CN217248859U

CN217248859U - Preparation system of electronic grade N-methylformamide

Info

Publication number: CN217248859U
Application number: CN202221201805.9U
Authority: CN
Inventors: 陈峰华; 刘立新
Original assignee: Beijing Xinmeige Engineering Design Co ltd
Current assignee: Beijing Xinmeige Engineering Design Co ltd
Priority date: 2022-05-19
Filing date: 2022-05-19
Publication date: 2022-08-23
Anticipated expiration: 2032-05-19

Abstract

The utility model discloses a preparation system of electron-level N-methylformamide, include: the device comprises a methyl formate reactor and an amination reactor which are connected with each other, wherein the amination reactor is connected with a product refining unit and is used for purifying and refining the obtained N-methylformamide to obtain electronic-grade N-methylformamide; the methyl formate reactor is communicated with a carbon monoxide purification unit through a pipeline, CO purified by the carbon monoxide purification unit enters the methyl formate reactor to perform esterification reaction, and the carbon monoxide purification unit comprises two adsorption towers connected in parallel. The utility model discloses a preparation system adopts CO and methyl formate of methyl alcohol oxo synthesis earlier, and reuse methyl formate makes N-methylformamide with the synthesis of monomethylamine, and through the purification refining to the purification of raw materials and the purification refining of product in the whole technology, finally obtains electron level N-methylformamide.

Description

Preparation system of electron-grade N-methylformamide

Technical Field

The utility model relates to a preparation field of electron level N-methylformamide especially relates to a preparation system of electron level N-methylformamide.

Background

N-methylformamide is an important organic chemical raw material and intermediate, is an organic solvent with better performance, and is also used as a reaction solvent and a refining solvent for organic synthesis. The N-methylformamide is used for synthesizing high-efficiency low-toxicity single-cimetidine and double-cimetidine as pesticide and acaricide. N-methylformamide is also widely used in the production of medicines, synthetic leather, dyes, perfumes, artificial leather, electrolysis and electroplating industries, fiber textile solvents and the like.

At present, in the electronic industry, for example, N-methyl pyrrolidone is mainly used as an alignment agent coated on a liquid crystal display, liquid crystal display manufacturers are gradually replacing the liquid crystal display with N-methyl formamide products, the use functions and the effects are equivalent, and the cost is greatly reduced compared with the cost of N-methyl pyrrolidone. Due to the large market sales of liquid crystal display series products, the demand of the future market for N-methylformamide is expected to increase further.

The N-methylformamide is used for liquid crystal displays, has high requirements on the quality of commodities and needs to meet the requirements of electronic grade. However, the prior domestic N-methylformamide production technology mainly adopts an intermittent method, has low production efficiency, unstable raw material quality and low product quality, and cannot meet the requirement of electronic grade.

In view of this, the utility model discloses it is special.

SUMMERY OF THE UTILITY MODEL

Problem to prior art exists, the utility model aims to provide a preparation system of electron level N-methylformamide, through the utility model discloses a system adopts CO and methyl alcohol oxo synthesis methyl formate earlier, and reuse methyl formate makes N-methylformamide with the synthesis of monomethylamine, and through the purification of the purification refining of raw materials and product in the whole technology, finally obtains electron level N-methylformamide to still retrieve the raw materials through increasing equipment in whole technology, can reduce raw and other materials and power consumption, also can reduce operating cost.

In order to achieve the above purpose, the utility model discloses technical scheme as follows:

the utility model provides a preparation system of electronic grade N-methylformamide, including methyl formate reactor and amination reactor of interconnect, amination reactor is connected with product refining unit and is used for obtaining electronic grade N-methylformamide with the refined purification of N-methylformamide who obtains;

the methyl formate reactor is communicated with a carbon monoxide purification unit through a pipeline, CO purified by the carbon monoxide purification unit enters the methyl formate reactor to carry out esterification reaction, and the carbon monoxide purification unit comprises two parallel adsorption towers.

Preferably, as a further implementable scheme, the methyl formate reactor is communicated with a methanol rectifying tower through a pipeline, and refined methanol refined by the methanol rectifying tower enters the methyl formate reactor to perform esterification reaction with CO.

Preferably, as a further implementable scheme, a reaction expansion tank, a salt filter and a methyl ester rectifying tower are sequentially connected between the methyl formate reactor and the amination reactor, and a reaction liquid entering the reaction expansion tank passes through the salt filter to remove a waste catalyst, enters the methyl ester rectifying tower to be separated and purified, and then goes to the amination reactor.

Preferably, as a further practicable scheme, the methyl ester rectifying tower is connected with a first methanol recovery tower, and methanol coming out of the bottom of the methyl ester rectifying tower goes to the methanol recovery tower for recycling.

