Continuous flow reaction system for synthesizing 3-hexyne-2, 5-diol

Abstract

The utility model relates to a continuous flow reaction system for synthesizing 3-hexyne-2, 5-diol, which comprises an acetaldehyde generator, a non-return container, a gas supercharger and a micro-channel reactor which are communicated in sequence, the micro-channel reactor comprises a mixing area and a reaction area which are communicated in sequence, the mixing area and the reaction area respectively comprise a plurality of micro-channel reaction modules which are communicated in sequence, and the micro-channel reaction modules are communicated with the non-return container. And a gas outlet of the gas supercharger is connected to a channel inlet of the reaction area. The continuous flow reaction device disclosed by the utility model has the beneficial effects that the continuous flow reaction for synthesizing 3-hexyne-2, 5-diol can be realized, the reaction conditions are accurately controlled, and the continuous flow reaction device has the advantages of safety, high efficiency, low energy consumption, low cost and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical production, and particularly relates to a continuous flow reaction system for synthesizing 3-hexyne-2,5-diol. Background Art

[0002] 3-Hexyne-2,5-diol (HD) is a chemical intermediate with good wettability, low foam defoaming property, high dispersibility, excellent corrosion inhibition property and other properties, and has a very wide range of uses. At present, this product is an important raw material for a new type of electroplating brightener, and also an important chemical raw material for new medicines. At the same time, it can be used as a key effective component of a high-efficiency acidification corrosion inhibitor under high temperature, high pressure and high concentration hydrochloric acid in oil and gas wells, and the product has a broad application prospect.

[0003] The traditional production process of 3-hexyne-2,5-diol (HD) mainly has the following disadvantages: 1. The reaction device mainly uses traditional high-pressure / atmospheric pressure reaction kettles, and the production adopts batch reaction. There are many reaction steps and the reaction conditions are complex to control, and the continuous process cannot be realized; 2. Using the traditional high-pressure reaction process, the reaction temperature is controlled high. In the actual production process, the pressure of the high-pressure kettle needs to be strictly controlled, and the production process is highly dangerous; 3. It is necessary to use the raw material acetylene gas. As a flammable gas, acetylene is prone to explosion and other dangers due to operation errors or management negligence during traditional production and use; 4. The entire reaction time is relatively long, usually several hours. In the later stage of the reaction, a large amount of reaction by-products increase, resulting in a sticky substance in the reactants, which prevents the reaction from continuing. Summary of the Utility Model

[0004] The purpose of the utility model is to overcome the shortcomings of the prior art and provide a continuous flow reaction system for synthesizing 3-hexyne-2,5-diol, so as to realize the continuous, safe, efficient and stable production of 3-hexyne-2,5-diol.

[0005] The purpose of the utility model is realized by the following technical solutions:

[0006] A continuous flow reaction system for synthesizing 3-hexyne-2,5-diol includes an acetaldehyde generator, a check valve container, a gas booster and a microchannel reactor connected in sequence. The microchannel reactor includes a mixing zone and a reaction zone connected in sequence. Both the mixing zone and the reaction zone include a plurality of microchannel reaction modules connected in sequence. The gas outlet of the gas booster is connected to the channel inlet of the reaction zone.

[0007] Furthermore, the acetaldehyde generator includes a round-bottom flask and a dropping funnel. The top side wall of the round-bottom flask is provided with a liquid inlet, and the dropping funnel is connected to the round-bottom flask through the liquid inlet. The check valve container is connected to the top bottle mouth of the round-bottom flask.

[0008] Further, the check valve container includes a conical flask. The top opening of the conical flask is communicated with the top opening of a round-bottom flask through a condenser tube, and the air inlet of the gas booster is communicated with the top side wall of the conical flask.

[0009] Further, a stainless steel pump is connected to the channel inlet of the mixing zone.

[0010] Further, a pressure controller is connected to the channel outlet of the reaction zone.

