JPS6128658B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing bis[β-(N,N-dimethylamino)ethyl]ether. More specifically, a bismethhalide compound of bis[β-(N,N-dimethylamino)ethyl]ether ( X is a halogen atom, hereinafter abbreviated as bismethhalide. ) and an aliphatic amine having active hydrogen to form bis[β-(N,N-dimethylamino)
The present invention relates to a method for industrially producing ether amine by repeatedly reusing the aliphatic amine recovered from the reaction solution when producing ethyl]ether (hereinafter abbreviated as ether amine). A method for producing the corresponding ether amine by demethylation reaction of the bismethohalide is disclosed in US Pat. No. 3,400,157 and Japanese Patent Publication No. 7411/1983. Japanese Patent Publication No. 48-7411 discloses a method for producing an ether amine by subjecting the bismethohalide to a demethylation reaction in the presence of a high-boiling polyamine having a primary amino group with a boiling point of 220° C. or higher. The publication states that the amount of high boiling point polyamines such as aminoethylethanolamine and triethylenetetramine required to produce 1 kg of the desired ether amine is:
Although it is stated that 2.3 to 3.5 kg is also required,
It is extremely disadvantageous economically to use large amounts of these expensive polyamines. When producing an ether amine by reacting an aliphatic amine having a boiling point of 40 to 170°C under atmospheric pressure with the bismethhalide, the present inventors used the aliphatic amine as a demethylating agent after the reaction. A patent application has already been filed for a method to collect and use it repeatedly. That is, after the reaction, an alkaline compound in an amount necessary to neutralize the hydrochloric acid is added to the reaction mixture consisting of the hydrochloride of the amine, and the amines are completely liberated. After neutralization, water is distilled off from the mixture mainly consisting of amines, water and salt. After removing the precipitated salt by centrifugation, the liquid is distilled to separate and recover the aliphatic amine from the ether amine. By repeatedly using the aliphatic amine recovered by such a method, the economic efficiency of the ether amine manufacturing process is improved. However, the aliphatic amine recovery method described above is an extremely complicated separation and recovery method that involves multi-stage separation operations of distillation, centrifugation, and distillation of the reaction solution after neutralization. What is important in the process of recovering and reusing aliphatic amines as demethylating agents is the salt produced by neutralization, the raw material bismethhalide, and the water brought into the reaction system together with the recovered aliphatic amine, as well as the neutralization. The objective is to efficiently remove salts such as water generated by the reaction, water, and other substances that have an unfavorable effect on the reaction from the aliphatic amine by a simple method. If the aliphatic amine used does not form an azeotrope with water, as described above, water is selectively removed from the neutralized reaction solution by distillation, and the aliphatic amine is further removed by desalting and distillation. It is possible to recover the amine. However, when an aliphatic amine that forms an azeotrope with water, such as ethylenediamine, is used as a demethylating agent, water cannot be selectively removed by normal atmospheric distillation. That is, depending on the type of aliphatic amine, it is difficult to separate the aliphatic amine from water or salt by a method consisting of a series of operations of distillation dehydration, centrifugation desalination, and distillation recovery as described above. The raw material bismethohalide is heated at 40 to 170℃ under atmospheric pressure.
