CN111153814B

CN111153814B - Synthesis method of N-N-butylethanolamine

Info

Publication number: CN111153814B
Application number: CN202010041970.1A
Authority: CN
Inventors: 刘杰; 欧阳佳龙; 孔超
Original assignee: Hubei Chuang Chuang Biological Technology Co ltd
Current assignee: Hubei Chuang Chuang Biological Technology Co ltd
Priority date: 2020-01-15
Filing date: 2020-01-15
Publication date: 2023-04-21
Anticipated expiration: 2040-01-15
Also published as: CN111153814A

Abstract

The invention discloses a synthesis method of N-N-butyl ethanolamine, which comprises the following steps: completing the installation of the synthesis device; n-butylamine is added into the four-neck flask, air is replaced by nitrogen, and then vacuum is pumped; heating through an electric heating sleeve, then starting a circulating pump, opening an ethylene oxide valve, and introducing ethylene oxide in an ethylene oxide container into a four-neck flask for reaction; terminating the reaction immediately when no increase of the product is detected, and cooling to room temperature; and transferring the finally generated material into a rectifying column, recovering N-butylamine at normal pressure, and rectifying in vacuum to obtain N-N-butylethanolamine. According to the invention, the N-N-butyl ethanolamine is synthesized by adopting the ethylene oxide and the N-butyl amine, so that the yield of the N-N-butyl ethanolamine is effectively improved, the synthesis cost of the N-N-butyl ethanolamine is reduced, the ethylene oxide and the N-butyl amine are low in price, and are addition reactions, so that the atomic economic benefit is high, and other solvents are not needed.

Description

Synthesis method of N-N-butylethanolamine

Technical Field

The invention belongs to the field of compound synthesis, and particularly relates to a synthesis method of N-N-butylethanolamine.

Background

N-N-butylethanolamine and N, N-di-N-butylethanolamine are two important fine chemical intermediates, have wide application in textile, medicine, agricultural chemicals and the like, can be used for producing medicines, coatings, surfactants and the like, and can also be used as decarburization, desulfurizing agents and the like. In recent years, N-N-butyl ethanolamine is developed and utilized as an auxiliary agent component and a paint regulator of a metal cutting fluid, and with the rapid development of the Chinese industrial processing and building industry, the market demand of N-N-butyl ethanolamine is rapidly expanded. Therefore, how to increase the yield of N-butylethanolamine and how to reduce the synthesis cost of N-butylethanolamine is a technical problem to be solved.

Disclosure of Invention

The invention aims to overcome the problems existing in the prior art and provide a method for synthesizing N-N-butylethanolamine.

In order to achieve the technical purpose and the technical effect, the invention is realized by the following technical scheme:

a method for synthesizing N-N-butylethanolamine, comprising the following steps:

step one: and (3) finishing the installation of the synthesis device: firstly, placing a four-mouth flask in an electric heating sleeve, installing a magnetic stirrer at the bottom of the electric heating sleeve, respectively connecting the four-mouth flask with a thermometer, a rectifying column, an air duct and a return pipe, wherein the top end of the rectifying column is provided with a condensing pipe which is communicated with the return pipe through a circulating pump, a pressure gauge is arranged between the condensing pipe and the circulating pump, and the air duct is connected with an ethylene oxide container through an ethylene oxide valve;

step two: n-butylamine is added into the four-neck flask, air is replaced by nitrogen, and then vacuum is pumped;

step three: heating through an electric heating sleeve, then starting a circulating pump, opening an ethylene oxide valve, and introducing ethylene oxide in an ethylene oxide container into a four-neck flask for reaction;

step four: terminating the reaction immediately when no increase of the product is detected, and cooling to room temperature;

step five: and transferring the finally generated material into a rectifying column, recovering N-butylamine at normal pressure, and rectifying in vacuum to obtain N-N-butylethanolamine.

Further, the molar ratio of the n-butylamine to the ethylene oxide is 1:1.6-1.8.

Further, in the step three, the ethylene oxide is introduced slowly at a constant speed and the introduction time is controlled to be 5-6 hours.

Further, the reaction pressure of the n-butylamine and the ethylene oxide is 0.05 MPa-0.06 MPa.

Further, the initial temperature of the reaction of the n-butylamine and the ethylene oxide is controlled at 78 ℃, and the final temperature is controlled at 134-140 ℃.

The beneficial effects of the invention are as follows:

according to the invention, the N-N-butyl ethanolamine is synthesized by adopting the ethylene oxide and the N-butylamine, so that the yield of the N-N-butyl ethanolamine is effectively improved, the synthesis cost of the N-N-butyl ethanolamine is reduced, the ethylene oxide and the N-butylamine are low in price, the ethylene oxide and the N-butylamine are in addition reaction, the atomic economic benefit is high, other solvents are not needed, and the cost can be obviously reduced as long as the yield of the N, N-di-N-butyl ethanolamine is controlled; the production process of cyclic reaction and separation while reaction is adopted, reaction products are removed in time, and the generation amount of N, N-di-N-butyl ethanolamine is effectively inhibited, so that the purposes of high yield and low cost of the N-N-butyl ethanolamine are achieved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and together with the description serve to explain the invention and do not constitute a limitation on the invention. In the drawings:

FIG. 1 is a schematic diagram of a synthesizing apparatus according to the present invention;

FIG. 2 is a schematic representation of the conversion of n-butylamine as a function of product selectivity in the present invention;

FIG. 3 is a schematic representation of ethylene oxide feed rate versus product selectivity in accordance with the present invention;