[0011] Compared with the prior art, the utility model has the following beneficial effects:

[0012] 1. Through the arrangement of the acetaldehyde reactor, the check valve container, the gas booster and the microchannel reactor, the utility model can realize the continuous flow reaction for synthesizing 3-hexyne-2,5-diol, strengthen the reaction process, reduce the contact time of reactants, shorten the reaction production cycle, reduce the generation of reaction by-products, ensure the continuity of the reaction, and reduce the production cost.

[0013] 2. The continuous flow reaction system of the utility model can improve the reaction mixing uniformity, accurately control the residence time of materials in each area, avoid the decomposition of reactants or products due to instability, improve the reaction rate, expand the process condition selection range, realize the effective control of the process conditions of the synthesis route, and increase the safety factor.

[0014] 3. Compared with the traditional batch process for synthesizing 3-hexyne-2,5-diol, the continuous flow reaction system of the utility model has the advantages of less liquid holdup in the reaction zone, accurate temperature control, process intensification, no scale-up effect, etc.

[0015] 4. Compared with the traditional batch process, the continuous flow reaction system of the utility model uses continuous flow reaction to synthesize 3-hexyne-2,5-diol, which can essentially eliminate potential production safety hazards, the reaction production process is green and environmentally friendly, and seamless scale-up from small-scale test to industrialization can be realized.

[0016] 5. The continuous flow reaction system of the utility model is a fluid device without moving parts, and the mixing reaction is only realized by the conveying power of the pump, so the production energy consumption can be reduced. Description of the Drawings

[0017] Figure 1 is a schematic diagram of the overall structure of the utility model;

[0018] Figure 2 is a schematic diagram of the process flow for synthesizing 3-hexyne-2,5-diol of the utility model.

[0019] In the figure: 1. Acetaldehyde generator; 11. Round-bottom flask; 12. Dropping funnel; 2. Check valve container; 3. Gas booster; 4. Microchannel reactor; 41. Mixing zone; 42. Reaction zone; 5. Microchannel reaction module; 6. Condenser; 7. Pressure controller. Detailed implementation mode

[0020] The following further describes the present utility model in conjunction with the attached drawings, but the protection scope of the present utility model is not limited to the following.

[0021] As shown in Figure 1, a continuous flow reaction system for synthesizing 3-hexyne-2,5-diol includes an acetaldehyde generator 1, a check valve container 2, a gas booster 3, and a microchannel reactor 4 that are connected in sequence. The acetaldehyde generator 1 is used to react and prepare acetaldehyde gas, and the acetaldehyde gas is then introduced into the gas booster 3 for pressurization; the check valve container 2 is used to prevent backflow when the acetaldehyde gas passes from the acetaldehyde generator 1 to the gas booster 3; the pressurized acetaldehyde gas is then introduced into the microchannel reactor 4 for reacting to prepare 3-hexyne-2,5-diol.

[0022] The acetaldehyde generator 1 includes a round-bottom flask 11 and a dropping funnel 12. The top side wall of the round-bottom flask 11 is provided with a liquid inlet, and the dropping funnel 12 is connected to the round-bottom flask 11 through the liquid inlet. When preparing acetaldehyde gas, paraldehyde solution is added to the round-bottom flask 11, and concentrated sulfuric acid solution is dropped into the round-bottom flask 11 through the dropping funnel 12. The paraldehyde solution and the concentrated sulfuric acid solution are mixed and reacted to obtain acetaldehyde gas. A thermometer is connected to the top bottle mouth of the round-bottom flask to observe the distillation temperature during the reaction and judge whether the distilled substance is acetaldehyde according to the distillation temperature. Specifically, when the distillation temperature is 39 °C, it can be judged that the distilled substance is acetaldehyde, and if the temperature rises, the distilled substance is not acetaldehyde.