In the process for producing ether amines, the aliphatic amines are reacted with aliphatic amines having a boiling point of There is a strong desire for extremely simple separation and recovery of aliphatic amines, which can be universally applied regardless of the type of aliphatic amine and regardless of the chemical structure of the aliphatic amine used as a demethylating agent. In view of these circumstances, the present inventors have conducted intensive research, and as a result, the present inventors added an alkali metal hydroxide to a reaction solution of a bismethohalide and an aliphatic amine having active hydrogen derived from an amino group for treatment. We have discovered an extremely simplified post-reaction treatment method that can neutralize, desalt, and dehydrate the reaction solution simultaneously and rapidly by performing a substantially single operation consisting of the above-mentioned steps. The liquid treated by this method is crudely distilled, and the distillate, which has a boiling point of 170°C or lower and mainly contains aliphatic amines and various organic substances, is separated and recovered from the ether amine and repeatedly reused as a demethylating agent. The present inventors have discovered a new fact that ether amines can be produced in high yield even when the ether amines are used, and have completed the present invention. The present invention is based on the general formula (X is a halogen atom) bis[β-
(N,N-dimethylamino)ethyl] ether bismethhalide compound and aliphatic amine having a boiling point of 40 to 170°C under atmospheric pressure and having 1 to 2 primary amino groups in the molecule When producing bis[β-(N,N-dimethylamino)ethyl]ether by reaction with (a) after the reaction between the bismethhalide compound and the aliphatic amine, the amount of water in the reaction system (b) Separate and recover the liquid phase consisting of amines, (c) Boil the recovered amines at atmospheric pressure.
Distillation separation into fractions below 170℃ and fractions above 170℃, (d)
Provided is a method for producing bis[β-(N,N-dimethylamino)ethyl]ether, characterized in that recovered amines having a boiling point of 170°C or less at atmospheric pressure are reused for the reaction with the bismethohalide. It is something. The raw material bismethohalide used in the present invention is represented by the following general formula. (X is a halogen atom) That is, bis[β-(N,N-dimethylamino)
Ethyl] ether bismethhalide compound,
Among these bismethohalides, bismethochloride and bismethobromide are widely used as raw materials due to economic efficiency and availability of raw materials. The aliphatic amine used in the present invention is
It is an aliphatic amine having a boiling point of 40 to 170°C and having 1 to 2 primary amino groups in the molecule. Specific examples of typical compounds include n-propylamine, butylamine, ethylenediamine, propanediamine, butanediamine, and the like. In particular, ethylenediamine and propanediamine are used as extremely useful aliphatic amines in the production process of the present invention because they have excellent ether amine production capacity per unit weight of amine and are easy to use. The ether amine production process in the present invention basically involves the step of reacting a raw material bismethohalide with an aliphatic amine as a demethylating agent, and aliphatic amine to be reused as a demethylating agent from the reaction solution. The process consists of separating and collecting the
Although the reaction method in the reaction step is not particularly limited, it is usually carried out by the method shown below. That is, the reaction between the bismethohalide and the aliphatic amine is carried out at a temperature of 100 to 190°C under normal pressure or increased pressure. When an aliphatic amine having a relatively low boiling point is used, the reaction is carried out under pressure and at an elevated temperature in order to prevent the aliphatic amine from escaping out of the reaction system. Furthermore, when an aliphatic amine having a relatively high boiling point is used, the reaction may be carried out under reflux cooling at normal pressure. The amount of aliphatic amine added is usually 2 to 1 mole of the bismethohalide.
Can be added in moles or more. The upper limit of the amount of aliphatic amine added is not particularly limited, but an efficient amount is selected in consideration of the production efficiency of the reactor and the recovery burden associated with the amount of aliphatic amine recovered after use. . The aliphatic amine not only acts as a demethylation agent for the bismethhalide, but also functions as a diluting and dispersing agent for improving the dispersibility of the bismethhalide. Therefore, it is not necessarily necessary to newly add a diluting dispersant such as an organic solvent to the reaction system. As described in Japanese Patent Publication No. 48-7411, the reaction is generally carried out in a non-aqueous system using an aliphatic amine as a diluting and dispersing agent, or in a system in which glycol ethers are added as a diluent. be. Since water is used as a solvent in the process of producing the raw material bismethohalide, the water accompanying the raw material is introduced into the reaction system of this process. There is no problem in carrying out the reaction in a system using as a diluent. The use of diluents such as water is not particularly advantageous in terms of ether amine yield and reactor efficiency;
The amount added is preferably equal parts by weight or less based on the bismethhalide. In order to industrially produce ether amines,
It is important to recover the aliphatic amine from the reaction solution obtained by the above-mentioned reaction and use it repeatedly in the reaction to improve the economic efficiency of the process. The method for separating and recovering aliphatic amines based on the present invention is as follows:
It consists of performing the following processing. That is, the reaction solution of the raw material bismethohalide and the aliphatic amine accepts the methyl group from the generated ether amine and bismethhalide, and reacts with the partially structurally modified aliphatic amine mixture and the raw material. It consists of water, hydrohalic acid, various side reaction products, etc. brought into the system. An alkali metal hydroxide is added to this reaction solution, and the hydrohalic acid is first neutralized to generate free amines. Next, the alkali metal hydroxide concentration is 10 to 55% by weight, preferably 20 to 52% by weight, based on the amount of water in the liquid.
