Continuous production system of 1, 3-propane sultone

Abstract

The utility model provides a continuous production system of 1, 3-propane sultone, which comprises a synthesis unit, a nanofiltration separation unit, a cation exchange unit, a falling film concentration unit and a molecular distillation unit which are sequentially communicated through fluid, the synthesis unit accurately controls reaction conditions by adopting a pipeline reactor, continuous feeding and continuous reaction are realized, and the yield of 1, 3-propane sultone is improved. The nanofiltration separation unit adopts nanofiltration equipment to realize rapid separation of products with different molecular weights and small molecular substances, the system safety is improved, the cation exchange unit obtains a 3-hydroxypropanesulfonic acid aqueous solution through a resin tower, and then the 3-hydroxypropanesulfonic acid aqueous solution is evaporated and concentrated through a falling-film evaporator of the falling-film concentration unit; the concentrated solution is fed into a molecular distiller of the molecular distillation unit for esterification distillation, the product is uniformly heated, the heating time is short, the quality of the 1, 3-propane sultone product is improved, the byproduct production rate is reduced, and safe and continuous production is realized.

Description

Technical Field

[0001] This utility model relates to the field of 1,3-propanesulfonate lactone production technology, and in particular to a continuous production system for 1,3-propanesulfonate lactone. Background Technology

[0002] 1,3-Propane sulfonate lactone (1,3-PS) is a highly efficient sulfonylating agent. Its cyclic sulfonate groups exhibit high reactivity, making it important in organic synthesis. Industrially, 1,3-PS is widely used not only in the synthesis of electroplating intermediates, dye dispersants, and ink resins, but also in pharmaceutical chemistry for constructing sulfonic acid drug carriers (such as the prodrug of the antiviral agent tenofovir). In recent years, with the explosive growth of the new energy industry, high-purity 1,3-PS (acidity <20ppm, moisture <50ppm) has become a valuable additive in lithium-ion battery electrolytes, effectively improving electrode / electrolyte interface stability and increasing battery cycle life and storage stability.

[0003] However, current industrial production is still dominated by the batch method, and its inherent defects seriously restrict industrial upgrading: (1) Quality consistency bottleneck: batch feeding error (±5%) and uneven mass transfer in the reactor lead to product acidity fluctuations of up to 50-200ppm, which is difficult to meet the battery-grade purity requirements; (2) Efficiency and safety contradiction: the single batch reaction-purification cycle exceeds 12 hours, and involves manual operation of high-risk materials such as thiocyanate (highly toxic, LD50=25mg / kg) and acrylate (flammable and explosive); (3) Rising environmental protection costs: about 3.5 tons of sulfur-containing wastewater are generated per ton of product, and the energy consumption for waste gas treatment accounts for about 18% of the production cost. In the face of the continuous growth of global demand for 1,3-PS and the stringent requirements for material consistency in high-end application scenarios, the development of a full-process continuous production system has become an urgent need for the industry. Chinese patent application CN207623763U discloses an automatic control production system for 1,3-propanesulfonate lactone. This system uses sensors, motors, heaters, nitrogen replacement valves, tail gas emission valves, and a PLC controller installed on the 1,3-propanesulfonate lactone production unit to form a control loop. This achieves fully automatic and precise control of the raw material supply, reaction temperature, nitrogen replacement, and tail gas emission in the 1,3-propanesulfonate lactone production unit. However, it only involves automatic control of the reaction stage and cannot achieve continuous operation of the entire production system.

[0004] Therefore, it is of great significance to provide a continuous 1,3-propanesulfonate lactone production system to improve the production efficiency and safety of 1,3-propanesulfonate lactone, reduce personnel exposure, and achieve continuous clean production. Utility Model Content

[0005] In view of the above situation, this utility model provides a continuous production system for 1,3-propanesulfonate lactone, which improves production efficiency, increases production safety, reduces the incidence of side reactions, and improves product quality.

[0006] The technical solution to the problem solved by this utility model is as follows:

[0007] A continuous production system for 1,3-propanesulfonate lactone includes a synthesis unit, a nanofiltration separation unit, a cation exchange unit, a falling film concentration unit, and a molecular distillation unit that are sequentially fluidly connected.

[0008] The synthesis unit includes a pipeline reactor, which is provided with a premixed material inlet and an outlet.

[0009] The nanofiltration separation unit includes a nanofiltration device, which is provided with a material inlet, a dilute liquid outlet, and a concentrated liquid outlet. The material inlet is connected to the outlet of the pipeline reactor.

