Synthesis device of 3-chloropropionaldehyde diethyl acetal

Abstract

The utility model relates to the technical field of synthesis devices, in particular to a synthesis device of 3-chloropropionaldehyde diethyl acetal, which comprises a precooling head tank, a reaction kettle, an acid-base kettle, a first suction filtration tank, an extraction kettle, a second suction filtration tank, a distillation kettle, a distillation tower, a condenser, a product tank, a buffer tank and a vacuum pump which are connected in sequence, a first conveying pipe is arranged at the lower end of the reaction kettle, and a glass window and a valve are arranged in the first conveying pipe; according to the method, the temperature is strictly controlled, related equipment is improved specially suitable for synthesis of 3-chloropropionaldehyde diethyl acetal, the purity of the final product is high, and the production time is shortened.

Description

Technical Field

[0001] This utility model relates to the field of synthesis apparatus technology, specifically to a synthesis apparatus for 3-chloropropanal diethyl acetal. Background Technology

[0002] Chloropropaldehyde diethanol acetal (calcium carbonate stabilizer, mainly supplied by Baolong), CAS: 35573-93-4, is an important organic compound mainly used in pesticide intermediates, pharmaceutical intermediates, and irritating flammable liquids. It has a boiling point of 84℃ (3.33kPa), a relative density of 0.995, and a refractive index of 1.4200. It is insoluble in water but soluble in alcohols and ethers. Its strong, pungent odor and the difficulty of separation during production have led to a long-term shortage in the domestic market.

[0003] Currently, there is no dedicated synthesis apparatus for 3-chloropropaldehyde diethyl acetal. Its synthesis mainly adopts conventional instruments and equipment, such as conventional reaction vessels. After synthesis, sodium bicarbonate powder is added to the reaction vessel to remove excess hydrogen chloride, and then distillation is carried out directly. On the one hand, the synthesis efficiency is low, and on the other hand, the distillation time is long and the product purity is low.

[0004] Therefore, it is necessary to study a dedicated synthesis apparatus for 3-chloropropaldehyde diethyl acetal in order to improve the purity of 3-chloropropaldehyde diethyl acetal, shorten production time, and provide a larger supply. Utility Model Content

[0005] To address the aforementioned problems, this invention provides a synthesis apparatus for 3-chloropropanal diethyl acetal. The apparatus comprises a pre-cooling high-level tank, a reaction vessel, an acid-base vessel, a first filtration tank, an extraction vessel, a second filtration tank, a distillation vessel, a distillation column, a condenser, a product tank, a buffer tank, and a vacuum pump, connected in sequence. Strict temperature control is implemented, and the relevant equipment has been specifically modified to adapt to the synthesis of 3-chloropropanal diethyl acetal, resulting in a high-purity final product and a shortened production time.

[0006] This invention provides a synthesis apparatus for 3-chloropropanal diethyl acetal, comprising a precooling high-level tank, a reaction vessel, an acid-base vessel, a first filtration tank, an extraction vessel, a second filtration tank, a distillation vessel, a distillation column, a condenser, a product tank, a buffer tank, and a vacuum pump connected in sequence; the lower end of the reaction vessel is provided with a first feed pipe, which is provided with a glass window and a valve.

[0007] A glass viewing window is installed in the first feed pipe so that the operator can easily observe the current state of the material. When the material is found to be light yellow, it indicates that impurities have entered the first feed pipe. At this time, the valve can be closed directly to prevent impurities from entering the subsequent series of devices. This can reduce the difficulty of subsequent product separation and improve product purity.

[0008] Furthermore, the precooling high-level tank is equipped with a first feed pipe and a second feed pipe, and the precooling high-level tank is equipped with a first temperature control device.

[0009] Furthermore, the reactor is equipped with a third feed pipe and a fourth feed pipe, the other end of the third feed pipe being connected to the lower end of the precooling high-level tank, and the reactor is equipped with a second temperature control device.

[0010] Furthermore, the other end of the first conveying pipe is connected to the acid-base reactor, the acid-base reactor is provided with a fifth feed pipe, and the acid-base reactor is provided with a third temperature control device.