Alkali metal hydroxide is added to give a weight percent. The reaction mixture treated in this way is separated into a slurry-like solid phase containing precipitated solids such as neutral salts and a liquid phase mainly consisting of free amines. A liquid phase consisting of amines is separated and recovered from the solid-liquid phase thus obtained. Furthermore, the recovered amines are separated by distillation into a distillate with a boiling point of 170°C or lower (under atmospheric pressure) and an ether amine, which is a distillate with a boiling point above 170°C. Ether amine is a product,
The recovered amines, which mainly consist of the aliphatic amine mixture and have a boiling point of 170° C. or lower, can be reused as they are for the reaction with the bismethohalide compound without being rectified. The alkali metal hydroxide used in the present invention is
Although not particularly limited, sodium hydroxide or potassium hydroxide is usually used in the form of a solid or an aqueous solution. In order to minimize the amount of water introduced into the system, it is preferable to use solid alkali metal hydroxides. After neutralization, the concentration of alkali metal hydroxide that is further added is defined as follows. Alkali metal hydroxide concentration = C/A+B+C×100% A: Amount of water in the reaction solution before neutralization reaction B: Amount of water produced by neutralization reaction C: Alkali metal hydroxide present in the system If the alkali metal hydroxide concentration in the system is less than 10% by weight, dehydration from the reaction solution will not be sufficient, and the distillate with a boiling point of 170°C or less recovered under these conditions will be treated as bismethhalide. When used repeatedly for reactions with ether amines, the amount of water in the reaction system accumulates and increases, leading to a decrease in reactor utilization efficiency and further to a decrease in ether amine yield. Furthermore, desalination is not sufficient, and when the alkali metal hydroxide treated solution is crudely distilled, salt remains in the still and causes corrosion. Even if the alkali metal hydroxide is added to a concentration of 55% by weight or more, it will only result in economic loss due to excessive addition of the alkali metal hydroxide. The operating conditions for adding the alkali metal hydroxide to the reaction solution and performing the stirring treatment are not particularly limited, but the following conditions are preferably selected. That is, the treatment temperature is operated at a temperature above 20°C and below the boiling point of the aliphatic amine, preferably at a temperature of 40 to 120°C. The higher the treatment temperature, the shorter the time required for the treatment to be completed and the more efficient the reaction solution can be treated. When the treatment is carried out in a temperature range of 40 to 120°C, the treatment is usually completed in 0.5 to 5 hours, and a slurry-like solid phase containing neutral salts etc. begins to settle. After standing still, by separating the supernatant liquid phase from the solid phase,
A desalted and dehydrated liquid consisting mainly of ether amine and the aliphatic amine mixture can be recovered. This separation and recovery method can be carried out by, for example, sucking up the supernatant liquid after allowing it to stand still, filtering it by adding a filter or the like, or centrifuging it. When distilling the recovered amines to obtain the product ether amine (boiling point 190°C/760mmHg), a pre-distillate mainly consisting of the aliphatic amine mixture with a boiling point of 170°C or lower under atmospheric pressure is collected and reused as a bismethhalide. used in reactions with Distillation conditions are not particularly limited, and the distillation may be carried out under normal pressure, reduced pressure or increased pressure, but it is usually carried out under normal pressure or reduced pressure. When distilling the treated liquid, only the boiling point fraction of the aliphatic amine mixture may be recovered by rectification and reused for the reaction with the bismethhalide, but this is not particularly advantageous in terms of equipment and labor. . Basically, the treatment liquid is an ether amine fraction,