FIG. 4 is a graphical representation of reaction pressure versus product selectivity in the present invention.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The synthesis method of the N-N-butylethanolamine shown in the figure 1 comprises the following steps:

step one: and (3) finishing the installation of the synthesis device: firstly, a four-neck flask 3 is placed in an electric heating sleeve 2, a magnetic stirrer 1 is arranged at the bottom of the electric heating sleeve 2, the four-neck flask 3 is respectively connected with a thermometer 10, a rectifying column 4, an air duct 12 and a return pipe 11, a condensing pipe 5 is arranged at the top end of the rectifying column 4, the condensing pipe 5 is communicated with the return pipe 11 through a circulating pump 7, a pressure gauge 6 is arranged between the condensing pipe 5 and the circulating pump 7, and the air duct 12 is connected with an ethylene oxide container 8 through an ethylene oxide valve 9;

step two: n-butylamine is added into the four-neck flask 3, air is replaced by nitrogen, and then vacuum is pumped;

step three: heating through the electric heating sleeve 2, then starting the circulating pump 7, opening the ethylene oxide valve 9, and introducing ethylene oxide in the ethylene oxide container 8 into the four-neck flask 3 for reaction;

step five: and transferring the finally generated material into a rectifying column 4, recovering N-butylamine at normal pressure, rectifying in vacuum to obtain N-N-butylethanolamine, merging the N, N-di-N-butylethanolamine with high boiling point for multiple times, and rectifying again for recovery.

As can be seen from FIG. 2, as the addition amount of N-butylamine increases, the conversion rate of N-butylamine is lower and the selectivity of N-N-butylethanolamine is gradually improved, and the recovery cost of N-butylamine is comprehensively considered, and the molar ratio of N-butylamine to ethylene oxide is preferably controlled to be 1:1.6-1.8.

As can be seen from fig. 3, the ethylene oxide feeding speed is a main factor affecting the reaction, the actual feeding speed reflects the molar ratio of n-butylamine to ethylene oxide in the reaction region, the feeding speed is too high, the ethylene oxide content in the reaction region is too high, the molar ratio of n-butylamine to ethylene oxide in the region is low, the byproduct is increased, and the product selectivity is poor; the feeding speed is too slow, the selectivity of the product is not increased much and the product tends to be stable, but the energy consumption is increased, which is unfavorable for the control of the production cost, so that the ethylene oxide is fed slowly at a constant speed and is controlled to be fed for 5-6 hours.

As can be seen from FIG. 4, the reaction pressure is low, the product selectivity is poor, the reaction pressure is too high, the requirements on equipment are also high, and the energy consumption cost is correspondingly increased, so that the optimal reaction pressure of n-butylamine and ethylene oxide is 0.05-0.06 MPa.

In order to keep proper gasification amount of the n-butylamine, the reaction starting temperature of the n-butylamine and the ethylene oxide is controlled at 78 ℃ gradually in the reaction process, and the product is more and more along with the progress of the reaction, and the boiling point of the product is 198 ℃, so that the temperature of materials in the kettle must be increased gradually to ensure the gasification amount of the n-butylamine, and the final temperature is controlled at 134-140 ℃, thereby the ethylene oxide is fully converted under the condition of ensuring the gasification amount.

The foregoing has shown and described the basic principles, principal features and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present invention, and various changes and modifications may be made without departing from the spirit and scope of the invention, which is defined in the appended claims.

Claims

1. A synthesis method of N-N-butylethanolamine is characterized in that: the synthesis method comprises the following steps:

step one: and (3) finishing the installation of the synthesis device: firstly, placing a four-neck flask (3) in an electric heating sleeve (2), installing a magnetic stirrer (1) at the bottom of the electric heating sleeve (2), respectively connecting the four-neck flask (3) with a thermometer (10), a rectifying column (4), an air duct (12) and a return pipe (11), wherein a condensing pipe (5) is installed and connected at the top end of the rectifying column (4), the condensing pipe (5) is communicated with the return pipe (11) through a circulating pump (7), a pressure gauge (6) is installed between the condensing pipe (5) and the circulating pump (7), and the air duct (12) is connected with an ethylene oxide container (8) through an ethylene oxide valve (9);

step two: n-butylamine is added into the four-neck flask (3), air is replaced by nitrogen, and then vacuum is pumped;

step three: heating through an electric heating sleeve (2), then starting a circulating pump (7), opening an ethylene oxide valve (9), and introducing ethylene oxide in an ethylene oxide container (8) into a four-neck flask (3) for reaction;

step five: and transferring the finally generated material into a rectifying column (4), recovering N-butylamine at normal pressure, and then rectifying in vacuum to obtain N-N-butylethanolamine.

2. The method for synthesizing N-N-butylethanolamine according to claim 1, wherein the method comprises the following steps: the mol ratio of the n-butylamine to the ethylene oxide is 1:1.6-1.8.

3. The method for synthesizing N-N-butylethanolamine according to claim 1, wherein the method comprises the following steps: and in the step three, the ethylene oxide is introduced slowly at a constant speed and the introduction time is controlled to be 5-6 hours.

4. The method for synthesizing N-N-butylethanolamine according to claim 1, wherein the method comprises the following steps: the reaction pressure of the n-butylamine and the ethylene oxide is 0.05 MPa-0.06 MPa.

5. The method for synthesizing N-N-butylethanolamine according to claim 1, wherein the method comprises the following steps: the initial temperature of the reaction of the n-butylamine and the ethylene oxide is controlled at 78 ℃, and the final temperature is controlled at 134-140 ℃.