a stirrer, temperature control means, and pressure control means. 1.0 wt%) 380.4
g (3.0 mol) and 36 wt% hydrogen chloride aqueous solution 151
9.2 g (15 mol as hydrogen chloride) was charged, the temperature was gradually raised, and the reaction was continued at 150 ° C. for 10 hours. During this time, the pressure changed from 9 kg / cm ² G to 6 kg / cm ² G.

After completion of the reaction, the reaction mixture was cooled and the contents were taken out, and concentrated and dried under reduced pressure of 30 mmHg at 80 ° C. for 2 hours to obtain a crude product (purity as 2-dimethylaminoethyl chloride hydrochloride 82.3).
(Wt%) 446.1 g was obtained (conversion rate 85.0%).

To 175.0 g of this crude product, 80.7 g of water was added and dissolved while stirring, and 216.1 g of toluene was added thereto, and while stirring and cooling, 84.6 g of N, N-dimethylethanolamine was added at 10 to 15 ° C. It dripped over about 15 minutes.

Immediately after liquid separation by standing, hydrogen chloride gas was passed through the toluene layer at 20 to 25 ° C. at 35 Nl / Hr to adjust the pH to 1.3.

The produced crystals were filtered and dried to obtain 134.6 g of white crystals. As a result of the analysis, the purity of 2-dimethylaminoethyl chloride hydrochloride was 99.5%. The purification yield from the crude product was 93.0%.

In addition, the above-mentioned N, N-dimethylethanolamine was added dropwise, and the aqueous layer separated from the toluene layer was separated under reduced pressure of 30 mmHg for 8
Concentrate at 0 ° C., containing 1.0% by weight water 169.
9 g was obtained. As a result of analysis, the composition of the concentrate was 94.7% by weight of N, N-dimethylethanolamine hydrochloride and 4.3% by weight of 2-dimethylaminoethyl chloride hydrochloride. The entire amount of the concentrate was charged into the above-mentioned glass autoclave, and a 36% by weight hydrogen chloride aqueous solution was added to the solution of 669.
3 g was charged, the temperature was gradually raised, and the reaction was continued at 150 ° C. for 10 hours. After completion of the reaction, the contents were taken out by cooling and concentrated to dryness under reduced pressure of 30 mmHg at 80 ° C. for 2 hours to give a crude product (purity as 2-dimethylaminoethyl chloride hydrochloride 83.3% by weight) 198. 4 g was obtained. (Conversion rate 85.6%) To this crude product was added 81.6 g of water and dissolved with stirring. To this was added 247.9 g of toluene, and with stirring and cooling, N, N-dimethyl was added at 10 to 15 ° C. 97.2 g of ethanolamine was added dropwise over about 15 minutes.

Immediately after standing and separating the liquid, hydrogen chloride gas was passed through the toluene layer at 20 to 25 ° C. at 35 Nl / Hr to adjust the pH to 1.3.

The produced crystals were filtered and dried to obtain 154.8 g of white crystals. As a result of the analysis, the purity of 2-dimethylaminoethyl chloride hydrochloride was 99.4%. The purification yield from the crude product was 93.1%.

By the same operation, N, N-dimethylethanolamine hydrochloride was recycled three more times, and the results shown in Table 1 were obtained.

Example-2 80.7 g of water was added to 175.0 g of the crude product obtained in Example-1.
Was added and dissolved with stirring, to which dichloroethane 2 was added.
16.1 g was added, and 84.6 g of N, N-dimethylethanolamine was added at about 15 to 15 ° C. while stirring and cooling.
It dripped over minutes. Immediately after the stationary separation, a 36 wt% aqueous hydrogen chloride solution was added dropwise to the dichloroethane layer at 20 to 25 ° C. to adjust the pH to 1.3.

The aqueous layer was separated to obtain 193.3 g of a 2-dimethylaminoethyl chloride hydrochloride aqueous solution. As a result of the analysis, the purity of 2-dimethylaminoethyl chloride hydrochloride is 99.2%.
Met. The purification yield from the crude product was 91.8%.

