HU182922B - Process for preparing n-ethyl-ethylene-diamine - Google Patents

Abstract

There are provided processes for preparing N-ethylethylenediamine (NEED) in good yield and purity. In one embodiment the process comprises reacting ethylenediamine (EDA) and an ethyl halide at a mole ratio of EPA to said ethyl halide of about 1-20:1 and a temperature of from about -10 DEG C. to about 120 DEG C. in the presence of about 0-50% by weight of water to obtain an alkylation reaction mixture; neutralizing said reaction mixture by contacting with an aqueous solution containing about 1-2 molecular equivalents of an inorganic alkalizing agent based on the ethyl halide; separating the aqueous layer from the neutralized organic layer and adding to said organic layer about 0.2-100% by weight, based on the weight of said organic layer, of a suitable aliphatic of hydrocarbon solvent; azeotropically fractionally distilling all water and EPA from the resulting mixture; and fractionally distilling the resulting reaction mixture to remove residual hydrocarbon solvent and recover NEED. In a modified embodiment the process comprises (a) reacting an ethyl halide and the ethylenediamine (EDA) at a mole ratio of EDA to said ethyl halide of about 1-20 to 1, and at a temperature of about -10 DEG C to about 120 DEG C under anhydrous conditions to obtain an alkylation reaction mixture; (b) adding to said reaction mixture about 0.2-30% by weight of a suitable aliphatic hydrocarbon solvent, based on the weight of said reaction mixture; (c) fractionally distilling the EDA and said aliphatic hydrocarbon solvent to essentially remove EDA; (d) neutralizing the resulting mixture by contacting it with at least 0.9 molecular equivalent of a suitable alkalizing agent, per mole of said ethyl halide, to form a slurry of an alkali halide precipitate; (e) separating said alkali halide precipitate from said slurry and recovering the resulting mother liquor; (f) washing said separated alkali halide with said aliphatic hydrocarbon solvent; (g) fractionally distilling a combination of said mother liquor from step (e) plus recovered aliphatic hydrocarbon wash liquor from step (f) to remove essentially all water and residual EDA from the resulting mixture; and (h) fractionally distilling said resulting mixture to remove residual aliphatic hydrocarbon solvent and recover said NEED.

Description

The present invention relates to an improved process for the preparation of N-ethyl-ethylenediamine of formula (I).

Solutions similar to the process of the invention are disclosed in the following sources:

J. A. C. S. 67, 1581 (1945) describes the preparation of N-alkyl-ethylenediamines by reacting an alkyl chloride or bromide with a large excess of concentrated (95% by weight) ethylenediamine. In the examples, the alkyl substituents in the process are C8-C18 alkyl.

J. of Pharm. Science 57, 2073 (1968) describes the preparation of N-alkyl-ethylenediamines from anhydrous ethylenediamine by reaction with an alkyl halide in a solvent medium. The alkyl substituents can have from 3 to 5 carbon atoms and the yield of the process is 57%.

75, 1370 (1951) to a N-alkyl-ethylenediamine is reacted with 2-bromo-ethylamine to produce N-alkyl-ethylenediamines; the yield of the reaction was 52%.

The process described in U.S. Patent No. 2,868,833 consists of two synthetic steps, namely acylation of ethylenediamine, followed by reduction of the resulting product to N-ethylenediamine.

A process for the preparation of N-ethylenediamine is described in Chemical Abstracts 52. P 11892 b and 50. 1778 f. The process comprises five steps: (1) alkylation of saccharin to N - (3-bromoethyl) saccharin with dibromoethane, (2) alkylation of N- (β-bromoethyl) saccharin with phthalimide a-saccharino- ) To 3-phthalimidoethane, (3) alkylation of α-saccharino-5-phthalimidoethane with diethyl sulfate α- [N-ethyl-2- (methoxycarbonyl) benzenesulfonamido] -3- [2- (methoxy) carbonyl) benzoylamido] ethane, (4) saponification of the compound prepared in Step (3) into α- (N-ethyl-2-carboxybenzenesulfonamide) -5- (2-carboxybenzoylamido) ethane and (5) ) acid hydrolysis of the product of Step (4) to N-ethyl-ethylenediamine dihydrochloride.