[0010] The cation exchange unit includes a resin tower, which has a concentrated liquid inlet and a 3-hydroxypropanesulfonic acid aqueous solution outlet, and the concentrated liquid inlet is connected to the concentrated liquid outlet of the nanofiltration device.

[0011] The falling film concentration unit includes a falling film evaporator, which has an inlet for a 3-hydroxypropanesulfonic acid aqueous solution and an outlet for a concentrate. The inlet for the 3-hydroxypropanesulfonic acid aqueous solution is connected to the outlet for the 3-hydroxypropanesulfonic acid aqueous solution of the resin tower.

[0012] The molecular distillation unit includes a molecular distillation apparatus, comprising a concentrate inlet and a 1,3-propanesulfonate outlet, wherein the concentrate inlet is connected to the concentrate outlet of the falling film evaporator.

[0013] In some embodiments of this utility model, the synthesis unit further includes a static mixer one and a static mixer two connected in sequence by pipelines; the static mixer one is provided with a sodium sulfite aqueous solution inlet, a sodium metabisulfite aqueous solution inlet and a mixed liquid outlet; the static mixer two is provided with a mixed liquid inlet, an allyl alcohol / catalyst system inlet and a premixed material outlet, the mixed liquid inlet is connected to the mixed liquid outlet of the static mixer one; the premixed material outlet is connected to the inlet of the pipeline reactor.

[0014] In some embodiments of this utility model, the nanofiltration device is provided with a return pipeline on the outside, which is used to return a portion of the concentrate output from the concentrate outlet to the nanofiltration device.

[0015] In some embodiments of this utility model, the falling film concentration unit further includes a falling film receiving tank. The inlet of the falling film receiving tank is connected to the concentrated liquid outlet of the falling film evaporator. The outlet pipeline of the falling film receiving tank is divided into two branches. The first branch is used to return part of the concentrated liquid to the falling film evaporator, and the second branch is used to transport the remaining concentrated liquid to the molecular distillation unit.

[0016] In some embodiments of this utility model, the falling film concentration unit further includes a gas-liquid separator, the inlet of which is connected to the light component outlet at the top of the falling film evaporator.

[0017] In some embodiments of this utility model, the gas-liquid separator is connected to a vacuum condenser system.

[0018] In some embodiments of this utility model, the molecular distillation unit further includes a heavy residue receiving tank and a product receiving tank. The heavy residue receiving tank is connected to the heavy component outlet at the bottom of the molecular distillation apparatus for collecting heavy components, and the product receiving tank is connected to the 1,3-propanesulfonate outlet of the molecular distillation apparatus for collecting products.

[0019] In some embodiments of this utility model, the molecular distillation unit further includes a condenser and a light component receiving tank. The inlet of the condenser is connected to the light component outlet at the top of the molecular distillation apparatus, and the outlet of the condenser is connected to the inlet of the light component receiving tank.

[0020] In some embodiments of this utility model, the condenser is connected to a vacuum system.

[0021] In some embodiments of this utility model, a delivery pump is provided on the outlet pipeline of the falling film receiving tank, and the delivery pump is located between the outlet of the falling film receiving tank and the node where the two branches are located.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The 1,3-propanesulfonate lactone continuous production system provided by this utility model achieves continuous feeding and continuous reaction by using a pipeline reactor to precisely control reaction conditions in the synthesis unit. The nanofiltration separation unit uses nanofiltration equipment to achieve rapid separation of products with different molecular weights and small molecules, avoiding the use of adding other hazardous chemicals to promote separation and improving system safety. By using a molecular distillation apparatus for simultaneous esterification and distillation, the product is heated uniformly and for a short time, which improves product quality and reduces by-product generation. This integrated continuous production system achieves safe and continuous production. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of a continuous production system for 1,3-propanesulfonate lactone according to an embodiment of the present invention.

[0025] Figure reference numerals: 1-Static mixer one; 2-Static mixer two; 3-Pipeline reactor; 4-Nanofiltration equipment; 5-Resin tower; 6-Falling film evaporator; 7-Falling film receiving tank; 8-Gas-liquid separator; 9-Molecular distillation apparatus; 10-Heavy residue receiving tank; 11-Product receiving tank; 12-Condenser; 13-Light component receiving tank. Detailed Implementation

[0026] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings.

[0027] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and are not intended to limit the scope of this invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of this invention, should still fall within the scope of the disclosed technical content. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of this invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of this invention.

