阅读说明：本技术 一种重氮甲烷的工业化生产系统 (Industrial production system of diazomethane ) 是由 李鹏飞 杨茜 黄长如 刁焕武 张秋达 于 2020-04-30 设计创作，主要内容包括：本发明提供了一种重氮甲烷的工业化生产系统,采用具有R-N(NO)-CH<Sub>3</Sub>结构基团的物质在碱性条件下进行催化降解制备重氮甲烷工艺,包括进料系统、反应与换热系统和分离系统,所述进料系统和反应与换热系统之间通过化工管道连接,原料在反应与换热系统中经过催化降解反应生成含有重氮甲烷的溶液,所述反应与换热系统通过化工管道与分离系统连接,在反应与换热系统中生成的含有重氮甲烷的溶液流到分离系统中进行分离提纯,得到重氮甲烷。本发明利用微通道反应器技术实现重氮甲烷的过程可控的工业化生产,有效的解决了目前工艺及生产过程中的反应环节存在的安全性问题,从而实现了重氮甲烷的工业化生产。(The invention provides an industrial production system of diazomethane, which adopts a process of preparing diazomethane with R-N (NO) -CH 3 The process for preparing the diazomethane by carrying out catalytic degradation on substances with structural groups under an alkaline condition comprises a feeding system, a reaction and heat exchange system and a separation system, wherein the feeding system is connected with the reaction and heat exchange system through a chemical pipeline, raw materials are subjected to catalytic degradation reaction in the reaction and heat exchange system to generate a solution containing the diazomethane, the reaction and heat exchange system is connected with the separation system through the chemical pipeline, and the solution containing the diazomethane generated in the reaction and heat exchange system flows into the separation system to be separated and purified, so that the diazomethane is obtained. The invention utilizes the microchannel reactor technology to realize the process-controllable industrial production of the diazomethane, effectively solves the safety problem existing in the reaction link in the prior process and the production process, and further realizes the industrial production of the diazomethane.)

1. An industrial production system of diazomethane adopts a process of preparing diazomethane with R-N (NO) -CH₃The process for preparing the diazomethane by catalytic degradation of substances with structural groups under the alkaline condition is characterized by comprising the following steps of: comprises a feeding system, a reaction and heat exchange system and a separation system, wherein a chemical pipeline (4) is arranged between the feeding system and the reaction and heat exchange systemThe reaction and heat exchange system is connected with the separation system through a chemical pipeline (4);

the reaction and heat exchange system comprises a microchannel reactor (21), wherein the microchannel reactor (21) is formed by connecting a plurality of microchannel reactor units in series, two feed inlets, one discharge outlet, one heat exchange medium inlet and one heat exchange medium outlet are arranged on the microchannel reactor (21), and the heat exchange medium inlet and the heat exchange medium outlet of the microchannel reactor (21) are respectively connected with a heat exchange pipeline (22);

the feed system, which is a liquid feed, comprises R-N (NO) -CH₃A structural substance solution tank (11), an alkaline solution tank (12), a diaphragm pump (13) and a flow meter (14), wherein R-N (NO) -CH₃The structural substance solution tank (11) is connected with one feed inlet of the microchannel reactor (21) through a chemical pipeline (4), a diaphragm pump (13) and a flowmeter (14) are sequentially arranged on the chemical pipeline (4), the alkali solution tank (12) is connected with the other feed inlet of the microchannel reactor (21) through the chemical pipeline (4), and the diaphragm pump (13) and the flowmeter (14) are sequentially arranged on the chemical pipeline (4);

the separation system comprises a phase separation tank (31) and a water absorption tower (33), wherein the phase separation tank (31) is used for separating diazomethane organic solvent and other solutions, a feed inlet, a heavy component outlet and a light component outlet are formed in the phase separation tank (31), a feed inlet and a discharge outlet are formed in the water absorption tower (33), the phase separation tanks (31) are arranged in parallel, the light component outlet of the phase separation tank (31) is communicated to a waste alkali liquor storage tank through a chemical pipeline (4), the heavy component outlet of each phase separation tank (31) is connected with two water absorption towers (33) after being branched through the chemical pipeline (4), the water absorption towers (33) are arranged in parallel, the chemical pipeline (4) connected with the feed inlet of the water absorption tower (33) is connected with a high-temperature steam pipeline (32), and the chemical pipeline (4) connected with the discharge outlet of the water absorption towers (33) is also branched, one path leads to the next step of the diazomethane, the other path leads to a waste liquid tank, valves are arranged on chemical pipelines (4) connecting the phase separation tank (31) and the water absorption tower (33), the phase separation tanks (31) which are connected in parallel are mutually standby, and the water absorption tower (33) behind the phase separation tank (31) which normally works is enabled to work alternately.