According to the invention, the reaction mixture containing N-ethylethylenediamine is prepared by reacting ethylenediamine with ethyl halide at a temperature of -10 to 120 ° C in the presence of 0 to 50% by weight of water. The ethylene diamine is used in the reaction in a molar ratio of ethyl halide to ethyl halide (1-20): 1. The reaction mixture was then treated with an aqueous alkaline solution. A liquid biphasic mixture consisting of an organic phase and an aqueous alkaline phase is formed, and the aqueous alkaline phase is separated. The organic phase was diluted with 0.2-100% by weight of an aliphatic hydrocarbon solvent and the resulting mixture was subjected to fractional azeotropic distillation to remove water and unreacted ethylenediamine. The resulting reaction mixture is then fractionally distilled to remove residual hydrocarbon solvent. In this way, N-ethyl-ethylenediamine is absorbed in a purity greater than 99% by weight.

The ethyl halide and ethylenediamine are reacted in a weight ratio of 1: 2-5, preferably at 25-50 ° C, in the presence of 15-30% by weight of water. The reaction mixture was then treated with aqueous sodium hydroxide and the organic phase was diluted with 0.2-20% by weight of an aliphatic hydrocarbon solvent before distillation.

When practicing the process of the invention, the following operations may be carried out, as appropriate:

(1) recovering and recycling the aqueous ethylenediamine from the azeotrope to the reaction mixture, (2) recovering and returning the aliphatic hydrocarbon solvent to the reaction mixture, and (3) adding 10-100% by weight of the organic phase to the separated alkaline aqueous solution. phase, separating the extracted aqueous phase and diluting the organic phase with the hydrocarbon extract before fractional azeotropic distillation.

The process according to the invention has the advantage over the known processes that (1) the purity of the final product is greater than 99% by weight, (2) the product can be obtained in high yield, and (3) the process consists of a simple synthesis step.

According to the present invention, N-ethylene diamine having a purity greater than 99% by weight can also be prepared by: (a) ethylene diamine with ethyl halide (1-20): 1 molar ratio, -10-120 ° C; reacting under anhydrous reaction conditions;

(b) 0.2 to 30% by weight of the aliphatic hydrocarbon solvent is added to the resulting alkylated reaction mixture;

(c) fractionally distilling off the resulting reaction mixture of ethylene diamine and an aliphatic hydrocarbon solvent to remove ethylene diamine;

(d) adding at least 0.9 molar equivalents of sodium and / or potassium hydroxide per mole of ethyl halide to neutralize the reaction mixture;

(e) recovering the precipitated alkali halide precipitate from the slurry and recovering the mother liquor;

(f) washing the isolated alkali halide with an aliphatic hydrocarbon solvent;

(g) combining the mother liquor formed in step (e) and the aliphatic hydrocarbon washings recovered in step (f) and fractional distillation to remove ethylenediamine and water; and (h) fractionally distilling the resulting reaction mixture to remove residual aliphatic hydrocarbon solvent and recover the N-ethyl ethylenediamine.

Ethylenediamine, in the form of anhydrous or aqueous solution, and ethyl halide, preferably ethyl chloride, are prepared to form a reaction mixture containing from 1 to 20% by weight of water (preferably from 20 to 30% by weight): 0 to 50% by weight. ): 1] in a molar ratio with stirring and the reaction mixture is kept for 5-15 hours (preferably 7-9 hours) at 10-120 ° C (preferably 25-50 ° C). The ethyl halide may be ethyl chloride, ethyl bromide or ethyl iodide. The reaction time depends on the temperature used and at higher temperatures the reaction time may be shorter.

The reaction mixture is then mixed with an aqueous solution of an alkaline material to form a biphasic mixture of an organic phase and an alkaline aqueous phase with vigorous stirring. The alkaline material is used in an amount such that the pH of the aqueous phase is not less than 7, preferably less than 8. The alkali material may be sodium or potassium hydroxide or a mixture thereof, preferably a 50% w / w aqueous solution of sodium hydroxide.