Further, the aqueous layer obtained by separating the dichloroethane layer after the dropping of N, N-dimethylethanolamine as described above was concentrated at 80 ° C. under a reduced pressure of 30 mmHg to obtain a concentrate 1 containing 1.0% by weight of water.
69.1 g was obtained. As a result of the analysis, the composition of the concentrate was N,
95.5% by weight of N-dimethylethanolamine hydrochloride,
It was 3.5% by weight of 2-dimethylaminoethyl chloride hydrochloride. The entire amount of the concentrate was charged in the same glass autoclave as in Example 1, and 674.7 g of a 36 wt% hydrogen chloride aqueous solution was further charged, and the temperature was gradually raised.
The reaction was continued at 0 ° C for 10 hours. After completion of the reaction, the contents were taken out by cooling and concentrated to dryness under reduced pressure of 30 mmHg at 80 ° C. for 2 hours to obtain a crude product (purity as 2-dimethylaminoethyl chloride hydrochloride 83.1% by weight) 199. 6
g was obtained. (Conversion rate 85.4%) To this crude product, 92.1 g of water was added and dissolved with stirring, to which was added 248.7 g of dichloroethane, and the mixture was stirred,
While cooling, 97.5 g of N, N-dimethylethanolamine was added dropwise at 10 to 15 ° C over about 15 minutes.

Immediately after standing and separating the liquid, hydrogen chloride gas was passed through the toluene layer at 20 to 25 ° C. at 35 Nl / Hr to adjust the pH to 1.3.

The aqueous layer was separated to obtain 261.0 g of a 2-dimethylaminoethyl chloride hydrochloride aqueous solution.

As a result of analysis, the purity of 2-dimethylaminoethyl chloride hydrochloride was 99.2%. The purification yield from the crude product was 92.0%.

By the same operation, N, N-dimethylethanolamine hydrochloride was recycled three more times, and the results shown in Table-2 were obtained.

Example-3 550.5 g of N, N-diisopropylethanolamine hydrochloride (water content 1.0% by weight) was added to a glass autoclave 3 equipped with a stirrer, temperature control means, and pressure control means.
(3.0 mol) and 36 wt% hydrogen chloride aqueous solution 151
9.2 g (15 mol as hydrogen chloride) was charged, the temperature was gradually raised and the reaction was continued at 150 ° C. for 30 hours. During this time, the pressure changed from 10 kg / cm ² G to 7 kg / cm ² G.
After completion of the reaction, the contents were taken out by cooling and concentrated to dryness under reduced pressure of 30 mmHg at 80 ° C. for 2 hours to obtain a crude product (purity as 2-diisopyraminoethyl chloride hydrochloride 8
622.1 g was obtained (conversion rate 83.0).
%).

To this crude product (250.0 g) was added water (115.4 g) with stirring, and toluene (300.4 g) was added thereto with stirring and cooling. At 10 to 15 ° C., N, N-diisopropylethanolamine (138.0 g) was added. It dripped over about 15 minutes.

Immediately after liquid separation by standing, hydrogen chloride gas was passed through the toluene layer at 20 to 25 ° C. at 35 Nl / Hr to adjust the pH to 1.3.

The produced crystals were filtered and dried to obtain 191.1 g of white crystals. As a result of the analysis, the purity of 2-diisopropylaminoethyl chloride hydrochloride was 99.5%. The purification yield from the crude product was 95.0%.

Further, the above-mentioned N, N-diisopropylethanolamine was added dropwise and the aqueous layer separated from the toluene layer was concentrated at 80 ° C. under a reduced pressure of 30 mmHg to obtain a concentrate 2 containing 1.0% by weight of water.
18.9 g was obtained. As a result of the analysis, the composition of the concentrate was N,
It was 94.5% by weight of N-diisopropylethanolamine hydrochloride and 4.5% by weight of 2-diisopropylaminoethyl chloride hydrochloride. The entire amount of the concentrate was charged into the glass autoclave described above, and 602.5 g of 36 wt% hydrogen chloride aqueous solution was further charged therein, and the temperature was gradually raised to 1
The reaction was continued at 50 ° C. for 30 hours. After completion of the reaction, the contents were taken out by cooling and concentrated to dryness under reduced pressure of 30 mmHg at 80 ° C. for 2 hours to obtain a crude product (purity as 2-diisopropylaminoethyl chloride hydrochloride 81.1% by weight) 2
49.1 g was obtained. (Conversion rate 83.5%) To this crude product was added 114.9 g of water and dissolved with stirring. To this was added 303.2 g of toluene, and with stirring and cooling, N, N-diisopropyl was added at 10 to 15 ° C. 139.4 g of ethanolamine was added dropwise over about 15 minutes.

Immediately after standing and separating the liquid, hydrogen chloride gas was passed through the toluene layer at 20 to 25 ° C. at 35 Nl / Hr to adjust the pH to 1.3.