2. The industrial production system of diazomethane as set forth in claim 1, characterized in that: the liquid holdup of the microchannel reactor unit was 200-300 ml.

3. The industrial production system of diazomethane as set forth in claim 1, characterized in that: and the microchannel reactor unit is provided with a thermal resistor.

4. The industrial production system of diazomethane as set forth in claim 1, characterized in that: and a heat exchange pipeline (22) connected with a heat exchange medium inlet of the microchannel reactor (21) is provided with a pump and a valve.

5. The industrial production system of diazomethane as set forth in claim 3, characterized in that: the thermal resistor is controlled by the linkage of a pump and a valve on the heat exchange pipeline (22).

6. The industrial production system of diazomethane as set forth in claim 1, characterized in that: at least one microchannel reactor (21) is provided.

7. The industrial production system of diazomethane as set forth in claim 1, characterized in that: the diaphragm pump (13) is a three-pump head diaphragm metering pump, and a pressure transmitter and a safety valve are arranged at the outlet of the diaphragm pump (13).

8. The industrial production system of diazomethane as set forth in claim 1, characterized in that: and the water absorption tower (33) is filled with water absorption resin filler.

Technical Field

The invention relates to the technical field of organic compound preparation, in particular to an industrial production system of diazomethane.

Background

Diazomethane is an important organic intermediate and synthesis factor in fine organic synthesis, is mainly used for the production of medicines and pesticides, such as the production of L-phenylalanine chloromethyl ketone, and the like, is yellow toxic gas with strong irritation and moldy smell at normal temperature and normal pressure, is extremely flammable, has heavier gas than air, can flow along the ground, can cause remote ignition, can explode when being heated, contacted with open fire or being rubbed, vibrated and impacted, and can cause explosion when being contacted with alkali metal or rough surfaces of objects without dilution liquid or gas.

Diazomethane is difficult to be prepared by directly reacting methylamine with nitrous acid, and the preparation method of diazomethane mainly comprises two methods: R-N (NO) -CH₃Basic degradation of structure and chloroform hydrazine hydrate method, the most common method is to use the catalyst having R-N (NO) -CH₃The diazomethane is prepared by the catalytic degradation of substances with structural groups under the alkaline condition, wherein R is sulfonyl and carbonyl electron-withdrawing groups (the compounds with the structure comprise 1-methyl-3-nitro-1-nitrosoguanidine (MNNG), N-methyl-N-nitrosamine (MNA), N-methyl-N-nitroso-p-toluidine (Diazald), N-methyl-N-nitrosourea (MNU) and di- (N-methyl-N-nitroso) p-benzamide), and the reaction equation is as follows:

R-N(NO)-CH₃+OH^-→CH₂N₂+H₂O+R-O^-

in the chemical reaction, the catalyst is prepared from a catalyst containing R-N (NO) -CH₃The organic solvent solution of the structural group substance is reacted with an aqueous solution of an inorganic base to prepare the diazomethane, the destination of the prepared product is determined by the nature of the solvent, so that the diazomethane is obtained by oil-water separation and purification from the product, and the diazomethane separated from the reaction system must be immediately used to avoid the danger of leakage and explosion.

Because diazomethane is a strong carcinogenic, highly toxic, flammable and explosive gas, the permissible exposure limit of diazomethane is 0.2ppm within 8 hours of working day according to relevant regulations; the preparation process belongs to a strong exothermic reaction, the danger is very high, and most of the explosion accidents of the diazomethane occur in the distillation process by integrating the accidents occurring in the diazomethane preparation process, so that the current process for preparing the diazomethane in a laboratory is difficult to be applied to batch preparation of industrial production after being amplified by the traditional process line due to the reasons.