[0011] The purpose of setting up a temperature control device is to strictly control the temperature of raw materials, reaction, and post-processing materials to be below 5°C, avoid side reactions, reduce the difficulty of subsequent product separation, and help improve yield and purity.

[0012] Furthermore, the lower end of the acid-base reactor is provided with an acid-base reactor drain pipe, which is equipped with a glass window and a valve. Below the acid-base reactor drain pipe is a first suction filtration tank. Below the first suction filtration tank is a second feed pipe, the other end of which is connected to the extraction reactor. The extraction reactor is equipped with a sixth feed pipe.

[0013] In some embodiments, the lower end of the extraction vessel is provided with an extraction vessel drain pipe, and the extraction vessel drain pipe is provided with a glass viewing window and a valve.

[0014] In some embodiments, the extraction vessel is further provided with a solid feed pipe, a drain pipe, and a buoy. The drain pipe is a flexible hose, and the buoy is fixed to one end of the drain pipe inside the extraction vessel. A drain outlet is provided above the buoy on the drain pipe. An extraction vessel drain pipe is provided at the lower end of the extraction vessel, and a valve is provided in the extraction vessel drain pipe.

[0015] One method is to observe the state of the material flowing out of the extraction vessel through a glass window, and use this as a basis to separate the product material from the aqueous phase; another method is to control the height of the drain pipe opening to always be in the water layer by using a buoy with a density between the material layer and the water layer, so that as much water as possible is discharged, and then a desiccant is added to remove water.

[0016] Furthermore, a second filtration tank is located below the extraction vessel's drain pipe, and a third feed pipe is located below the second filtration tank. The other end of the third feed pipe is connected to the distillation vessel.

[0017] Furthermore, the top of the distillation vessel is connected to the bottom of the distillation column, the top of the distillation column is connected to the inlet end of the condenser, the outlet end of the condenser is connected to the inlet end of the product tank, the outlet end of the product tank is connected to the inlet end of the buffer tank, and the outlet end of the buffer tank is connected to the vacuum pump.

[0018] In some embodiments, the distillation column is provided with conjugate ring packing.

[0019] Conjugate ring packing combines the advantages of annular and saddle-shaped packings. It employs a conjugate curved rib structure with outward-curved edges at both ends and a suitable length-to-diameter ratio. Contact points exist between packing elements or between the packing and the tower wall, preventing stacking and enhancing liquid aggregation and surface renewal. Its surface features raised or recessed areas, a compact structure, and numerous internal porous channels, enabling uniform liquid distribution, reducing residence time, and improving mass transfer efficiency.

[0020] The beneficial technical effects of this utility model are:

[0021] 1. This utility model provides a synthesis apparatus for 3-chloropropanal diethyl acetal. The apparatus comprises a precooling high-level tank, a reaction vessel, an acid-base vessel, a first filtration tank, an extraction vessel, a second filtration tank, a distillation vessel, a distillation column, a condenser, a product tank, a buffer tank, and a vacuum pump connected in sequence. It implements strict temperature control and has made special improvements to the related equipment to adapt to the synthesis of 3-chloropropanal diethyl acetal. The final product has high purity and the production time is shortened.

[0022] 2. A glass viewing window is provided, which allows the operator to directly observe and judge the state of the material, and separate impurities from the material by opening and closing the valve;

[0023] 3. A method of setting up a drain pipe, a float and a solid feed pipe in the extraction vessel is proposed, which can maximize the discharge of the aqueous phase. Then, a solid desiccant is used for drying, which can maximize the removal of dispersed water in the material layer. The solid desiccant is removed by suction filtration, which can significantly shorten the time required for subsequent distillation and improve the purity of the product.

[0024] 4. Install a distillation column and fill it with conjugate ring packing to further shorten the overall process time. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of the synthesis apparatus for 3-chloropropanal diethyl acetal according to this utility model.

[0026] Figure 2 This is a schematic diagram of the extraction vessel structure of the synthesis apparatus for 3-chloropropanal diethyl acetal according to this utility model.