Preferably, as a further implementable scheme, the product refining unit comprises an aging tank, a light component removal tower, a refining tower and an ion adsorber which are connected in sequence, wherein a reaction liquid overflowing from an overflow port on the amination reactor enters the aging tank, then enters the light component removal tower from the aging tank to remove methanol, and finally is refined by the refining tower to be treated by the ion adsorber.

Preferably, as a further implementable scheme, the ion adsorber comprises two ion adsorbers connected in parallel, and the top of each ion adsorber is provided with a product extraction port of electronic-grade N-methylformamide.

Preferably, as a further implementable scheme, a second methanol recovery tower and a dealcoholization tower are sequentially connected between the light component removal tower and the refining tower, the bottom of the light component removal tower is communicated with the second methanol recovery tower, and the bottom of the second methanol recovery tower is connected with the side wall of the dealcoholization tower through a pipeline so as to further dealcoholize the crude product liquid at the bottom of the second methanol recovery tower.

Preferably, as a further practicable scheme, the system further comprises a post-treatment tower, wherein the post-treatment tower is communicated with the tower bottom of the refining tower through a pipeline and is used for further recovering and treating the heavy components at the tower bottom of the refining tower.

Preferably, as a further implementable scheme, the post-treatment tower and the dealcoholization tower are both connected with the aging tank through pipelines and are used for recycling light components extracted from the top of the tower.

Preferably, as a further implementable scheme, the top of the methyl formate reactor is sequentially provided with a first reaction tail gas condenser and a second reaction tail gas condenser, methanol and methyl formate carried at the top of the methyl formate reactor are recovered, and then tail gas is directly discharged.

The utility model discloses an electron level N-methylformamide preparation system, whole process flow have realized continuous operation, have all realized refining to raw materials carbon monoxide, methyl alcohol to can guarantee that N-methylformamide reaches the electron rank, still in addition through increasing purification filtration equipment, improve the quality of product, extra recovery plant carries out effectual recovery to the material of output in the whole flow in addition, reduces the energy consumption and practices thrift the cost, fully reaches the purpose that reduces raw and other materials consumption.

Drawings

Various additional advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

fig. 1 is a process flow diagram of a preparation system of the intermediate-electron-grade N-methylformamide of the present invention.

In the figure: 1-a methanol feed tank; 2-methanol metering pump; 3-methanol rectification column; 4-refined methanol tank; a 5-methyl formate reactor; 6-a fine methanol metering pump; 7-a catalyst tank; 8-a first adsorption column; 9-a second adsorption column; 10-reaction liquid circulating pump; 11-a reaction liquid cooler; 12-a first reaction tail gas condenser; 13-a second reaction tail gas condenser; 14-a reactive expansion tank; 15-salt filter; a 16-methyl ester rectification column; 17-a first methanol recovery column; an 18-methyl ester feed pump; 19-reaction circulation pump; 20-amination reactor; 21-a reaction cooler; 22-aging tank; 23-a light component removal tower feed pump; 24-a light component removal tower; 25-a second methanol recovery column; 26-dealcoholizing tower; 27-a refining column; 28-a post-treatment column; 29-kettle liquid pump; 30-a product pump; 31-a first ion adsorber; 32-a second ion adsorber; 33-overhead extraction pump; 34-a bottom extraction pump.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings and detailed description, but those skilled in the art will understand that the following described embodiments are some, not all, of the embodiments of the present invention, and are only used for illustrating the present invention, and should not be construed as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention. The examples, in which specific conditions are not specified, were carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In order to explain the technical solution of the present invention more clearly, the following description is made in the form of specific embodiments.

Examples

Referring to fig. 1, the present invention provides a system for preparing electronic grade N-methylformamide, which mainly comprises a methyl formate reactor 5 and an amination reactor 20. After esterification reaction of methanol and CO in a methyl formate reactor 5, the product of the esterification reaction enters an amination reactor 20 to react with monomethylamine for amination, and N-methylformamide is generated.

In order to improve the grade of products, raw material industrial methanol and CO need to be refined in advance, the industrial methanol is firstly sent into a methanol raw material tank 1 through a pipeline, is pumped into a methanol rectifying tower 3 communicated with a methyl formate reactor 5 through a methanol metering pump 2, rectified methanol is extracted from the methanol rectifying tower 3, and is sent into a rectified methanol tank 4 through a pipeline. The refined methanol is fed into the middle part of the methyl formate reactor 5 through a refined methanol metering pump 6. Catalyst sodium methoxide is sent into a catalyst tank 7 through a pipeline, and is sent into the top and the bottom of a methyl formate reactor 5 to participate in reaction after being pressurized by a catalyst pump.