[0028] This invention provides a continuous production system for 1,3-propanesulfonate lactone, see reference. Figure 1The system comprises a synthesis unit, a nanofiltration separation unit, a cation exchange unit, a falling film concentration unit, and a molecular distillation unit, which are sequentially fluidly connected. The synthesis unit includes a tubular reactor 3 with a premixed material inlet and a post-reaction material outlet. The nanofiltration separation unit includes a nanofiltration device 4 with a post-reaction material inlet, a dilute liquid outlet, and a concentrated liquid outlet; the post-reaction material inlet is connected to the post-reaction material outlet of the tubular reactor 3. The cation exchange unit includes a resin tower 5 with a concentrated liquid inlet and a 3-hydroxypropanesulfonic acid aqueous solution outlet; the concentrated liquid inlet is connected to the concentrated liquid outlet of the nanofiltration device 4. The falling film concentration unit includes a falling film evaporator 6 with a 3-hydroxypropanesulfonic acid aqueous solution inlet and a concentrated liquid outlet; the 3-hydroxypropanesulfonic acid aqueous solution inlet is connected to the 3-hydroxypropanesulfonic acid aqueous solution outlet of the resin tower 5. The molecular distillation unit includes a molecular distiller 9 with a concentrated liquid inlet and a 1,3-propanesulfonic acid lactone outlet; the concentrated liquid inlet is connected to the concentrated liquid outlet of the falling film evaporator 6. This invention's synthesis unit utilizes a pipeline reactor to precisely control reaction conditions, achieving continuous feeding and reaction of premixed materials. The nanofiltration separation unit employs nanofiltration equipment 4 to rapidly separate products of different molecular weights and small molecules from the post-reaction material, avoiding the use of hazardous chemicals to accelerate separation and improving system safety. The cation exchange unit uses resin tower 5 to convert the concentrated solution containing sodium 3-hydroxypropanesulfonate output from the nanofiltration equipment into an aqueous solution of 3-hydroxypropanesulfonic acid. The falling film concentration unit evaporates and concentrates the 3-hydroxypropanesulfonic acid aqueous solution to obtain a concentrated solution with a high concentration of 3-hydroxypropanesulfonic acid. The molecular distillation unit uses a molecular distiller 9 to perform esterification distillation on the concentrated 3-hydroxypropanesulfonic acid solution, resulting in uniform heating and short heating time, improving product quality and reducing by-product generation. This invention achieves safe and continuous production of 1,3-propanesulfonic acid lactone. Since this system requires operation under an inert atmosphere, inert gas purging is necessary before system operation. All related equipment and connections are existing technologies. The monitoring and control of pressure, pH, density, liquid level, temperature, etc. of each unit in the system of this utility model are all existing technologies and will not be described in detail here.

[0029] In some embodiments of this utility model, reference is made to Figure 1The synthesis unit further includes a static mixer 1 and a static mixer 2 connected in series by pipelines. Static mixer 1 has an inlet for sodium sulfite aqueous solution, an inlet for sodium metabisulfite aqueous solution, and a mixed liquid outlet. Static mixer 2 has an inlet for a mixed liquid, an inlet for an allyl alcohol / catalyst system, and a premixed material outlet. The mixed liquid inlet is connected to the mixed liquid outlet of static mixer 1. The premixed material outlet is connected to the premixed material inlet of the pipeline reactor 3. By connecting the two static mixers in series, the reactants are mixed continuously in stages, improving the controllability of the reaction and the flexibility of the process. In some preferred embodiments of this invention, a pH meter is installed on the connecting pipeline between static mixer 1 and static mixer 2 to adjust the pH of the mixed liquid to a suitable range, such as 7-9.

[0030] In some embodiments of this utility model, reference is made to Figure 1 The nanofiltration device 4 is equipped with a return pipeline on the outside, which is used to return part of the concentrate output from the concentrate outlet to the nanofiltration device 4.

[0031] In some embodiments of this utility model, the nanofiltration membrane of the nanofiltration device 4 is selected from polyamide membranes, sulfonated polyethersulfone membranes, or ceramic membranes with a molecular weight cutoff greater than 150, to ensure accurate separation effect and good mechanical strength and durability.

[0032] In some embodiments of this utility model, the resin tower 5 is filled with cation exchange resin, which is used to exchange cations with sodium 3-hydroxypropanesulfonate in the concentrate output from the nanofiltration device 4, thereby converting sodium 3-hydroxypropanesulfonate into an aqueous solution of 3-hydroxypropanesulfonic acid.