After separation of the two phases, the aqueous phase is separated. The organic phase includes N-ethyl-ethylenediamine, unreacted ethylenediamine and polyalkylated products such as Ν, Ν'-diethyl ethylenediamine, N, N-diethylethylenediamine, Ν, Ν, Ν'-triethyl ethylene. -diamine and Ν, Ν, Ν ', Ν'-tetraethylethylenediamine. The aqueous phase is 1-3% by weight

-2182 922 ethylene diamine and 0.5-1% N-ethyl ethylenediamine. The organic phase is then diluted with an aliphatic hydrocarbon solvent of 10 to 100% by weight, preferably 10 to 20% by weight, of the organic phase.

Preferably, the separated aqueous phase is extracted with 10 to 100% by weight of the organic phase, preferably 10 to 20% by weight, of an aliphatic hydrocarbon solvent and the biphasic mixture is allowed to stand. After separation, the aqueous phase is separated and the extract obtained with the hydrocarbon solvent is used to dilute the above-mentioned organic phase.

Suitable aliphatic hydrocarbon solvents are those which are miscible with N-ethylethylenediamine, immiscible with ethylenediamine, and are azeotropic with water and / or ethylene diamine at a temperature of 128 to 131 ° C without significant amounts of The azeotrop would also contain N-ethyl-ethylenediamine. Such aliphatic hydrocarbon solvents include n-heptane, isooctane, cyclohexane, n-hexane, methylcyclohexane, n-pentane. etc Preferably n-heptane. Aromatic hydrocarbon solvents are not suitable because they are miscible with both ethylene diamine and N-ethylene diamine.

The diluted organic phase is then boiled in a distillation column to azeotropically fractionate the remaining ethylenediamine and water. After sedimentation of the distillate, the lower ethylenediamine water phase can be separated and recycled to the alkylator while the upper hydrocarbon phase can be recycled to the distillation device or used to extract the original biphasic mixture.

The remaining ethylene-diamine-free reaction mixture containing N-ethyl-ethylenediamine, multiple alkylated ethylenediamine diamines and an aliphatic hydrocarbon solvent is separated in a theoretical fractionating column in a fractional column to separate the aliphatic hydrocarbon solvent from N-ethylene diamine. For example, using a theoretical plate of 15 columns and using n-heptane as solvent, yields n-heptane as a precursor at 98-100 ° C. The hydrocarbon solvent distillate thus obtained can be traced back to other process steps, such as dilution of the organic phase, azeotropic removal of ethylenediamine and water from the reaction mixture, or extraction of the aqueous phase.

After removal of the hydrocarbon solvent distillate, the distillation was continued to yield N-ethyl-ethylenediamine (boiling point 130-131 ° C, purity greater than 99% by weight). In this way, N-ethylenediamine can be obtained in a yield of 63-65% based on ethyl halide.

The above process can also be used to separate water and / or ethylenediamine from N-ethylethylenediamine. In this case, an appropriate amount of a hydrocarbon solvent is added to the reaction mixture, the water and / or ethylenediamine is removed by fractional azeotropic distillation, and the remaining hydrocarbon solvent is fractionally distilled off. Anhydrous and ethylene-diamine-free N-ethyl-ethylenediamine is thus obtained. The above-described process can also be carried out continuously using suitable equipment, such as a distillation column, continuous flow reactors.

Alternatively, N-ethyl-ethylenediamine can be prepared by reacting liquid anhydrous ethylenediamine with ethyl halide according to Scheme (1) - X is chlorine, bromine, fluorine or iodine, preferably chlorine. The reaction mixture is stirred at -10 to 120 ° C, preferably 26 to 75 ° C for 1 to 24 hours, preferably 2 to 6 hours. The ethylenediamine is used in a molar ratio (1-20): 1, preferably (2-5): 1, relative to the ethyl halide. The reaction time depends on the temperature used, and at higher temperatures the reaction takes place sooner.

After the completion of the reaction, the reaction mixture is diluted with 0.2 to 30% by weight, preferably 0.5 to 1% by weight, of an aliphatic hydrocarbon solvent. The diluted reaction mixture is then boiled in a distillation column to remove unreacted ethylenediamine by fractional azeotropic distillation. The ethylenediamine distillate is preferably recovered and recycled.