Disclosure of Invention

The invention provides an industrial production system of diazomethane, which utilizes a microchannel reactor technology to realize the industrial production of diazomethane with controllable process, effectively solves the safety problem existing in the reaction link in the prior process and the production process, and a plurality of groups of systems contain two different separation devices, and the separation devices with different numbers are started according to the actual production requirement, thereby not only eliminating the potential safety hazard in the distillation process, but also realizing the production according to the requirement, and further ensuring the safety of the industrial production.

The invention adopts the following technical scheme:

an industrial production system of diazomethane adopts a process of preparing diazomethane with R-N (NO) -CH₃The process for preparing the diazomethane by carrying out catalytic degradation on substances with structural groups under an alkaline condition comprises a feeding system, a reaction and heat exchange system and a separation system, wherein the feeding system and the reaction and heat exchange system are connected through a chemical pipeline, raw materials are conveyed from the feeding system to the reaction and heat exchange system according to process requirements, the raw materials are subjected to catalytic degradation reaction in the reaction and heat exchange system to generate a solution containing the diazomethane, the reaction and heat exchange system is connected with the separation system through the chemical pipeline, and the solution containing the diazomethane generated in the reaction and heat exchange system flows into the separation system for separation and purification to obtain the diazomethane;

the reaction and heat exchange system comprises a microchannel reactor, wherein the microchannel reactor is formed by connecting a plurality of microchannel reactor units in series, the interior of each microchannel reactor unit is formed by connecting a plurality of microtubes with the diameters of 10-500 mu m in parallel, the specific surface area is very large, chemical reaction occurs in the channels, because the volumes of the microtubes in the microchannel reactor units are limited, a plurality of microchannel reactors are connected in series for use according to different fluxes, in order to enable substances in the microchannel reactors to react at proper temperature, the microchannel reactor units are also provided with heat exchange channels, the heat exchange channels on the microchannel reactor units are connected in parallel, the reaction temperature of each microchannel reactor unit is ensured to be consistent, two feed inlets, one discharge outlet, one heat exchange medium inlet and one heat exchange medium outlet are arranged on the microchannel reactor, a heat exchange medium inlet and a heat exchange medium outlet of the microchannel reactor are respectively connected with a heat exchange pipeline;

the feed system, which is a liquid feed, comprises R-N (NO) -CH₃A structural material solution tank, an alkaline solution tank, a diaphragm pump and a flow meter, wherein R-N (NO) -CH₃The structural material solution tank is connected with one feed inlet of the microchannel reactor through a chemical pipeline, a diaphragm pump and a flowmeter are sequentially arranged on the chemical pipeline, the alkali solution tank is connected with the other feed inlet of the microchannel reactor through the chemical pipeline, and the diaphragm pump and the flowmeter are sequentially arranged on the chemical pipeline in the same way, so that raw materials can enter the microchannel reactor to react according to a reasonable proportion;

the separation system comprises a phase separation tank and water absorption towers, wherein the phase separation tank is used for separating diazomethane organic solvent and other solutions, the phase separation tank is provided with a feed inlet, a heavy component outlet and a light component outlet, the water absorption tower is used for absorbing a small amount of moisture in the diazomethane organic solution, the water absorption tower is provided with a feed inlet and a discharge outlet, the feed inlet of the phase separation tank is connected with the discharge outlet on the microchannel reactor through a chemical pipeline, the phase separation tanks are arranged in parallel, the light component outlet of the phase separation tank is communicated to a waste alkali liquor storage tank through a chemical pipeline, the heavy component outlet of each phase separation tank is connected with two water absorption towers after being branched through the chemical pipeline, the water absorption towers are arranged in parallel, the chemical pipeline connected with the feed inlet of the water absorption tower is connected with a high-temperature steam pipeline, and the chemical pipeline connected with the discharge outlet of the water absorption towers is also branched, one path leads to the next step of the diazomethane, the other path leads to the waste liquid tank, valves are arranged on chemical pipelines connecting the phase separation tank and the water absorption tower, the phase separation tanks which are connected in parallel are mutually standby, and the water absorption tower behind the phase separation tank which works normally works is enabled to work alternately.

