JPH0228588B2 - NNARUKIRUECHIRENJIAMINRUINOSEIZOHOHO - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present inventors have previously made a new invention regarding a method for producing N-ethylethylenediamine, and filed a Japanese Patent Application No. 1983-8305 regarding this invention. The present inventors discovered that N-alkylethylenediamines having an alkyl group having 3 to 6 carbon atoms in place of the ethyl group of the object compound of the invention can also be obtained by the same method, resulting in the present invention. .

That is _, the present invention provides _N-
This invention relates to a method for producing alkylethylenediamines. An alkyl halide in which the alkyl is from _C3 to about _C6 and ethylenediamine (EDA) are mixed at a temperature of about -10°C to about 120°C and in a molar ratio of EDA to the alkyl halide of about 1 to 20:1 with about 0 water. ~50
% by weight to form a reaction mixture containing N-alkylethylenediamines. The resulting reaction mixture is then contacted with an aqueous alkalizing agent to form a mixture of inorganic halide, an aqueous phase, and an organic phase, and the organic phase is separated from the mixture. The organic phase is diluted with about 0.02-100% by weight of a suitable hydrocarbon and the resulting mixture is azeotropically fractionated to remove all water and unreacted EDA. The resulting reaction mixture was then fractionally distilled to remove residual hydrocarbon solvents and the N-alkylethylenediamine was distilled to about 99
% purity or higher.

The reaction between the alkyl halide and EDA is approximately 25
A molar ratio of EDA to alkyl halide of about 2-5:1 in the presence of about 0-30% water by weight at ~50°C.
It is preferable to do so. The reaction mixture obtained is then contacted with an aqueous caustic soda solution and the organic phase is diluted with about 0.02 to 20% by weight of hydrocarbon solvent before carrying out the distillation.

The method of the present invention can be modified by adding the following steps (1) to (3). (1) recovering and recycling aqueous EDA from the azeotrope; (2) recovering and recycling hydrocarbons; and (3) adding the separated and alkaline aqueous phase to the organic phase. contacting with about 10-100% by weight of said hydrocarbon solvent based on the weight of said hydrocarbon solvent, separating the extracted aqueous phase, and diluting the organic phase with the hydrocarbon extract before performing azeotropic fractional distillation.

The present invention also includes adding a suitable hydrocarbon solvent to the N-alkylethylene diamine mixture, azeotropically fractionating water and/or EDA from the resulting mixture, further fractionally distilling to remove residual hydrocarbon solvent, and anhydrous and/or N- without EDA
Water and/or
Or a method that provides a method for removing EDA. The advantages of the method of the present invention over previously used methods are that (1) the final product has a purity of about 99% or more, and (2) the method produces high yields and high productivity. .

According to the present invention, there is also provided a separate method for producing N-alkylethylenediamine with a purity of about 99% or more, which includes the following steps (a) to (h). (a) Alkyl halide and
EDA to the alkyl halide in a molar ratio of about 1 to 20:1 and at a temperature of about -10°C to about
reacting at 120° C. and under anhydrous conditions to obtain an alkylation reaction mixture; (b) adding thereto about 0.02 to 30% by weight of a suitable hydrocarbon solvent based on the weight of the alkylation reaction mixture; (c) substantially removing EDA from said mixture by azeotropic fractional distillation of the mixture of EDA and said hydrocarbon solvent from said mixture; (d) removing the resulting reactant from said alkyl halide. at least per mole
neutralizing the reaction mixture by contacting with 0.9 molar equivalents of a suitable alkalizing agent to form a slurry of alkali halide precipitate; (e) separating said alkali halide from said slurry and producing a recovering a mother liquor; (f) washing said separated alkali halide with said hydrocarbon solvent; and (g) combining said mother liquor from step (e) and the hydrocarbon wash liquor recovered from step (f); (h) azeotropically fractionating the resulting reaction mixture to remove residual hydrocarbon solvents; (h) azeotropically fractionating the resulting reaction mixture to remove residual hydrocarbon solvents; , and a step of recovering the N-alkylethylenediamine.