[0027] Figure reference numerals: 11-First feed pipe, 12-Second feed pipe, 13-Pre-cooling high-level tank, 14-First temperature control kit, 15-Third feed pipe, 16-Fourth feed pipe, 17-Fifth feed pipe, 18-Sixth feed pipe, 21-Reaction vessel, 22-Second temperature control kit, 23-First glass window, 24-First conveying pipe, 31-Acid-base vessel, 32-Third temperature control kit, 33-Second glass window, 34-First suction filter cylinder, 35-... 41-Extraction vessel, 411-Solid feed pipe, 412-Drain pipe, 413-Buoy, 414-Drain outlet, 42-Third glass window, 43-Second suction filter cylinder, 44-Third feed pipe, 51-Distillation vessel, 52-Fourth temperature control kit, 53-Distillation column, 54-Condenser, 55-Fourth feed pipe, 61-Product tank, 62-First vacuum pipe, 63-Buffer tank, 64-Second vacuum pipe, 65-Vacuum pump. Detailed Implementation

[0028] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Identical components are indicated by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "upper," and "lower" used in the following description refer to directions in the accompanying drawings, and the terms "bottom surface," "top surface," "inner," and "outer" refer to directions toward or away from the geometric center of a specific component, respectively. Example 1

[0029] like Figure 1 As shown, the present invention discloses a synthesis apparatus for 3-chloropropanal diethyl acetal, comprising a feeding device, a reaction device, an acid-base device, an extraction device, a distillation device, and a vacuum device, the specific details of which are as follows:

[0030] The feeding device includes a first feed pipe 11, a second feed pipe 12, a precooling high-level tank 13, a first temperature control kit 14, a third feed pipe 15, a fourth feed pipe 16, a fifth feed pipe 17, and a sixth feed pipe 18. The first feed pipe 11 and the second feed pipe 12 are located at the upper end of the precooling high-level tank 13. The first feed pipe 11 is used for feeding ethanol, and the second feed pipe 12 is used for feeding hydrochloric acid. The first temperature control kit 14 is located outside the precooling high-level tank 13 and is used to control the temperature inside the precooling high-level tank 13. Temperature, one end of the third feed pipe 15 is set at the lower end of the precooling high-level tank 13. The third feed pipe 15 is used to transport the ethanol-hydrochloric acid mixed solution in the precooling high-level tank 13 to the reaction vessel 21. The other end of the third feed pipe 15 and the fourth feed pipe 16 are set at the upper end of the reaction vessel 21. The fourth feed pipe 16 is used for feeding acrolein. The fifth feed pipe 17 is set at the upper end of the acid-base vessel 31. The fifth feed pipe 17 is used for feeding sodium bicarbonate solution. The sixth feed pipe 18 is set at the upper end of the extraction vessel 41 and is used for feeding water.

[0031] The reaction apparatus includes a reaction vessel 21, a second temperature control kit 22, a first glass window 23, and a first feed pipe 24. The second temperature control kit 22 is located outside the reaction vessel 21 and is used to control the internal temperature of the reaction vessel 21. The discharge port at the lower end of the reaction vessel 21 is connected to the first feed pipe 24. The first glass window 23 is provided on a section of the first feed pipe 24 that is close to the reaction vessel 21. The first glass window 23 is used to allow an observer to judge the current state of the material flowing out of the reaction vessel 21.

[0032] The acid-base device includes an acid-base vessel 31, a third temperature control kit 32, a second glass window 33, a first suction filter cylinder 34, and a second feed pipe 35. The third temperature control kit 32 is located outside the acid-base vessel 31 and is used to control the internal temperature of the acid-base vessel 31. The second glass window 33 is installed in the discharge pipe at the lower end of the acid-base vessel 31 and is used to allow the observer to judge the current state of the material flowing out of the acid-base vessel 31. Below the discharge pipe at the lower end of the acid-base vessel 31 is the first suction filter cylinder 34, and the bottom outlet of the first suction filter cylinder 34 is connected to the second feed pipe 35.

[0033] The extraction device includes an extraction vessel 41, a third glass window 42, a second suction filter cylinder 43, and a third feed pipe 44. The third glass window 42 is installed in the discharge pipe at the lower end of the extraction vessel 41. The third glass window 42 is used to allow the observer to judge the current state of the material flowing out of the extraction vessel 41. Below the discharge pipe at the lower end of the extraction vessel 41 is the second suction filter cylinder 43. The bottom outlet of the second suction filter cylinder 43 is connected to the third feed pipe 44.