Further, the liquid holdup of the microchannel reactor unit is 200-300 ml.

Furthermore, a thermal resistor is arranged on the microchannel reactor unit and used for detecting the temperature in the reaction channel in real time.

Furthermore, a pump and a valve are arranged on a heat exchange pipeline connected with a heat exchange medium inlet of the microchannel reactor.

Furthermore, the thermal resistor is in linkage control with a pump and a valve on the heat exchange pipeline, so that accurate temperature control is guaranteed, optimal adjustment of reaction is realized, and energy consumption is reduced.

Furthermore, at least one microchannel reactor is arranged, and when the flux of the microchannel reactor is too large and the pressure drop is too large and exceeds the design pressure of the microchannel reactor, the number of the microchannel reactors needs to be increased, and the newly increased microchannel reactor is connected with the original microchannel reactor in parallel.

Further, the separation system is correspondingly added after the newly added microchannel reactor.

Furthermore, the diaphragm pump is a three-pump head diaphragm metering pump, and a pressure transmitter and a safety valve are arranged at the outlet of the diaphragm pump.

Further, the flowmeter is a mass flowmeter.

Further, the water absorption tower is filled with water absorption resin filler.

The industrial production system of diazomethane of the invention, regard microchannel reactor as the core equipment of reaction and heat exchange system, because of the regularity of microchannel in the microchannel reactor makes analysis and simulation to the microreactor easier and simpler than the traditional reactor, in the industrial production, only need to increase the quantity of the microreactor unit, namely the numerical value is amplified, will not produce the amplification effect of other reactors, thus has greatly saved the experimental cost, has shortened the development cycle.

The industrial production system of the diazomethane takes the microchannel reactor as the core equipment of the reaction and heat exchange system, and due to the characteristics of the microchannel reactor, the volume of reactants in the microchannel is small, the heat and mass transfer rate is very high, a large amount of heat generated by the strong exothermic chemical reaction can be removed in time, and for the chemical reaction which is easy to explode, the size of the microchannel is usually in the micron-sized range, so that the chain reaction can be effectively blocked, the reaction can be stably carried out in the explosion limit range, and the safety problem in production is effectively solved.

According to the industrial production system of the diazomethane, the phase separation tanks connected in parallel in the separation system are mutually standby, the water absorption tower behind the normally working phase separation tank works alternately, and the maximum amount of the diazomethane in the phase separation tank and the water absorption tower does not exceed a certain value, so that the safety is greatly improved.

The invention has the beneficial effects that:

1. according to the industrial production system of the diazomethane, disclosed by the invention, the advantages of high mass transfer and heat transfer rates, capability of improving the selectivity and yield and the like of the microchannel reactor are utilized, and the continuous production of the diazomethane from reaction to separation and purification is realized by matching with the phase-splitting tank and the absorption tower, no moving part is required in the whole process, the whole process is automatically monitored and operated, no operator is required, the repeatability and stability of the product quality are improved, and the labor intensity is reduced.

2. The industrial production system of the diazomethane has the advantages of safe production, small reaction volume and reduction of accidents caused by equipment failure and misoperation.

3. The industrial production system of diazomethane has the advantages of whole process closed operation, safety, no leakage point, no pollution and no danger caused by the leakage of diazomethane.

4. The industrial production system of diazomethane has adjustable and controllable operation conditions and has the advantages of controllable reaction concentration, temperature and residence time.

5. The industrial production system of the diazomethane has the advantages of enhancing mixing and heat transfer, improving the reaction rate and reducing byproducts.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic view of an industrial production system according to the present invention

In the figure: 4-chemical pipeline, 11-R-N (NO) -CH₃The system comprises a structural material solution tank, a 12-alkaline solution tank, a 13-diaphragm pump, a 14-flowmeter, a 21-microchannel reactor, a 22-heat exchange pipeline, a 31-phase separation tank, a 32-steam pipeline and a 33-water absorption tower.

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.

In addition, the descriptions related to "first", "second", etc. in the present invention are only for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.