EDA (either anhydrous or with water) and an alkyl halide, preferably alkyl chloride, are mixed in a suitable reaction vessel while the reaction mixture is shaken and heated from about -10 to about 120°C (preferably about 25°C). ~50
°C) for about 5-15 hours (preferably about 7-9 hours)
The molar ratio of EDA to alkyl halide is between about 1 and 20:1 (preferably about 2
~5:1) and to form a reaction mixture containing about 0-50% (preferably about 0-30%) water by weight. Suitable alkyl halides include propyl chloride, isopropyl chloride, butyl chloride, pentyl chloride, 1-hexyl chloride, and 3-hexyl chloride. The total residence time in the reaction vessel depends on the temperature used, with higher temperatures resulting in shorter residence times.

The reaction mixture is then brought into vigorous contact with an aqueous solution of an alkalizing agent to form a mixture of an organic phase, an aqueous phase, and an alkali halide. A sufficient alkalizing agent is used so that the pH of the aqueous phase does not fall below about 7, preferably below 8, and which forms an aqueous phase. Suitable alkalizing agents include sodium hydroxide and potassium hydroxide (either alone or in mixtures).
is included. A preferred alkalizing agent is about 50% aqueous sodium hydroxide.

The organic layer is separated from the alkali halide and aqueous layer by phase separation or by first separating the alkali halide by filtration or centrifugation and then by phase separation. This organic layer contains N-alkylethylenediamine and unreacted
EDA and high temperature alkylated products such as N,N′-dialkylethylenediamine,
N,N'-dialkylethylenediamine, N,N,
N′-trialkylethylenediamine and N,
Contains N,N',N'-tetraalkylethylenediamine. The organic layer is then diluted with about 0.02 to 100% by weight, preferably about 0.02 to 20% by weight, based on the weight of the organic layer, of a suitable hydrocarbon solvent.

The separated aqueous layer is approximately
It is preferred to extract with 10-100% by weight, preferably about 10-20% by weight of a suitable hydrocarbon solvent and allow the biphasic mixture to settle. The extracted aqueous layer is then separated and the organic layer is diluted with a hydrocarbon solvent extract.

As used herein, a "suitable hydrocarbon solvent" means a solvent that forms an azeotrope with water and/or EDA at a temperature below the boiling point of the product N-alkylene diamine, and that contains a substantial amount of N-alkylene diamine. an azeotrope condensed without water and/or
Or it means a hydrocarbon solvent that can separate EDA. Suitable hydrocarbon solvents include n-heptane, isooctane, cyclohexane, n-hexane, methylcyclohexane, n-pentane, and the like, with the preferred hydrocarbon solvent being n-heptane.

The diluted organic layer is then passed through a distillation column and heated to boiling to distill off all residual EDA and water. After settling the distillate, the lower EDA-water layer is separated and recycled to the alkylation vessel, and the upper hydrocarbon layer is distilled until an EDA-free anhydrous N-alkylethylenediamine is obtained. Recirculate to the column or transfer to a vessel for extraction of the original aqueous layer.

Contains N-alkylethylenediamine, highly alkylated ethylenediamines and hydrocarbon solvents,
The residual reaction mixture free of EDA is fractionally distilled using a rectification column with a sufficient number of theoretical plates to separate the hydrocarbon solvent from the N-alkylethylenediamine. For example, using a column with 15 theoretical plates and n-heptane as the solvent, the n-heptane is distilled off as a first distillate boiling at about 98-100°C.
The initial distillation of the hydrocarbon solvent thus obtained is:
Dilution of the organic layer, as described above, from the reaction mixture.
It can be recycled to other stages of the process, such as azeotropic distillation of EDA and water, or extraction of the aqueous layer.