Examples of aliphatic hydrocarbon solvents include n-heptane, isooctane, cyclohexane, n-hexane, methylcyclohexane, or n-pentane, preferably n-heptane.

The reaction mixture is then neutralized with at least 0.9 molar equivalent of alkaline material per mole of alkyl halide. As the alkaline substance, the substances described above, such as sodium or caustic hydroxide or mixtures thereof, may be used. Preferably, a 50% by weight aqueous solution of sodium hydroxide is used.

The alkali halide precipitate is isolated from the resulting slurry by known methods such as filtration or centrifugation and then washed with the aliphatic hydrocarbon solvents described above, preferably n-heptane.

The aliphatic hydrocarbon washings were collected and combined with the mother liquor obtained during the separation of the alkali halide precipitate. The combined liquids were subjected to fractional azeotropic distillation at atmospheric pressure on a packed column. Preferably, the heptane distillate is recycled to the top of the column until the residue is substantially anhydrous ethylene diamine.

The resulting reaction mixture, which is substantially free of ethylene diamine, containing N-ethyl ethylenediamine, poly (alkylated ethylene diamine) and an aliphatic hydrocarbon solvent, is suitable for separating the aliphatic hydrocarbon solvent from N-ethylene diamine. subjected to fractional distillation on a theoretical plate fractionated column. For example, using 15 theoretical plate columns, the n-heptane distillate distils at 98-100 ° C. The resulting hydrocarbon solvent distillate can be traced back to other steps of the process, such as diluting the reaction mixture or azeotropic distillation of the ethylenediamine and water from the reaction mixture.

After removal of the hydrocarbon solvent distillate, the reaction mixture is conveniently purged of impurities in the solution and then the clear solution is distilled. This gave N-ethyl-ethylenediamine, boiling point 130-131 C, purity greater than 99% by weight, in a yield of 62-65% based on ethyl halide.

The process described above can also be carried out continuously using suitable equipment, such as a continuous-flow reactor for a distillation column.

The invention is illustrated by the following examples, without limiting the scope of the invention to the examples. The purity of the product was determined by vapor chromatography (VPC).

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Example 1

This example illustrates the use of anhydrous ethylenediamine.

565 g (8.76 mol) of ethyl chloride are added to 1420 g (23.63 mol) of anhydrous ethylenediamine at 30-40 ° C for 5 hours. The reaction mixture was stirred for 2 hours and then treated with 50% w / w sodium hydroxide solution (935 mL, 17.5 mol). The resulting biphasic mixture was stirred for 30 minutes, then allowed to settle and the aqueous layer was separated and extracted twice with 150 ml of n-heptane. The heptane extracts are added to the organic phase and the combined solution is heated to distill ethylene diamine and water at 88-97 ° C as an azeotropic mixture; using a fractionation column and a separation device to recycle the distilled heptane from the distillation device and separate the dense aqueous ethylene diamine phase. In this way, an aqueous ethylene diamine phase containing 394 g of water and 896 g (14.91 mol) of ethylenediamine was separated. The ethylenediamine-free residue was fractionally distilled. This gives a heptane pre-concentrate (3-4 boiling point 98-102 ° C) containing 48% by weight of N-ethyl ethylenediamine and 484 g of N-ethyl ethylenediamine (boiling point 130-131 ° C). The purity of N-ethyl-ethylenediamine as determined by steam chromatography is greater than 99.8% by weight. The yield was 62.7% by weight based on ethyl chloride.

Example 2

The example illustrates the use of recovered aqueous ethylenediamine.

Ethyl chloride (545 g, 8.45 mol) was recovered at 12-40 ° C over 5 hours in 1245 g aqueous ethylene diamine (containing 14.39 mol ethylene diamine) and 550 g (9.23 mol). mole) to anhydrous ethylenediamine. The reaction mixture was then stirred for 2 hours and then 902 ml (16.9 mol) of 50% w / w sodium hydroxide was added. The resulting biphasic mixture was worked up as described in Example 1; the aqueous phase was extracted with n-heptane recovered in Example 1. By fractional distillation of the ethylene-diamine-free residue, a heptane concentrate containing 3 to 4% by weight of N-ethyl-ethylenediamine and 483 g of purity greater than 99.8% by weight of N-ethyl-ethylenediamine (boiling point) was obtained. 130-131 ° C). Yield 65% by weight based on ethyl chloride.