The produced crystals were filtered and dried to obtain 192.6 g of white crystals. As a result of the analysis, the purity of 2-diisopropylaminoethyl chloride hydrochloride was 99.5%. The purification yield from the crude product was 94.8%.

By the same operation, N, N-diisopropylethanolamine hydrochloride was recycled three more times, and the results shown in Table 3 were obtained.

Example-4 250.0 g of the crude product obtained in Example-3 was added with water 115.4.
30 g of methyl isobutyl ketone is added to this, and the mixture is stirred and cooled to 10 g.
N, N-diisopropylethanolamine 1 at -15 ° C
38.0g was dripped over about 15 minutes. Immediately after the stationary separation, a 36 wt% aqueous hydrogen chloride solution was added dropwise to the methyl isobutyl ketone layer at 20 to 25 ° C. to adjust the pH to 1.3.

The aqueous layer was separated to obtain 248.1 g of a 2-diisopropylaminoethyl chloride hydrochloride aqueous solution. Analysis result, 2
The purity of diisopropylaminoethyl chloride hydrochloride was 99.3%. The purification yield from the crude product is 9
It was 3.0%.

In addition, after the above-mentioned N, N-diisopropylethanolamine was dropped, a water layer separated from the methylisobutylketone layer was separated,
Concentrated at 80 ℃ under reduced pressure of 30mmHg, water content 1.0%
224.4 g of a concentrate containing As a result of analysis, the composition of the concentrate was 94.5% by weight of N, N-diisopropylethanolamine hydrochloride and 4.5% by weight of 2-diisopropylaminoethyl chloride hydrochloride. The entire amount of the concentrate was charged in the same glass autoclave as in Example 3, and 565.3 g of a 36 wt% hydrogen chloride aqueous solution was further charged, and the temperature was gradually raised and the reaction was continued at 150 ° C. for 30 hours. After the reaction was completed, the contents were taken out by cooling and
The mixture was concentrated to dryness under reduced pressure of mmHg at 80 ° C. for 2 hours to obtain 252.7 g of a crude product (purity 81.1% by weight as 2-diisopropylaminoethyl chloride hydrochloride). (Conversion rate 83.4%) 116.7 g of water was added to this crude product and dissolved while stirring, and 307.3 g of methyl isobutyl ketone was added to this crude product, and N, N at 10 to 15 ° C while stirring and cooling. 141.2 g of diisopropylethanolamine was added dropwise over about 15 minutes.

Immediately leave it still, and after separating the liquid, add 36 to the methylisobutylketone layer.
Aqueous solution of hydrogen chloride in weight% is added dropwise at 20 to 25 ° C to adjust the pH.
Adjusted to 1.3.

The aqueous layer was separated to obtain 290.0 g of 2-diisopropylaminoethyl chloride hydrochloride aqueous solution. Analysis result, 2
The purity of diisopropylaminoethyl chloride hydrochloride was 99.3%. Met. The purification yield from the crude product was 93.3%.

By the same operation, N, N-diisopropylethanolamine hydrochloride was recycled three more times, and the results shown in Table 4 were obtained.

Claims (2)

[Claims] 1. A alkanolamine hydrochloride is produced by reacting an alkanolamine with hydrogen chloride, and the crude chloroalkylamine hydrochloride obtained by reacting the obtained alkanolamine hydrochloride with an aqueous solution of hydrogen chloride is present in the presence of an organic solvent. under,
After adding alkanolamine, which is a reaction raw material of the alkanolamine hydrochloride, and extracting it into an organic solvent as free chloroalkylamine, hydrogen chloride gas or an aqueous solution of hydrogen chloride is added thereto to obtain chloroalkylamine hydrochloride, and further added alkanol. A process for producing a chloroalkylamine hydrochloride, characterized in that the amine is an alkanolamine hydrochloride and is repeatedly used as a reaction raw material of the chloroalkylamine hydrochloride together with an unreacted alkanolamine hydrochloride. 2. A crude chloroalkylamine hydrochloride obtained by the reaction of an alkanolamine hydrochloride with an aqueous solution of hydrogen chloride is added with an alkanolamine which is a reaction raw material of the alkanolamine hydrochloride in the presence of an organic solvent to give a free chloroalkylamine. After extraction as an amine into an organic solvent, hydrogen chloride gas or an aqueous solution of hydrogen chloride is added thereto to give a chloroalkylamine hydrochloride, and the added alkanolamine is changed to an alkanolamine hydrochloride, which is then reacted with a chloroalkylamine hydrochloride. The production method according to claim 1, wherein the salt is repeatedly used as a reaction raw material.