After removing the initial distillate of hydrocarbon solvent, distillation continues to produce N-alkylethylenediamine (99% pure) with a yield of over 60% based on the charged alkyl halide.
or more). The method used here involves adding an appropriate amount of the hydrocarbon solvent, azeotropic fractional distillation of water or EDA or both, and fractional distillation of the residue to remove excess hydrocarbon solvent, and
It may be used to remove water and/or EDA from N-alkylethylenediamine by obtaining an anhydrous EDA-free N-alkylethylenediamine. It will be appreciated that the process described above may be carried out continuously using suitable vessels such as continuous flow reactors, splitter vessels, distillation columns and the like.

Alternatively, ethylenediamine as an anhydrous liquid is reacted with an alkyl halide as follows: (Here, X is a halogen atom such as chlorine, bromine or iodine, preferably chlorine). The reaction is carried out in a suitable reaction vessel with a reaction mixture of about -
10°C to about 120°C, preferably about 25 to 75°C
This is carried out with stirring for ˜24 hours, preferably about 2 to 6 hours. The molar ratio of EDA to alkyl halide used is about 1 to 20:1, preferably about 2 to 5:1. The total residence time in the reaction vessel depends on the temperature used, but the residence time will be shorter if higher temperatures are used.

Once the reaction is complete, about 0.02-30% by weight, preferably about 0.5-1.0% by weight, based on the weight of the reaction mixture.
Dilute the reaction mixture using a suitable hydrocarbon solvent. The term "suitable hydrocarbon solvent" as used herein has the same meaning as above. The diluted reaction mixture is then passed through a distillation column and heated to boiling to azeotropically fractionate residual EDA. Optionally, the EDA distillate may be recovered and recycled.

Suitable hydrocarbon solvents include n-heptane, isooctane, cyclohexane, n-hexane, methylcyclohexane, n-pentane, and the like, with the preferred hydrocarbon solvent being n-heptane.

The reaction mixture is then neutralized by contacting with at least 0.9 molar equivalents of a suitable alkalizing agent per mole of alkyl halide used. As used herein, "a suitable alkalizing agent" refers to sodium hydroxide or potassium hydroxide (either alone or in mixtures). A preferred alkalizing agent is 50% aqueous sodium hydroxide.

The resulting alkali halide precipitate is separated from the product slurry by conventional means such as filtration or centrifugation and washed with the hydrocarbon solvent described above, preferably n-heptane.

The hydrocarbon solvent wash is recovered and combined with the mother liquor obtained by adding an alkalizing agent to the reaction mixture and separating the alkali halide precipitate from the resulting slurry. The combined liquid is
It is azeotropically fractionated at atmospheric pressure through a packed column, preferably with recirculation of the heptane distillate to the column, until the residual material is essentially free of EDA and water.

The resulting essentially EDA-free reaction mixture (product N-alkylethylenediamine,
(including highly alkylated ethylenediamine and hydrocarbon solvent) is fractionally distilled using a rectification column having a sufficient number of theoretical plates to separate the hydrocarbon solvent from the product N-alkylethylenediamine. For example, using a column with 15 theoretical plates, n-heptane is distilled off as an initial distillation boiling at about 98-100°C. The initial distillate of hydrocarbon solvent thus obtained may be recycled to other stages of the process, such as dilution of the reaction mixture, EDA from the reaction mixture, or azeotropic distillation of water.

After removing the initial distillate of hydrocarbon solvent, the reaction mixture is preferably clarified to remove insoluble materials and the clarified solution is continued to distill to produce N-alkylethylenediamine with a purity of 99% or higher and a yield of 60% or higher (preparation). (calculated as alkyl halide).

Of course, the above method can be carried out continuously using a suitable vessel such as a fluidized reactor, separation vessel, distillation column or the like.

The following examples are presented to further illustrate the invention.
Unless otherwise indicated, all parts are parts by weight and all ranges are inclusive. Product purity is expressed as area percentage determined by gas phase chromatography (VPC).