A simplified distillation operation in which the ether amine is separated by distillation from a fraction consisting of other compositions and the fraction other than the ether amine is reused for the reaction with the bismethhalide is sufficient. As mentioned above, the aliphatic amine mixture recovered by a very simplified separation operation consisting of a combination of alkali metal hydroxide treatment of the ether amine production reaction solution and crude distillation operation is used as a demethylating agent. The ether amine production process of the present invention, which can be used repeatedly, not only greatly improves operability, but also does not require special equipment.In other words, industrial production of ether amines can be performed using general-purpose equipment, and the equipment It can be said that it is an extremely useful method from this point of view. Further, even if the distillate containing the aliphatic amine mixture recovered by the method according to the present invention is repeatedly used for reaction with the bismethhalide compound, ether amines can be produced in high yield. The method according to the present invention can be said to be an economically extremely superior industrial method for producing bis[β-(N,N-dimethylamino)ethyl]ether. The present invention will be explained below with reference to Examples, but the present invention is not particularly limited by these. Example 1 Production of bismethochloride of bis[β-(N,N-dimethylamino)ethyl]ether 2820 g of a 30% aqueous trimethylamine solution (846 g of trimethylamine) and bis[β-chloroethyl] were placed in a stainless steel electromagnetic stirring autoclave (No. 5).
860 g of ether was charged, heated to 70°C, and reacted for 6 hours. After the reaction, excess unreacted trimethylamine was purged and the reaction solution was analyzed.
Quantitative analysis of chloride ions by Forhardt's method revealed that the amount was 12.0 equivalents (theoretical amount: 12.02 equivalents). ¹ H-NMR and ¹³ C-NMR analysis of the reaction solution revealed that the product was bismethochloride of bis[β-(N,N-dimethylamino)ethyl]ether, which was produced almost quantitatively. It could be confirmed. Production of bis[β-(N,N-dimethylamino)ethyl]ether 5. In a stainless steel electromagnetic stirring autoclave, add a 70% aqueous solution of bismethchloride of bis[β-(N,N-dimethylamino)ethyl]ether.
1258g (880.6g of bismethochloride) and 1416g of ethylenediamine were charged, and the reaction temperature was 155℃.
The reaction was carried out for 5 hours at a reaction pressure of 2.5 to 3.5 kg/cm ² . After cooling, the reaction solution was taken out and transferred to a four-necked glass flask equipped with a stirrer, a thermometer insertion tube, and a reflux condenser. Next, 694 g of solid sodium hydroxide was added, and the mixture was stirred at a temperature of 50 to 60° C. for 2.5 hours. 2150g of supernatant liquid from the solid phase that settled in the lower layer
was separated and collected and transferred to a distillation vessel. Column height 50
The supernatant recovered liquid was subjected to normal pressure distillation in a distillation column of cm (glass Laschich ring packing) to obtain 1655 g of distillate (fraction -) with a column top temperature of 90 to 125°C. As a result of gas chromatography analysis, ethylenediamine and N-ethylated ethylenediamine (hereinafter abbreviated as ethylenediamine modified product) 1480
The existence of g was confirmed. Next, vacuum distillation is performed and the column top temperature is 132℃.
(165 mmHg) 456 g (distillate) of distillate liquid was obtained. As a result of gas chromatography analysis, the fraction -
was confirmed to be bis[β-(N,N-dimethylamino)ethyl]ether. 1655 g of the distillate was used as it was in the second ether amine production reaction. A similar separation and recovery operation was performed, and the reaction was repeated three times under the same conditions as the first time. Only the recovered ethylenediamine modified mixture was used repeatedly without adding new ethylenediamine. The results are shown in Table 1.