Example 3

The example illustrates the separation of ethylenediamine from N-ethylethylenediamine by azeotropic distillation.

A mixture of 500 g of ethylenediamine and 500 g of N-ethylethylenediamine was diluted with 200 ml of n-heptane and brought to reflux for fractional azeotropic distillation of ethylenediamine (boiling point 87-90 ° C). The above operation involves the use of a distillation column and a separation device which allows the recycled heptane to be recycled to the distillation device and to separate the thicker ethylenediamine phase. The ethylene diamine thus recovered contains less than 1% by weight of N-ethylethylenediamine (as determined by steam chromatography). The ethylene-diamine-free residue is then fractionally distilled to give a heptane pre-distillate and pure N-ethyl-ethylenediamine (b.p. 130-131 ° C).

Using cyclohexane, nhexane or isooctane as the solvent instead of n-heptane gives identical results.

Example 4

The example illustrates the separation of water from N-ethyl-ethylenediamine by azeotropic distillation.

To a mixture of 10 g of N-ethyl-ethylenediamine and 10 g of water is added 50 ml of n-heptane. The reaction mixture is heated to reflux and the water is removed by azeotropic fractionation (boiling point 88-98 ° C) using a distillation column and a separator which recycles the heptane into the distillation apparatus and separates the thicker aqueous phase. After removal of the water, the residue was fractionally distilled. In this way, N-ethyl-ethylenediamine (boiling point 130-31 ° C) containing heptane pre-distillate and less than 0.2% water is obtained.

By the same procedure, but using cyclohexane, n-hexane or isooctane as a solvent instead of n-heptane, similar results are obtained.

Example 5

To ethylene diamine (146.3 g, 2.43 mol) was added ethyl chloride (62.4 g, 0.967 mol) over 1 hour while allowing the reaction temperature to rise to 95 ° C. After completion of the addition of ethyl chloride, 34.2 g of n-heptane are added to the reaction mixture, and the resulting reaction mixture is subjected to azeotropic distillation on a fractionating column. The biphasic liquid distillate consisting of the lower ethylene diamine phase (85.09 g) and the upper heptane phase was collected in a Dean-Stark apparatus, the heptane phase recycled to the fractionation column, and the ethylene diamine removed.

The residue was cooled to 80 ° C, neutralized with 77.36 g (0.967 mol) of 50% w / w aqueous sodium hydroxide and the resulting sodium chloride precipitate was removed by filtration. This gives a slurry cake and a biphasic liquid filtrate. The slurry cake was washed with heptane (50 mL) and the washings were added to the original biphasic filtrate.

The resulting biphasic liquid is subjected to azeotropic distillation in a fractionating column. The biphasic distillate - containing n-heptane and water - is collected in a Dean-Stark apparatus. After removing all the water, the residue is fractionally distilled to remove heptane and recover the N-ethylenediamine. This gives 54.5 g of 99% pure N-ethyl-ethylenediamine. Boiling point 130-131 ° C. Yield: 64% by weight.

Example 6

The final distillation step was carried out as in Example 5. After complete removal of the water by azeotropic distillation, the residue was collected to separate the white precipitate (4.32 g). The filter cake was washed with 16 g of heptane and the washings were combined with the filtrate. The combined filtrate was washed once more and then fractionally distilled to remove heptane and recover N-ethyl-ethylenediamine. 53.7 g of 99% pure N-ethyl-ethylenediamine are thus obtained. Boiling point 130-131 ° C. Yield: 63% by weight.