Example 1 This example is an example of using anhydrous EDA.

Ethyl chloride (565 g; 8.76 mole) is added to anhydrous EDA (1420 g; 23.63 mole) at 30-40°C over 5 hours. After the addition was complete, the reaction mixture was stirred for 2 hours and 50% caustic soda (935
ml; 17.5 mol). The resulting mixture is stirred for 30 minutes, allowed to settle, and the aqueous slurry of salts is separated and extracted twice with 150 ml of n-heptane. adding a heptane extract to the organic layer, and a rectification column;
using a splitter device to return the distilled heptane to the distillation column and separate the dense aqueous EDA layer.
Heat the combined solution to 88-97°C with water and
Fractionally distill the EDA. In this way, 394g of water
and aqueous EDA consisting of 896 g (14.91 mol) of EDA
Separate the layers. The EDA-free residue is subjected to fractional distillation to produce N-ethylethylenediamine (NEED).
First distillation of heptane containing 3-4% by weight (boiling point 98-102
℃) and VPC to obtain 484 g of NEED (boiling point 130-131℃) with a purity of 99.8% or more. The yield is 62.7% of theory based on ethyl chloride.

Example 2 This example is an example of the use of recovered aqueous EDA. Mixture of aqueous EDA recovered from Example 1 (containing 14.39 moles of EDA) and anhydrous EDA (555 g; 9.23 moles).
30~1245g of ethyl chloride (545g; 8.45mol)
Add over 5 hours at 40°C. After the addition is complete, the reaction mixture is stirred for 2 hours and 50% caustic soda (902 ml; 16.9 mol) is added. The resulting mixture is treated as described in Example 1 with n-heptane recovered from Example 1 to separate and extract the aqueous slurry of salt. Fractional distillation of the EDA-free residual material yields 483 g of heptane initial fraction containing 3-4% by weight of NEED and >99.8% purity by VPC (boiling point 130-131° C.). The yield is 65% of theory based on ethyl chloride.

Example 3 This example uses EDA from N-ethylethylenediamine.
This is an example of separating EDA (500 g) and NEED (500 g) by azeotropic distillation. A mixture of EDA (500 g) and NEED (500 g) is diluted with 200 ml of n-heptane, and then the distillation column and recovered heptane are returned to the distillation apparatus to recover a dense EDA layer. EDA (boiling point 87-90 °C) is azeotropically fractionated from the diluted mixture using an apparatus. According to VPC, the EDA recovered in this way accounts for less than 1%.
Contains NEED. Then, the EDA-free residue is subjected to fractional distillation to recover initial heptane distillate and pure NEED product (boiling point 130-131°C).

Similar results can be obtained by replacing n-heptane with cyclohexane, n-hexane or isooctane as described above.

Example 4 This example is an example of separating water from N-ethylethylenediamine by azeotropic distillation.
Add 50ml. The mixture is heated to boiling and the water is azeotropically fractionated (boiling point 88-98° C.) using a distillation column and a splitter device which returns the recovered heptane to the distillation device to remove the dense aqueous layer.
After water removal is completed, the residue is fractionally distilled to recover NEED (boiling point 130-131°C) containing less than 0.2% water by heptane first distillation and VPC.

Similar results can be obtained by replacing n-heptane with cyclohexane, n-hexane or isooctane in the above method.

Examples 5-10 are examples of recovery of N-ethylethylenediamine prior to neutralization of EDA. Example 5 Stirred ethylenediamine (146.3g; 2.43mol)
Ethyl chloride (62.4 g; 0.967 mol) is added to the solution over a period of 1 hour while the temperature is allowed to rise to 95°C. Once the addition of ethyl chloride is complete, add n-heptane (34.2 g) and add the distillation column and Dean-
The resulting mixture is azeotropically distilled using a Stark apparatus. The Dean-Stark unit recovers a two-layer liquid distillate consisting of ethylene diamine (85.09 g) in the lower layer and heptane in the upper layer, and the heptane is recycled to the rectification column until all the ethylene diamine is removed.