[0034] The distillation apparatus includes a distillation kettle 51, a fourth temperature control kit 52, a distillation column 53, a condenser 54, and a fourth feed pipe 55. The fourth temperature control kit 52 is located outside the distillation kettle 51 and is used to regulate the temperature inside the distillation kettle 51. The top of the distillation kettle 51 is connected to the bottom of the distillation column 53, the top of the distillation column 53 is connected to the inlet of the condenser 54, and the outlet of the condenser 54 is connected to the fourth feed pipe 55.

[0035] The pressure reducing device includes a product tank 61, a first vacuum pipe 62, a buffer tank 63, a second vacuum pipe 64, and a vacuum pump 65. One end of the fourth feed pipe 55 is connected to the inlet end of the product tank 61, the outlet end of the product tank 61 is connected to one end of the first vacuum pipe 62, the other end of the first vacuum pipe 62 is connected to the inlet end of the buffer tank 63, the outlet end of the buffer tank 63 is connected to one end of the second vacuum pipe 64, and the other end of the second vacuum pipe 64 is connected to the vacuum pump 65.

[0036] The following is the working principle of the apparatus for synthesizing 3-chloropropanal diethyl acetal according to this invention:

[0037] Regarding feeding, the first feed pipe 11 is connected to the ethanol storage tank, the second feed pipe 12 is connected to the hydrochloric acid storage tank, the fourth feed pipe 16 is connected to the acrolein storage tank, the fifth feed pipe 17 is connected to the saturated sodium bicarbonate solution storage tank, and the sixth feed pipe 18 is connected to the water storage tank. The feed pipes are equipped with feed valves by default. Opening the relevant feed valves allows ethanol and hydrochloric acid to enter the pre-cooling high-level tank 13. The cooling function of the first temperature control kit 14 is activated. When the temperature measuring module of the first temperature control kit 14 detects that the material in the pre-cooling high-level tank 13 is below 5°C, the feed valve of the third feed pipe 15 is opened. Under the action of gravity, the material in the pre-cooling high-level tank 13 flows into the reactor 21. At the same time, the cooling function of the second temperature control kit 22 is activated to keep the internal temperature of the reactor 21 below 5°C.

[0038] Regarding the reaction, after the above feeding is completed, the feed valve of the fourth feed pipe 16 is opened. The valve has a flow rate control function by default. When controlling the flow rate of acrolein, the internal temperature of the reactor 21 is kept below 5°C. When the acrolein feed is started, the stirring paddle in the reactor 21 is turned on. After the current batch of acrolein is fed, the reaction is carried out for a period of time, and then the valve of the first feed pipe 24 is opened. The feed pipes in this utility model are equipped with valves and pumps by default. The material after the reaction is completed flows out of the reactor 21. At this time, the operator observes the first glass window 23. The upper layer inside the reactor 21 is an ethanol mixture layer, which is slightly yellow in appearance, and the lower layer is the material layer, which is colorless in appearance. When yellow is observed in the glass window, the valve of the first feed pipe 24 is immediately closed. At this time, only the material layer is pumped into the acid-base reactor 31.

[0039] Regarding pH adjustment, firstly, activate the cooling function of the second temperature control kit 32 to keep the internal temperature of the acid-base reactor 31 below 5°C. Then, activate the agitator inside the acid-base reactor 31, open the valve of the fifth feed pipe 17, and control the flow rate of the saturated sodium bicarbonate solution. Record the amount of sodium bicarbonate fed. When the amount of feed recorded in the process is reached, close the valve of the fifth feed pipe 17. The agitator in the acid-base reactor 31 continues to stir for a period of time. Then, open the valve at the bottom of the acid-base reactor 31. The operator can observe the second glass window 33 to judge the state of the material. At the same time, the material in the acid-base reactor 31 enters the first suction filter cylinder 34 under the action of gravity. The first suction filter cylinder 34 is pre-laid with filter media, such as filter screen, filter cloth, or filter paper, before operation. The material is then filtered by the pump installed in the second feed pipe 35. The filtered solution is pumped into the extraction reactor 41.