[0033] In some embodiments of this utility model, reference is made to Figure 1 The falling film concentration unit also includes a falling film receiving tank 7. The inlet of the falling film receiving tank 7 is connected to the concentrated liquid outlet of the falling film evaporator 6. The outlet pipeline of the falling film receiving tank 7 is divided into two branches. The first branch is used to return part of the concentrated liquid to the falling film evaporator 6, and the second branch is used to transport the remaining concentrated liquid to the molecular distillation unit 9. By adopting the reflux collection method, the concentration of 3-hydroxypropanesulfonic acid in the obtained concentrated liquid is higher.

[0034] In some embodiments of this utility model, reference is made to Figure 1 The falling film concentration unit further includes a gas-liquid separator 8. The inlet of the gas-liquid separator 8 is connected to the light component outlet at the top of the falling film evaporator 6 to remove droplets carried in the vapor, prevent droplets from entering the subsequent system, maintain a suitable liquid level in the falling film evaporator, and ensure stable falling film formation and evaporation effect. In some preferred embodiments of this invention, the gas-liquid separator 8 is connected to a vacuum condenser system for further condensing the gaseous light components into liquid.

[0035] In some embodiments of this utility model, reference is made to Figure 1 The molecular distillation unit further includes a heavy residue receiving tank 10 and a product receiving tank 11. The heavy residue receiving tank 10 is connected to the heavy component outlet at the bottom of the molecular distillation unit 9 and is used to collect heavy components. The product receiving tank 11 is connected to the 1,3-propanesulfonic acid lactone outlet of the molecular distillation unit 9 and is used to collect products.

[0036] In some embodiments of this utility model, reference is made to Figure 1 The molecular distillation unit further includes a condenser 12 and a light component receiving tank 13. The inlet of the condenser 12 is connected to the light component outlet at the top of the molecular distillation apparatus 9, and the outlet of the condenser 12 is connected to the inlet of the light component receiving tank 13, for further condensing the gaseous light components into a liquid. In some embodiments of this invention, the condenser 12 is connected to a vacuum system to lower the boiling point and facilitate condensation recovery.

[0037] In some embodiments of this utility model, reference is made to Figure 1 A delivery pump is provided on the outlet pipeline of the falling film receiving tank 7. The delivery pump is located between the outlet of the falling film receiving tank 7 and the node where the two branches are located, and provides delivery power. Preferably, the delivery pump can be selected from a plunger pump or a screw pump.

[0038] Working principle: This embodiment provides a continuous production system for 1,3-propanesulfonate lactone, such as... Figure 1As shown, solution A (sodium sulfite aqueous solution) and solution B (sodium metabisulfite aqueous solution) from metering pumps or flow meters are first mixed in static mixer 1. The pH is adjusted to 7-9 by a pH meter to obtain a mixed liquid. The mixed liquid is then mixed with solution C (allyl alcohol / catalyst system) from metering pumps or flow meters in static mixer 2 to obtain a premixed material, which is then fed into tubular reactor 3 for reaction. The reacted material is then pumped into nanofiltration equipment 4, where it is filtered... Small molecules such as water, allyl alcohol, sodium sulfite, and sodium bisulfite in the reacted material are separated from sodium 3-hydroxypropane sulfonate to obtain a dilute solution and a concentrated solution containing sodium 3-hydroxypropane sulfonate. The dilute solution is fed into a receiving tank, while a portion of the concentrated solution containing sodium 3-hydroxypropane sulfonate is refluxed to the nanofiltration unit 4 via the first branch, and the remainder enters the resin tower 5 via the second branch. In the resin tower, the concentrated solution containing sodium 3-hydroxypropane sulfonate undergoes cation exchange with the cation exchange resin to obtain an aqueous solution of 3-hydroxypropane sulfonic acid. A propane sulfonic acid aqueous solution enters falling film evaporator 6, which is heated by steam to obtain a concentrated 3-hydroxypropane sulfonic acid solution. The concentrated solution from the outlet of falling film evaporator 6 enters falling film receiving tank 7 for temporary storage. A transfer pump is installed on the outlet pipeline of falling film receiving tank 7. The pipeline then splits into two branches: the first branch recirculates a portion of the concentrated solution back to falling film evaporator 6, using a reflux extraction method to achieve a higher concentration of the 3-hydroxypropane sulfonic acid concentrate; the second branch transports the remaining concentrated solution to molecular distillation unit 9. The light components (solvent water, etc.) at the top of the falling film evaporator 6 are separated by the gas-liquid separator 8 and then sent to the vacuum condenser system. The 3-hydroxypropanesulfonic acid liquid after dehydration from the falling film evaporator 6 enters the molecular distillation unit 9, which is heated by steam. The residue (heavy components) flows into the heavy residue receiving tank 10. The product 1,3-propanesulfonyl lactone is condensed by condenser 12 (water condensation at 45°C) and enters the product receiving tank 11. The remaining light components are condensed by condenser 12 and then enter the light component receiving tank 13. The condenser 12 is connected to a vacuum system. The system operates in an inert gas atmosphere with continuous feeding and continuous discharging. The units are interlocked and regulated through pressure, pH, density, liquid level, and temperature monitoring and control.