The residual material is cooled to 80 DEG C., neutralized with 50% aqueous sodium hydroxide solution (77.36 g; 0.967 mol), and the sodium chloride formed is separated to yield a percake and two layers of liquid. The overcake is then washed with heptane (50 ml) and the washings are added to the original bilayer solution.

The resulting bilayer liquid is then azeotropically distilled using a rectification column and a Dean-Stark apparatus for recovering a bilayer distillate consisting of n-heptane and water. After all water was removed, the residue was fractionally distilled to remove heptane, yielding 99% pure N-ethylethylenediamine (54.5 g; boiling point 130-131°C; yield 64% of theoretical).
Collect.

Example 6 The procedure of Example 5 is followed exactly up to the final distillation stage. After removing all the water by azeotropic distillation, the remaining material is filtered to separate a white precipitate (4.32 g).
The overcake was then washed with heptane (16 g),
Combine the washing liquid with the liquid. Next, this washing liquid and liquid were combined by fractional distillation to remove heptane, and N-ethylethylenediamine with a purity of 99% (53.7 g; boiling point 130-131°C; yield 63% of theoretical value) was obtained.
Collect.

Example 7 A glass-lined reactor is charged with 848 parts of ethylenediamine (98%), followed by 45 to 50 parts of the reaction mixture.
Charge 331 parts of liquid ethyl chloride through a dipleg at a rate maintained at 55°C. The mixture is stirred for 2 hours and 91 parts of heptane are added to it. Excess ethylenediamine is azeotropically distilled in a packed column while the heptane distillate is recycled from the top. A total of 492 parts of ethylenediamine is recovered from the recycled distillate. Reaction mixture is 50% caustic soda
Neutralize with 402 parts, cool to room temperature, and centrifuge to remove by-product sodium chloride. The salt cake was washed with 70 parts of heptane and the washings were combined with the mother liquor in a glass lined container. Water is azeotropically distilled off from the combined liquids while the distilled heptane is recycled to the packed column from the top. After all the water was removed, heptane was fractionally distilled off through a packed column to obtain a residue containing 273 parts of N-ethylethylenediamine. This residue is saved for later combination with the residues of Examples 8-10.

Example 8 A glass-lined reactor is charged with 492 parts of ethylenediamine recovered from Example 7 and 375 parts of fresh ethylenediamine (98%). To this mixture is charged 331 parts of ethyl chloride at a rate that maintains the reaction mixture at 55-65°C. This mixture was stirred for 2 hours,
45 parts of heptane recovered from Example 7 are then added to this. Excess ethylenediamine is azeotropically distilled through the packed column while the heptane distillate is recycled from the top. A total of 501 parts of ethylenediamine is recovered from the distillate recycle. The reaction mixture is neutralized with 407 parts of 50% caustic soda, cooled to room temperature, and centrifuged to remove by-product sodium chloride. Wash the salt cake with 78 parts of heptane, combining the washings with the mother liquor in a glass-lined container. Water is azeotropically distilled off from the combined liquids through a packed column while recycling the distilled heptane overhead. After removing all the water, heptane is fractionally distilled through a packed column to obtain a residue containing 288 parts of N-ethylethylenediamine. This residue is saved for later combination with the residues of Examples 7, 9 and 10.