Carbon monoxide from the outside of the boundary area is sent into a carbon monoxide purification unit through a pipeline for adsorption purification, the carbon monoxide purification unit comprises two adsorption towers connected in parallel, a first adsorption tower 8 and a second adsorption tower 9, the carbon monoxide is sent into the first adsorption tower 8 through the pipeline for purification, and the carbon monoxide discharged from the first adsorption tower 8 is sent into a gas distributor in the methyl formate reactor 5 through the pipeline for dispersion and then reacts with refined methanol. The second adsorption tower 9 is connected with the first adsorption tower 8 in parallel through a pipeline, when the first adsorption tower 8 is in a working state, the second adsorption tower 9 is in a regeneration state, and vice versa, the working state that two adsorption towers are opened and prepared can be formed, operation switching is convenient, and the purity after carbon monoxide purification is ensured.

The reaction liquid in the methyl formate reactor 5 is pumped out by a reaction liquid circulating pump 10, and a part of the reaction liquid is returned to the methyl formate reactor 5 for continuous reaction after reaction heat is removed by a reaction liquid cooler 11. Inert components in CO gas are gathered at the top of the reactor, the inert components are discharged out of the methyl formate reactor 5 through a pressure regulating valve, a first reaction tail gas condenser 12 and a second reaction tail gas condenser 13 are sequentially arranged at the top of the methyl formate reactor 5, tower top tail gas is cooled and condensed through refrigerant liquid to recover methanol and methyl formate carried in the inert components, and then reaction tail gas is discharged to the outside.

The device comprises a reaction expansion tank 14, a salt filter 15 and a methyl ester rectifying tower 16 which are sequentially connected between a methyl formate reactor 5 and an amination reactor 20, wherein the other part of reaction liquid from a reaction liquid circulating pump 10 enters the reaction expansion tank 14 for pressure reduction, a flash evaporated gas phase enters the methyl ester rectifying tower 16, and a liquid phase in the reaction expansion tank 14 enters the methyl ester rectifying tower 16 for separation after solid waste catalysts are removed by the salt filter 15.

Methyl formate vapor sent out from the top of the methyl ester rectifying tower 16 is condensed by a methyl ester tower condenser to be used as reflux, and a part of the methyl formate vapor is sent back to the top of the methyl ester rectifying tower 16 as reflux liquid to enter the tower; another portion is fed to amination reactor 20. The methyl ester rectifying tower 16 is connected with a first methanol recovery tower 17, methanol discharged from the tower bottom of the methyl ester rectifying tower 16 enters the first methanol recovery tower 17, and recovered methanol extracted from the tower top of the first methanol recovery tower 17 returns to the methanol raw material tank 1 for recycling.

Methyl formate condensed at the top of the methyl formate rectifying tower 16 enters an amination reactor 20 after being pressurized by a methyl formate feed pump 18, and amination reaction liquid is pressurized by a reaction circulating pump 19, cooled by a reaction cooler 21 and then enters the amination reactor 20 from the top; monomethylamine enters from the lower part of the amination reactor 20, and the monomethylamine and methyl formate carry out amination reaction in the amination reactor 20 to generate N-methylformamide and methanol.

The amination reactor 20 is connected with a product refining unit for purifying and refining the obtained N-methylformamide to obtain electronic-grade N-methylformamide, the product refining unit comprises an aging tank 22, a light component removal tower 24, a refining tower 27 and an ion adsorber which are connected in sequence, and reaction liquid overflows from an overflow port on the upper side of the amination reactor 20 and flows into the aging tank 22. After sufficient retention, the reaction liquid entering the aging tank 22 is pumped out by a light component removal tower feeding pump 23, enters the middle part of a light component removal tower 24, and a part of the top of the light component removal tower 24 is extracted and sent back to the amination reactor 20 for continuous reaction.

A second methanol recovery tower 25 and a dealcoholization 26 which are connected in sequence are arranged between the light component removal tower 24 and the refining tower 27, the kettle liquid of the light component removal tower 24 enters the middle part of the second methanol recovery tower 25, and the methanol extracted from the top of the second methanol recovery tower 25 is returned to the methanol material tank 1. Sending the crude product liquid at the bottom of the second methanol recovery tower 25 into the middle part of the dealcoholization tower 26, and sending the produced liquid at the top of the dealcoholization tower 26 to the aging tank 22 for continuous reaction; the bottom liquid of the dealcoholization tower 26 enters the middle part of a refining tower 27, qualified N-methylformamide products extracted from the top of the refining tower 27 enter an ion absorber through pressurization of a product pump 30, the ion absorber comprises two ion absorbers connected in parallel, a first ion absorber 31 and a second ion absorber 32, and after anion cations are absorbed, electronic-grade N-methylformamide is obtained, and the top of each ion absorber is provided with a product extraction port of the electronic-grade N-methylformamide.