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Example 7

To the glass-lined reactor was added 848 parts by weight of 98% by weight ethylene diamine (98%) followed by 331 parts by weight of liquid ethyl chloride at such a rate that the reaction temperature remained between 45 ° C and 55 ° C. The reaction mixture was stirred for 2 hours and then 91 parts by weight of heptane were added. Excess ethylenediamine is removed via a packed column by azeotropic distillation by returning the heptane distillate to the top of the column. 492 parts of ethylenediamine are recovered from the distillate. The reaction mixture was neutralized with 402 parts of 50% w / w sodium hydroxide solution, cooled to room temperature and centrifuged to remove the sodium chloride. The salt thus isolated is washed with 70 parts by weight of heptane and the washings are combined with the mother liquor in a glass lined device. Water from the pooled liquid is distilled on a packed column by azeotropic distillation, whereby the heptane distillate is recycled to the top of the column. After removing all the water, the heptane is fractionally distilled on a packed column. This gives 273 parts by weight of N-ethyl-ethylenediamine as a distillation residue. This residue is set aside and later on in Figures 8 to 10. Example 1 is combined.

Example 8

492 parts by weight of ethylene diamine recovered in Example 7 and 375 parts by weight of fresh 98% ethylene diamine were added to a glass-lined reactor. To the resulting mixture was added 331 parts by weight of ethyl chloride at such a rate that the reaction temperature was between 55 ° C and 65 ° C. After stirring for 2 hours, 45 parts by weight of the heptane recovered in Example 7 are added. Excess ethylenediamine in the packed column is distilled by azeotropic distillation while the heptane distillate is recycled to the top of the column. In this way, 501 parts by weight of ethylenediamine are recovered from the distillate. The reaction mixture was neutralized with 407 parts by weight of 50% sodium hydroxide solution, cooled to room temperature, and centrifuged to remove sodium chloride. The salt thus isolated is washed with 78 parts by weight of heptane and the washings are combined with the mother liquor in a glass lined device. Water from the combined liquid is distilled on a packed column by azeotropic distillation while the heptane distillate is recycled to the top of the column. After removing all the water, the heptane was fractionally distilled off on the packed column. The resulting residue contained 288 parts by weight of N-ethyl-ethylenediamine.

Example 9

501 parts by weight in a glass-lined reactor as in Example 8. ethylene diamine recovered and 396 parts fresh 98% ethylene diamine were added. To the resulting mixture was added 331 parts by weight of ethylene chloride at such a rate that the reaction temperature was between 65 ° C and 75 ° C. After stirring for 2 hours, 28 parts of heptane recovered in Example 8 are added. Excess ethylenediamine is distilled through a packed column by azeotropic distillation while the heptane distillate is recycled to the top of the column. In this way, 504 parts by weight of ethylenediamine are recovered. The reaction mixture was neutralized with 409 parts by weight of 50% sodium hydroxide solution, cooled to room temperature, and then centrifuged to remove sodium chloride. The salt thus isolated was washed with 82 parts by weight of heptane and the washings were combined with the mother liquor in a glass lined device. Water from the combined liquid is distilled on the packed column by azeotropic distillation while the heptane distillate is recycled to the top of the column. After removing all the water, the heptane was fractionally distilled off on the packed column. The resulting residue contains 310 parts by weight of N-ethylene diamine. This residue is discarded and subsequently combined with the remainder of Examples 7, 8 and 10.

Example 10

504 parts by weight of ethylene diamine recovered in Example 9 and 308 parts by weight of 98% fresh ethylene diamine are added to a glass-lined reactor. To the resulting mixture was added 331 parts by weight of ethyl chloride at such a rate that the reaction temperature was between 55 ° C and 65 ° C. The reaction mixture was stirred for 2 hours and then 30 parts by weight of heptane recovered in Example 9 were added. Excess ethylene diamine is distilled through a packed column by azeotropic distillation while the heptane distillate is recycled to the top of the column. In this way, 523 parts by weight of ethylenediamine are recovered. The reaction mixture was neutralized with 409 parts by weight of 50% sodium hydroxide solution, cooled to room temperature, and centrifuged to remove sodium chloride. The salt thus separated was washed with 91 parts by weight of heptane and the washings were combined with the mother liquor in a glass lined device. Water from the combined liquid is distilled on a packed column by azeotropic distillation while the heptane distillate is recycled to the top of the column. After removing all the water, the heptane was fractionally distilled off on the packed column. The resulting residue contains 317 parts by weight of N-ethyl-ethylenediamine, which is combined with the residue obtained in Examples 7, 8 and 9. The material thus obtained is fractionally distilled on the packed column at atmospheric pressure. In this way, 1120 parts by weight of N-ethyl-ethylenediamine were obtained. Boiling point 129-131 ° C. Yield 61.9% by weight, based on ethylene chloride.