Example 9 Recovered from Example 8 in a glass-lined reactor
Charge 501 parts of ethylene diamine and 396 parts of fresh ethylene diamine (98%). To this mixture is charged 331 parts of ethyl chloride at a rate that maintains the reaction mixture at 65-75°C. This mixture was stirred for 2 hours,
28 parts of heptane recovered from Example 8 are then added to this. Excess ethylenediamine is azeotropically distilled off while recycling the heptane distillate to the top through the packed column. A total of 504 parts of ethylenediamine is recovered from the distillate recycle. The reaction mixture is neutralized with 409 parts of 50% caustic soda, cooled to room temperature, and centrifuged to remove by-product sodium chloride.
The salt cake is washed with 82 parts of heptane and the washings are combined with the mother liquor in a glass lined container. Water is azeotropically distilled off from the combined liquids while recycling the distilled heptane to the top through the packed column. After removing all the water, heptane was fractionally distilled off through a packed column, and N-ethylethylenediamine
A residue containing 310 parts is obtained. This residue is saved for later combination with the residues of Examples 7, 8, and 10.

Example 10 A glass lined reactor is charged with 504 parts of ethylenediamine recovered from Example 9 and 388 parts of fresh ethylenediamine (98%). Add ethyl chloride 331 to this mixture at a rate keeping the reaction mixture at 55-65°C.
Prepare the department. The mixture is stirred for 2 hours and 30 parts of heptane recovered from Example 9 are added to it.
Excess ethylenediamine is azeotropically distilled off while recycling the heptane distillate to the top through the packed column.
A total of 523 parts of ethylenediamine is recovered from the distillate recycle. Add 50% caustic soda to the reaction mixture
Neutralize with 409 parts, cool to room temperature, and centrifuge to remove by-product sodium chloride. The salt cake is washed with 91 parts of heptane and the washings are combined with the mother liquor in a glass lined container. Water is azeotropically distilled off from the combined liquids while recycling the distilled heptane to the top through the packed column. After removing all the water, heptane was fractionally distilled off through a packed column, and N-ethylethylenediamine
A residue containing 317 parts is obtained, which is used in Examples 7 and 8.
and the residue from step 9. The resulting substance is fractionally distilled at normal pressure through a packed column, resulting in a boiling point of 129~
1120 parts of N-ethylethylenediamine at 131°C are obtained. Yield is 61.9 of the theoretical amount based on ethyl chloride.
%.

Examples 11 to 13 are examples in which n-propyl halides, isopropyl halides, and n-butyl halides were used in the present invention, respectively.

Example 11 To anhydrous EDA (988.9 g; 16.48 mol) is added n-propyl chloride (327.1 g; 4.16 mol) at 20-24° C. over 1 hour. After the addition is complete, the reaction mixture is
stir for an hour, and add to this 50% caustic soda (392
ml; 7.35 mol) and water (206 ml). The resulting mixture is allowed to settle and the aqueous slurry of salts is separated and extracted twice with 280 ml of n-heptane. Add heptane extract to the organic layer and heat the combined mixture to 88-97°C with water and
The EDA is azeotropically distilled using a splitter device to return the distilled heptane to the distillation device and to separate the dense aqueous EDA layer. Then,
Fractional distillation of the EDA-free residue results in heptane initial distillation (boiling point 97-100℃) and VPC as the main fraction.
341.3 g of Nn-propylethylenediamine (boiling point 60 mm, 75-77°C) with a purity of 99% or more is obtained.
The yield is based on n-propyl chloride, based on the theoretical amount.
It is 79.5%.

Calculated value of C ₅ H ₁₄ N ₂ :
C, 58.77; H, 13.81; N, 27.42 Actual value of C ₅ H ₁₄ N ₂ :
C, 59.08; H, 13.87; N, 27.60 Example 12 To anhydrous EDA (988.9 g; 16.48 mol) is added isopropyl chloride (327 g; 4.16 mol) at 70°C. After the addition was complete, the reaction mixture was gradually heated to 100 °C;
Cool to 25°C, then add 50% caustic soda (391ml;
7.35 mol) and water (206 mol). The resulting mixture is allowed to settle, then the aqueous slurry of salt is separated and extracted twice with 200 ml of n-heptane. Add heptane extract to the organic layer and heat the combined mixture to 88-97°C with water and
The EDA is distilled off azeotropically, using a splitter device to return the distilled heptane to the distillation device and to separate the dense aqueous EDA layer. Then,
Fractional distillation of the EDA-free residue results in heptane initial distillation (boiling point 97-100℃) and VPC as the main fraction.
305 g of N-isopropylethylenediamine (boiling point 136-137°C) with a purity of 99% or more is obtained. The yield is 71.1% of theory based on isopropyl chloride.