[Table] Example 2 Bis[β-(N,N
-dimethylamino)ethyl]ether 1300 g of a 73% aqueous solution of bismethochloride (949 g of bismethochloride) and 1884 g of 1,3-propanediamine
and reaction temperature of 150℃, reaction pressure of 2 to 3 kg/
The reaction was carried out at cm ² for 7 hours. After the reaction, the reactor was cooled, the reactor lid was opened, 620 g of solid sodium hydroxide was added, the lid was closed again, and the mixture was heated and stirred at 70 to 90°C for 2 hours. 2710 g of supernatant liquid was separated and collected from the lower solid phase. Using the same distillation column as in Example 1, the supernatant recovered liquid was distilled at normal pressure, and the top temperature of the column was 90 -
2108 g of distillate (distillate -) at 148°C was obtained. As a result of gas chromatography analysis, the presence of 1920 g of propanediamine and N-methylated propanediamines (hereinafter abbreviated as propanediamine modified product) was confirmed. Subsequently, vacuum distillation was performed to obtain 513 g of distillate with a column top temperature of 132°C (160 mmHg).
(Fraction -) was obtained. As a result of gas chromatographic analysis, 509 g of bis[β-(N,N-dimethylamino)ethyl]ether was confirmed in the fraction. 2108 g of the fraction was used as it was in the second ether amine production reaction. Similar separation and recovery operations were carried out and the reaction was repeated four times. Propanediamine was not newly added, and only the recovered propanediamine modified mixture was repeatedly used.
The results are shown in Table 2.

[Table] Comparative Example 1 Bis[β-(N,N
1000 g of a 70% aqueous solution of bismethochloride (700 g of bismethochloride) of -dimethylamino)ethyl ether and 1300 g of ethylenediamine were charged, and the reaction was carried out for 7 hours at a reaction temperature of 150°C and a reaction pressure of 2.5 to 3.5 Kg/ ^cm2. Summer. After the reaction, 249g of solid sodium hydroxide was added in the same manner as in Example 1, and the temperature was increased to 70~
The mixture was heated and stirred at 80°C for 3 hours. After standing still, supernatant liquid
2173g was separated and recovered from the lower solid phase. Example 1
Perform atmospheric pressure distillation of the supernatant recovered liquid using the same distillation column as above, and obtain a distillate with a column top temperature of 90 to 127℃.
1785g (fraction) was obtained. As a result of gas chromatography analysis, the presence of 1360 g of a mixture of ethylenediamine and N-methylated ethylenediamine was confirmed. Next, vacuum distillation is performed to raise the column top temperature.
367g of distillate at 127-132℃ (160mmHg)
) was obtained. As a result of gas chromatography analysis, 363 g of bis[β-(N,N-dimethylamino)ethyl]ether was confirmed in the distillate. 1785 g of the fraction was used as it was in the second ether amine production reaction. The same reaction was repeated three times. The results are shown in Table 3.

【table】

Claims (1)

[Claims] 1. General formula (X is a halogen atom) bis[β-
(N,N-dimethylamino)ethyl]ether bismethhalide compound and 40-170℃ under atmospheric pressure
When producing bis[β-(N,N-dimethylamino)ethyl]ether by reaction with an aliphatic amine having a boiling point of 1 to 2 primary amino groups in the molecule, (a) After the reaction between the bismethohalide compound and the aliphatic amine is completed, an alkali metal hydroxide is added to the amount of 10 to 55% by weight based on the amount of water in the reaction system, and (b) the amine is (c) The recovered amines have a boiling point of 170°C or lower at atmospheric pressure.
(d) Recovered amines with a boiling point of 170°C or less at atmospheric pressure are separated by distillation into fractions exceeding 170°C.
A method for producing bis[β-(N,N-dimethylamino)ethyl]ether, characterized in that it is reused in the reaction with the bismethohalide. 2. The manufacturing method according to claim 1, wherein the aliphatic amine is propylamine, butylamine, ethylenediamine, propanediamine or butanediamine. 3. The manufacturing method according to claim 1, wherein the alkali metal hydroxide is sodium hydroxide or potassium hydroxide.