[0040] Regarding extraction, open the valve of the sixth feed pipe 18 and control the water flow rate, record the water feed rate, and close the valve of the sixth feed pipe 18 when the feed rate recorded in the process is reached. The stirring paddle of the extraction vessel 41 stirs for a period of time, and then lets it stand for a period of time. Open the valve at the bottom of the extraction vessel 41, and the operator can observe the third glass window 42 to judge the material state. The liquid material in the extraction vessel 41 is divided into two layers. The upper layer is a water layer containing impurities, which is light yellow, and the lower layer is the material layer. When the third glass window 42 shows a light yellow color, close the valve at the bottom of the extraction vessel 41. The material layer enters the second suction filter cylinder 43. Similarly, the second suction filter cylinder 43 is pre-laid with filter media, such as filter screen, filter cloth or filter paper, before operation. The pump set in the third feed pipe 44 performs suction filtration, and the filtered solution is pumped into the distillation vessel 51.

[0041] Regarding vacuum distillation, valves in the relevant pipelines are closed and opened to ensure good airtightness and connectivity between the distillation apparatus and the vacuum device. The fourth temperature control kit 52 and vacuum pump 65 outside the distillation kettle 51 are opened. A lower temperature is set according to the vacuum level, and low-boiling-point impurities in the material inside the distillation kettle 51 are removed first. Then, a higher temperature is set to distill off the 3-chloropropanal diethyl acetal product. The distillation column 53 is used to separate substances with different boiling points, the condenser 54 is used to condense the vapor, the product tank 61 is used to collect the product, and the buffer tank 63 is used to prevent eddies from occurring under vacuum negative pressure and improve the stability of the production process.

[0042] After the above operations are completed, the relevant discharge valves and drain valves are opened to collect the product and clean up the waste. Three batches are produced in parallel, and the yields of the three batches are calculated. The yields of the three batches are all greater than 50%. The purity of the three batches of products is greater than 99% after high-performance liquid chromatography detection. Conventional production only involves reaction in a reactor followed by distillation, with a yield of about 30% and a purity of about 90%. Therefore, using the device of this invention for the synthesis of 3-chloropropaldehyde diethyl acetal can significantly improve the yield and purity of the product.

[0043] Furthermore, through the design of the device, this utility model divides the process into five stages: pre-cooling feeding, reaction, acid and alkali adjustment, extraction, and vacuum distillation. Therefore, it can carry out up to five batches of production operations simultaneously, significantly improving production efficiency. In practice, the inventors carried out three batches of production operations simultaneously. Compared with the above-mentioned conventional production, the total time in the test of producing 10kg of 3-chloropropaldehyde diethyl acetal was shortened by 72%. Example 2

[0044] The only difference from Example 1 is that the distillation column 53 is equipped with conjugate ring packing. This conjugate ring packing combines the advantages of annular and saddle-shaped packing, employing a conjugate curved rib structure with outward-curved edges at both ends and a suitable length-to-diameter ratio. The contact points between the packing elements or between the packing and the column wall prevent overlapping, thus enhancing liquid aggregation and surface renewal. Its surface features raised or recessed features, a compact structure, and porous internal channels, enabling uniform liquid distribution, reducing residence time, and improving mass transfer efficiency. Compared to Example 1, the total time in the production of 10 kg of 3-chloropropaldehyde diethyl acetal was reduced by 11%. Example 3

[0045] The only difference from Example 2 is that the extraction vessel 41 has the following features: Figure 2 As shown in the structure, the extraction vessel 41 is also equipped with a solid feed pipe 411, a drain pipe 412, and a float 413. The drain pipe 412 is a flexible hose with a pump connected to the outside for pumping water and draining water. The float 413 has a specific density and can be suspended in the middle of the material layer and the water layer. Above the float 413 is the drain outlet 414 of the drain pipe 412. The solid feed pipe 411 is used to add potassium carbonate desiccant into the extraction vessel 41.