Calculated value of C ₅ H ₁₄ N ₂ :
C, 58.77; H, 13.81; N, 27.42 Actual value of C ₅ H ₁₄ N ₂ :
C, 59.16; H, 13.89; N, 27.28 Example 13 To anhydrous EDA (979.0 g; 16.29 mol) is added n-butyl chloride (385.4 g; 4.16 mol) at 20-24°C over 1 hour. After the addition is complete, the reaction mixture is heated to 22~
Stir at 27° C. for 4 hours, then add 50% caustic soda (935 ml; 7.35 mol) and water (207 ml). The resulting mixture is allowed to settle, then the aqueous slurry of salt is separated and extracted twice with 200 ml of n-heptane. Add heptane extract to the organic layer;
The combined mixture is then heated at 88-97°C to azeotropically distill off the water and EDA, with the distilled heptane being returned to the distillation apparatus and a splitter apparatus being used to separate the dense aqueous EDA layer. use The residue is then fractionally distilled to produce the first distillation of heptane (boiling point
96-100℃) and N-n-butylethylenediamine (boiling point 20-100℃) with a purity of 99% or more in VPC as the main fraction.
348g (74-77℃ at 30mm) is obtained. The yield is 71.3% of theory based on n-butyl chloride.

Calculated value of C ₆ H ₁₆ N ₂ :
C, 62.01; H, 13.88; N, 24.11 Actual value of C ₆ H ₁₆ N ₂ :
C, 61.51; H, 13.92; N, 24.13 Additional relationship
-8305 (Special Publication No. 63-37779, Patent No. 1489934)
This invention is an addition to the invention of item (No.).

The invention of Japanese Patent Publication No. 63-3779 is that a specific aliphatic hydrocarbon solvent such as n-heptane is added in the post-treatment process of the reaction mixture of ethylenediamine and ethyl halide, and unreacted ethylenediamine is azeotropically extracted from the resulting mixture. This relates to a method for producing N-alkylethylenediamine having 2 carbon atoms, which is characterized in that it is removed as a. On the other hand, the present invention is the invention of Japanese Patent Publication No. 63-3779, which is characterized in that an alkyl halide having 3 to 6 carbon atoms is used instead of ethyl halide. Relates to a method for producing N-alkylethylenediamine.

Claims (1)