Claims (10)

PATENT CLAIMS CLAIMS 1. A process for the preparation of N-ethylethylenediamine, characterized in that (a) ethylenediamine (1-20) is reacted with ethyl halide (II) in a molar ratio of 1 to 10 X And (b) neutralizing the resulting alkylated reaction mixture with 1 to 2 molar equivalents of an inorganic alkaline substance with respect to ethyl halide, (c) separating the aqueous phase from the neutralized organic phase, (d) optionally adding 10 to 100% by weight of the hydrocarbon solvent to the aqueous phase, separating the extracted aqueous phase and adding the hydrocarbon extract to the organic phase prior to fractional azeotropic distillation, (e) adding to the organic phase its own weight. 0.2 to 100% by weight of an aliphatic hydrocarbon solvent, -5182 922 (f) separating the water and ethylenediamine from the resulting mixture by fractional azeotropic distillation and optionally recycling it to step (a) or adding to the aqueous phase 10 to 100% by weight of a hydrocarbon solvent based on the weight of the organic phase, the extracted aqueous phase 5 is separated and the hydrocarbon extract is added to the organic phase before fractional azeotropic distillation, the aqueous phase being recycled to step (a). (g) fractionally distilling the resulting mixture, optionally recovering the hydrocarbon solvent from the distillate and returning it to the distillation mixture. (Priority: 30/01/1978) 2. A process according to claim 1, wherein the ethylenediamine (2-5) is reacted with ethyl halide at a temperature of 25-50 ° C in the presence of 15-30% by weight of water at a molar ratio of 1 to 2. aqueous sodium hydroxide solution and 0.2 to 20% by weight of an aliphatic hydrocarbon solvent is added to the organic phase. (Priority: 1978. 01/30) 3. A process according to claim 1 or 2 wherein the aliphatic hydrocarbon solvent is n-heptane. (Priority: 1978. 01/30) 4. A process for the preparation of N-ethyl-ethylenediamine, characterized in that (a) ethylene-diamine (1-20) is reacted with ethyl halide (II) in a molar ratio of (-10) -120 Under anhydrous conditions, (b) 0.2 to 3% by weight of a suitable aliphatic hydrocarbon solvent, (c) fractional distillation of ethylenediamine and the aliphatic hydrocarbon solvent, and (d) the resulting reaction mixture. Neutralizing with at least 0.9 molar equivalents of the corresponding alkaline material per mole of ethyl halide, (e) separating the precipitate of alkali halide from the resulting slurry and recovering the resulting mother liquor, (f) washing the separated alkali halide with aliphatic g) combining the mother liquor of step (e) and the aliphatic hydrocarbon washer fluid of step (f) and fractionate the resulting mixture and (h) subjecting the resulting reaction mixture to further fractionation. (Priority: November 15, 1978) 5. The process of claim 4 wherein the aliphatic hydrocarbon solvent is n-heptane. (Priority; November 15, 1978) 6. The process of claim 4, wherein step (a) is carried out at 25-75 ° C. (Priority: November 15, 1978) 7. The process of claim 4, wherein the ethylene 20 diamine and ethyl halide (2-5) are used in step (a) in a molar ratio of 2 to 5. (Priority: November 15, 1978) 8. The process according to claim 4, wherein in step (b) the reaction mixture is present in an amount of 0.5 to 1.0% by weight based on the weight of the reaction mixture. 25 aliphatic hydrocarbon solvents were added. (Priority: 11/15/1978) 9. The process according to claim 5, wherein the amount of n-heptane in step (b) is 0.5 to 1.0% by weight, based on the weight of the reaction mixture. (Priority: November 15, 1978) 10. The process according to claim 4, wherein the alkaline material in step (b) is 50% by weight aqueous sodium hydroxide. 35 applied. (Priority: November 15, 1978)