[0023] The check valve container 2 includes a conical flask. The top bottle mouth of the conical flask is connected to the top bottle mouth of the round-bottom flask 11 through a condenser 6, and the air inlet of the gas booster 3 is connected to the top side wall of the conical flask. The prepared acetaldehyde gas enters the check valve container 2 after being cooled by the condenser 6 and then is introduced into the gas booster 3.

[0024] The microchannel reactor 4 includes a mixing zone 41 and a reaction zone 42 that are connected in sequence. Both the mixing zone 41 and the reaction zone 42 include a plurality of microchannel reaction modules 5 that are connected in sequence. The outlet of the gas booster 3 is connected to the channel inlet of the reaction zone 42. When preparing 3-hexyne-2,5-diol, first add the mixed solution of xylene and catalyst to the mixing zone 41, and at the same time introduce acetylene gas into the mixing zone 41. The xylene, catalyst, and acetylene gas are fully mixed after passing through the plurality of microchannel reaction modules 5 in the mixing zone 41 in sequence to obtain a mixed solution mixed with acetylene gas. Then, the mixed solution mixed with acetylene gas will enter the reaction zone 42. When the mixed solution mixed with acetylene gas enters the reaction, at the same time introduce the pressurized acetaldehyde gas into the reaction zone 42. The mixed solution mixed with acetylene gas and the acetaldehyde gas are fully reacted after passing through the plurality of microchannel reaction modules 5 in the reaction zone 42 in sequence to obtain a reaction solution containing the product 3-hexyne-2,5-diol.

[0025] As Figure 2 shown, the process flow of the continuous flow reaction system of the present utility model for synthesizing 3-hexyne-2,5-diol includes the following steps:

[0026] S1. Prepare acetaldehyde gas through the acetaldehyde generator 1.

[0027] In this embodiment, when preparing acetaldehyde gas, commonly used 98% concentrated sulfuric acid is mixed and reacted with paraldehyde solution, and the addition amount of concentrated sulfuric acid is 0.05% of the mass of the paraldehyde solution.

[0028] S2. After the prepared acetaldehyde gas enters the gas booster 3 through the check valve container 2, the acetaldehyde gas is pressurized by the gas booster 3.

[0029] The pressure of the pressurized acetaldehyde gas needs to be consistent with the pressure of the introduced acetylene gas to avoid backflow caused by unbalanced pressure, resulting in unsuccessful reaction.

[0030] S3. Prepare the mixed solution 1 of xylene and catalyst, and add the mixed solution 1 to the mixing zone 41. At the same time, introduce acetylene gas into the mixing zone 41 to obtain the mixed solution 2 mixed with acetylene gas.

[0031] In this embodiment, the catalyst is potassium tert-butoxide, and the mixing mass ratio of xylene to catalyst is 15:1; acetylene gas is introduced through an acetylene cylinder, and the concentration of acetylene gas is the released concentration of the acetylene cylinder. The addition amount of acetylene gas is the release amount when the pressure is controlled at 0.15 MPa. Correspondingly, the acetaldehyde gas is pressurized to 0.15 MPa by the gas booster 3.

[0032] S4. When the mixed liquid mixed with acetylene gas enters the reaction zone 42, the pressurized acetaldehyde gas is simultaneously introduced into the reaction zone 42. The mixed liquid mixed with acetylene gas reacts with the acetaldehyde gas to obtain a reaction liquid containing the product 3-hexyne-2,5-diol.

[0033] In this embodiment, the mass ratio of xylene to acetaldehyde gas is 15:1. There are 2 microchannel reaction modules 5 in the mixing zone 41 for mixing, and 8 microchannel reaction modules 5 in the reaction zone 42 for reaction. The number of microchannel reaction modules 5 in the mixing zone 41 and the reaction zone 42 can be adjusted according to the actual situation of the reaction, so as to accurately control the reaction conditions through different combinations, enabling sufficient mixing and reaction between the reactants. The microchannel reactor 4 controls the reaction temperature of the mixed liquid mixed with acetylene gas and acetaldehyde gas to be 25°C - 30°C through its own heat exchanger.