[0046] During operation, the drain pipe 412 is initially in the retracted state. The drain pipe 412 is a flexible tube that can be pulled outward along the opening on the side wall of the extraction vessel 41 to accommodate the drain pipe 412. The extraction operation in Example 1 is then performed. After standing for a period of time, the drain pipe 412 is placed into the extraction vessel 41. The float 413 ensures that the drain outlet 414 of the drain pipe 412 is always in the water layer. The pump is turned on to pump water. After completion, potassium carbonate desiccant is added using the solid feeding pipe 411 to keep the material layer dry. Finally, the bottom valve of the extraction vessel 41 is opened directly to discharge the dried material. The potassium carbonate can be removed during filtration.

[0047] After testing, the purity of 3-chloropropaldehyde diethyl acetal prepared using the synthesis apparatus of Example 3 was greater than 99.5%. Compared with Example 2, the total time in the production of 10 kg of 3-chloropropaldehyde diethyl acetal was shortened by 37%. This was because the moisture content in the product was reduced and the distillation substrate was dehydrated, thus improving the distillation efficiency.

[0048] The above description is merely a preferred embodiment of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions falling within the scope of this utility model's concept are protected. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should also be considered within the protection scope of this utility model.

Claims

1. An apparatus for synthesizing 3-chloropropanal diethyl acetal, characterized in that, It includes a precooling high-level tank, a reaction vessel, an acid-base vessel, a first filtration tank, an extraction vessel, a second filtration tank, a distillation vessel, a distillation column, a condenser, a product tank, a buffer tank, and a vacuum pump connected in sequence; the lower end of the reaction vessel is provided with a first conveying pipe, and the first conveying pipe is provided with a glass window and a valve.

2. The apparatus for synthesizing 3-chloropropanal diethyl acetal as described in claim 1, characterized in that, The precooling high-level tank is equipped with a first feed pipe and a second feed pipe, and the precooling high-level tank is equipped with a first temperature control device.

3. The apparatus for synthesizing 3-chloropropanal diethyl acetal as described in claim 2, characterized in that, The reactor is equipped with a third feed pipe and a fourth feed pipe. The other end of the third feed pipe is connected to the lower end of the precooling high-level tank. The reactor is also equipped with a second temperature control device.

4. The apparatus for synthesizing 3-chloropropanal diethyl acetal as described in claim 3, characterized in that, The other end of the first conveying pipe is connected to the acid-base reactor, which is equipped with a fifth feed pipe and a third temperature control device.

5. The apparatus for synthesizing 3-chloropropanal diethyl acetal as described in claim 4, characterized in that, The lower end of the acid-base reactor is provided with an acid-base reactor drain pipe, which is equipped with a glass window and a valve. Below the acid-base reactor drain pipe is a first suction filtration tank. Below the first suction filtration tank is a second feed pipe, the other end of which is connected to the extraction reactor. The extraction reactor is provided with a sixth feed pipe.

6. The apparatus for synthesizing 3-chloropropanal diethyl acetal as described in claim 5, characterized in that, The lower end of the extraction vessel is provided with an extraction vessel drain pipe, and the extraction vessel drain pipe is provided with a glass window and a valve.

7. The apparatus for synthesizing 3-chloropropanal diethyl acetal as described in claim 5, characterized in that, The extraction vessel is also equipped with a solid feed pipe, a drain pipe and a buoy. The drain pipe is a flexible hose. The buoy is fixed to one end of the drain pipe inside the extraction vessel. The drain pipe has a drain outlet above the buoy. The lower end of the extraction vessel is equipped with an extraction vessel drain pipe and a valve is installed in the extraction vessel drain pipe.

8. The apparatus for synthesizing 3-chloropropanal diethyl acetal as described in claim 6 or 7, characterized in that, Below the extraction vessel's drain pipe is a second filtration tank, and below the second filtration tank is a third feed pipe, the other end of which is connected to the distillation vessel.

9. The apparatus for synthesizing 3-chloropropanal diethyl acetal as described in claim 8, characterized in that, The top of the distillation vessel is connected to the bottom of the distillation column, the top of the distillation column is connected to the inlet of the condenser, the outlet of the condenser is connected to the inlet of the product tank, the outlet of the product tank is connected to the inlet of the buffer tank, and the outlet of the buffer tank is connected to the vacuum pump.

10. The apparatus for synthesizing 3-chloropropanal diethyl acetal as described in claim 9, characterized in that, The distillation column is equipped with conjugate ring packing.

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