And a post-treatment tower 28 is also connected with the refining tower 27 in sequence, the residue of the refining tower 27 is conveyed to the post-treatment tower 28 by a kettle liquid pump 29, and the top of the post-treatment tower 28 is conveyed to the ageing tank 22 by a top extraction pump 33. In short, both the post-treatment tower 28 and the dealcoholization tower 26 are connected with the aging tank 22 through pipelines and are used for respectively recycling light components extracted from the corresponding tower tops, and the tower bottom material of the post-treatment tower 28 is sent to the outside for treatment by a tower bottom extraction pump 34.

The utility model provides a preparation system mainly includes processes such as raw materials purification, product purification and process material recovery.

The raw materials for production such as carbon monoxide, methanol and the like before entering the methyl formate reactor are purified, so that the precision of the raw materials is improved, and the production quality of products is ensured.

After the raw materials react, the product is purified and refined by different devices in the refining unit, so that the precision of the N-methylformamide is effectively improved, and the electronic-grade N-methylformamide can be reliably and stably obtained.

In the production process, methanol of light components at the top of the tower in different towers is recycled, so that the consumption of raw materials is effectively reduced, compared with a methanol condensation and re-conveying mode, the consumption of public and auxiliary power is reduced to the greatest extent, and the production cost is greatly reduced.

Finally, it is to be understood that the above embodiments are merely exemplary embodiments that have been employed to illustrate the principles of the present invention, and that the present invention is not limited thereto. It will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention, and these changes and modifications are to be considered as the protection scope of the invention.

Claims

1. The preparation system of the electronic-grade N-methylformamide is characterized by comprising a methyl formate reactor and an amination reactor which are connected with each other, wherein the amination reactor is connected with a product refining unit and is used for purifying and refining the obtained N-methylformamide to obtain the electronic-grade N-methylformamide;

the methyl formate reactor is communicated with a carbon monoxide purification unit through a pipeline, CO purified by the carbon monoxide purification unit enters the methyl formate reactor to perform esterification reaction, and the carbon monoxide purification unit comprises two adsorption towers connected in parallel.

2. The preparation system of claim 1, wherein the methyl formate reactor is communicated with a methanol rectifying tower through a pipeline, and refined methanol refined by the methanol rectifying tower enters the methyl formate reactor to perform esterification reaction with CO.

3. The preparation system of claim 2, wherein a reaction expansion tank, a salt filter and a methyl ester rectifying tower are sequentially connected between the methyl formate reactor and the amination reactor, and reaction liquid entering the reaction expansion tank is subjected to the salt filter to remove waste catalyst, enters the methyl ester rectifying tower to be separated and purified, and then goes to the amination reactor.

4. The preparation system of claim 3, wherein the methyl ester rectifying tower is connected with a first methanol recovery tower, and the methanol coming out of the bottom of the methyl ester rectifying tower goes to the methanol recovery tower for recycling.

5. The preparation system of any one of claims 1 to 4, wherein the product refining unit comprises an aging tank, a light component removal tower, a refining tower and an ion adsorber which are connected in sequence, reaction liquid overflowing from an overflow port on the amination reactor enters the aging tank, then enters the light component removal tower from the aging tank to remove methanol, and finally is refined by the refining tower to be treated by the ion adsorber.

6. The production system of claim 5, wherein the ion adsorber comprises two ion adsorbers connected in parallel, each ion adsorber having a product withdrawal port for electronic grade N-methylformamide disposed at a top thereof.

7. The preparation system of claim 5, wherein the light component removal tower and the refining tower comprise a second methanol recovery tower and a dealcoholization tower which are connected in sequence, the bottom of the light component removal tower is communicated with the second methanol recovery tower, and the bottom of the second methanol recovery tower is connected with the side wall of the dealcoholization tower through a pipeline, so that the bottom crude product liquid of the second methanol recovery tower is subjected to further dealcoholization.

8. The system of claim 7, further comprising a post-treatment column in communication with the bottom of the refining column via a conduit for further recycling of the heavies from the bottom of the refining column.

9. The preparation system of claim 8, wherein the post-treatment tower and the dealcoholization tower are connected with the aging tank through pipelines for recycling light components extracted from the top of the tower.

10. The preparation system of any one of claims 1 to 4, wherein a first reaction tail gas condenser and a second reaction tail gas condenser are sequentially arranged at the top of the methyl formate reactor, and methanol and methyl formate carried in the top of the methyl formate reactor are recovered, and then tail gas is directly discharged.