[Scope of Claims] 1. Ethylenediamine (EDA) and an alkyl halide having 3 to 6 carbon atoms in a molar ratio of ethylenediamine to the ethyl halide of about 1 to 20:1, about -10° to about 120°. At a temperature of °C,
reacting in the presence of about 0-50% by weight water to obtain an alkylation reaction mixture; contacting the reaction mixture with an aqueous solution containing about 1-2 molar equivalents of an inorganic alkalizing agent based on the alkyl halide; neutralizing by; separating an aqueous layer from the neutralized organic layer; adding about
0.2-100% by weight n-heptane, isooctane,
An aliphatic hydrocarbon solvent selected from the group consisting of cyclohexane, n-hexane, methylcyclohexane, and n-pentane is added; from the resulting mixture, all of the water and ethylenediamine are converted into an azeotrope of water and the aliphatic hydrocarbon solvent. , fractionally distilled as an azeotrope of ethylenediamine and the aliphatic hydrocarbon solvent or an azeotrope of water, ethylenediamine and the aliphatic hydrocarbon solvent; and then fractionally distilled the resulting reaction mixture to remove residual hydrocarbon solvent. 1. A method for producing N-alkylethylenediamine in which an alkyl group has 3 to 6 carbon atoms, the method comprising the steps of recovering N-ethylethylenediamine (NEED) with a purity of about 99% or more. 2 The molar ratio of the EDA and the alkyl halide to the alkyl halide is 2 to 5:
1 and at a temperature of 25-50° C. in the presence of 0-30% by weight of water to obtain the alkylation reaction mixture; the reaction mixture is neutralized by contacting with an aqueous solution of caustic soda; A method according to claim 1, characterized in that 20% by weight is added to the organic layer. 3. The method according to claim 1, wherein the hydrocarbon is n-heptane. 4. The method according to claim 2, wherein the hydrocarbon is n-heptane. 5. (a) An aqueous EDA solution is recovered from the azeotrope and recycled to react with the alkyl halide, and then (b) hydrocarbon solvent is recovered from the initial distillation of N-alkylethylenediamine and recycled to the distillation mixture. The method for producing N-alkylethylenediamine according to claim 1, further comprising a recycling step. 6. The aqueous layer is based on the weight of the organic layer.
contacting with 10 to 100% by weight of the hydrocarbon solvent;
2. The method of claim 1, further comprising the steps of: separating the extracted aqueous layer; and adding a hydrocarbon extract to the organic layer prior to performing said azeotropic fractional distillation. 7. The aqueous layer is based on the weight of the organic layer.
contacting 10-100% by weight of said recovered hydrocarbon solvent; separating the extracted aqueous layer; and adding a hydrocarbon extract to said organic layer before carrying out said azeotropic fractional distillation. 6. The method of claim 5, further comprising: 8. Claims 3 and 4, characterized in that the alkyl halide is an alkyl chloride.
5. The method according to section 5, or section 7. 9 (a) Alkyl halide having 3 to 6 carbon atoms and ethylenediamine (EDA) in a ratio of about 1 to 20:1
of ethylenediamine to said alkyl halide at a temperature of from about -10° to about 120°C under anhydrous conditions to obtain an alkylation reaction mixture; (b) to said reaction mixture; about 0.2 to 30% by weight n-heptane,
isooctane, cyclohexane, n-hexane,
adding an aliphatic hydrocarbon solvent selected from the group consisting of methylcyclohexane and n-pentane; (c) fractionally distilling ethylenediamine and the aliphatic hydrocarbon solvent to substantially remove the ethylenediamine; (d)
(e) neutralizing the resulting reaction mixture by contacting it with at least 0.9 molar equivalents of a suitable alkalizing agent per mole of said ethyl halide to form a slurry of alkali halide precipitate; separating the alkali halide and recovering the resulting mother liquor; (f) washing said separated alkali halide with said aliphatic hydrocarbon solvent; (g) combining said mother liquor from step (e) and step (f); (h) fractionally distilling the product mixture with the aliphatic hydrocarbon wash liquor recovered to remove substantially all of the water and residual ethylenediamine from the product mixture; Purity of approximately 99% characterized by recovering N-alkylethylenediamine except for
A method for producing N-alkylethylenediamine whose alkyl group has 3 to 6 carbon atoms. 10. The method according to claim 9, wherein the hydrocarbon is n-heptane. 11. The method of claim 9, wherein step (a) is carried out at a temperature of about 25°C to about 75°C. 12. The method of claim 9, wherein the molar ratio of EDA to the alkyl halide in step (a) is from 2 to 5:1. 13 0.2-1.0% based on the weight of the reaction mixture
10. A method according to claim 9, characterized in that said hydrocarbons of: are added to step (b). 14 0.1-1.0% based on the weight of the reaction mixture
A method according to claim 9, characterized in that said n-heptane of is added to step (b). 15. The method according to claim 9, wherein the alkalizing agent in step (d) is a 50% aqueous sodium hydroxide solution. 16. Claim 11, wherein the alkyl halide is an alkyl chloride.
The method according to paragraph 12, paragraph 13 or paragraph 15.