[0034] In addition, in this embodiment, a stainless steel pump is connected to the channel inlet of the mixing zone 41 of the microchannel reactor 4, and a pressure controller 7 is connected to the channel outlet of the reaction zone 42. The mixed liquid of xylene and catalyst is pumped into the mixing zone 41 by the stainless steel pump. The stainless steel pump can adjust the conveying flow rate, thereby controlling the residence time of the reactants during the entire reaction process. At the same time, there are no moving parts in the fluid equipment of the reaction system, and the mixing reaction is only achieved through the conveying power of the pump, which can reduce production energy consumption; the pressure controller 7 can be used to control the pressure of the entire reaction. The reaction liquid of the obtained product 3-hexyne-2,5-diol is washed with water in the organic phase and then subjected to vacuum distillation to obtain the product 3-hexyne-2,5-diol (HD).

[0035] Through the continuous flow reaction system of the present utility model, the continuous flow reaction for synthesizing 3-hexyne-2,5-diol can be realized. At the same time, the reaction process can be strengthened, the contact time of the reactants can be reduced, and the reaction production cycle can be shortened, thereby reducing the generation of reaction by-products, ensuring the continuity of the reaction, and reducing production costs; during the reaction process, the reaction mixing uniformity can be improved, and the residence time of the reactants in each region can be accurately controlled, thereby avoiding the decomposition of reactants or products due to instability, increasing the reaction rate, expanding the selection range of process conditions, effectively controlling the process conditions of the synthesis route, and increasing the safety factor. Compared with the traditional kettle process for synthesizing 3-hexyne-2,5-diol, the continuous flow reaction system of the present utility model has the advantages of less liquid holdup in the reaction zone 42, accurate temperature control, process intensification, and no scale-up effect. At the same time, compared with the traditional batch process, adopting the continuous flow reaction process can essentially eliminate the safety hazards in the production of 3-hexyne-2,5-diol. The reaction production process is green and environmentally friendly, and seamless scale-up from small-scale experiments to industrialization can be achieved.

[0036] Although embodiments of the present utility model have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present utility model. The scope of the present utility model is defined by the appended claims and their equivalents.

Claims

1. A continuous flow reaction system for synthesizing 3-hexyne-2,5-diol, characterized in that: The invention comprises an acetaldehyde generator (1), a check container (2), a gas booster (3) and a microchannel reactor (4) which are connected in sequence. The microchannel reactor (4) comprises a mixing zone (41) and a reaction zone (42) which are connected in sequence. The mixing zone (41) and the reaction zone (42) both comprise a plurality of microchannel reaction modules (5) which are connected in sequence. The gas outlet of the gas booster (3) is connected to the channel inlet of the reaction zone (42).

2. A continuous flow reaction system for synthesizing 3-hexyne-2,5-diol according to claim 1, characterized in that: The acetaldehyde generator (1) comprises a round-bottom flask (11) and a dropping funnel (12). The top side wall of the round-bottom flask (11) is provided with a liquid inlet. The dropping funnel (12) is connected to the round-bottom flask (11) through the liquid inlet. The check container (2) is connected to the top bottle opening of the round-bottom flask (11).

3. A continuous flow reaction system for synthesizing 3-hexyne-2,5-diol according to claim 1, characterized in that: The non-return container (2) comprises a conical flask, the top opening of which is connected to the top opening of a round-bottom flask (11) via a condenser (6), and the gas inlet of a gas booster (3) is connected to the top side wall of the conical flask.

4. A continuous flow reaction system for synthesizing 3-hexyne-2,5-diol according to claim 1, characterized in that: The channel inlet of the mixing zone (41) is connected to a stainless steel pump.

5. A continuous flow reaction system for synthesizing 3-hexyne-2,5-diol according to claim 1, characterized in that: The channel outlet of the reaction zone (42) is connected to a pressure controller (7).

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