[0039] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. A continuous production system for 1,3-propanesulfonate lactone, characterized in that, It includes a synthesis unit, a nanofiltration separation unit, a cation exchange unit, a falling film concentration unit, and a molecular distillation unit that are fluidly connected in sequence. The synthesis unit includes a pipeline reactor (3), which is provided with a premixed material inlet and a post-reaction material outlet; The nanofiltration separation unit includes a nanofiltration device (4), which is provided with a post-reaction material inlet, a dilute liquid outlet and a concentrated liquid outlet. The post-reaction material inlet is connected to the post-reaction material outlet of the pipeline reactor (3). The cation exchange unit includes a resin tower (5) which has a concentrated liquid inlet and a 3-hydroxypropanesulfonic acid aqueous solution outlet, the concentrated liquid inlet being connected to the concentrated liquid outlet of the nanofiltration device (4); The falling film concentration unit includes a falling film evaporator (6), which is provided with an inlet of 3-hydroxypropanesulfonic acid aqueous solution and a concentrated liquid outlet. The inlet of 3-hydroxypropanesulfonic acid aqueous solution is connected to the outlet of 3-hydroxypropanesulfonic acid aqueous solution of resin tower (5). The molecular distillation unit includes a molecular distillation apparatus (9) which has a concentrate inlet and a 1,3-propanesulfonate outlet, the concentrate inlet being connected to the concentrate outlet of the falling film evaporator (6).

2. The continuous production system for 1,3-propanesulfonate lactone according to claim 1, characterized in that, The synthesis unit also includes a static mixer one (1) and a static mixer two (2) connected in sequence by pipelines; the static mixer one (1) is provided with a sodium sulfite aqueous solution inlet, a sodium metabisulfite aqueous solution inlet and a mixed liquid outlet; the static mixer two (2) is provided with a mixed liquid inlet, an allyl alcohol / catalyst system inlet and a premixed material outlet, the mixed liquid inlet is connected to the mixed liquid outlet of the static mixer one; the premixed material outlet is connected to the premixed material inlet of the pipeline reactor (3).

3. The continuous production system for 1,3-propanesulfonate lactone according to claim 2, characterized in that, A pH meter is installed on the connecting pipe between the static mixer one (1) and the static mixer two (2).

4. The continuous production system for 1,3-propanesulfonate lactone according to claim 1, characterized in that, The nanofiltration device (4) is provided with a return pipeline on the outside, which is used to return part of the concentrated liquid output from the concentrated liquid outlet to the nanofiltration device (4); and / or, the nanofiltration membrane of the nanofiltration device is selected from polyamide membrane, sulfonated polyethersulfone membrane or ceramic membrane with a molecular weight cutoff greater than 150; and / or, the resin tower (5) is filled with cation exchange resin.

5. The continuous production system for 1,3-propanesulfonate lactone according to claim 1, characterized in that, The falling film concentration unit also includes a falling film receiving tank (7), the inlet of which is connected to the concentrated liquid outlet of the falling film evaporator (6), and the outlet pipeline of the falling film receiving tank (7) is divided into two branches. The first branch is used to return part of the concentrated liquid to the falling film evaporator (6), and the second branch is used to transport the remaining concentrated liquid to the molecular distillation unit (9); and / or, the falling film evaporator (6) adopts steam heat exchange.

6. The continuous production system for 1,3-propanesulfonate lactone according to claim 1, characterized in that, The falling film concentration unit also includes a gas-liquid separator (8), the inlet of which is connected to the light component outlet at the top of the falling film evaporator (6).

7. The continuous production system for 1,3-propanesulfonate lactone according to claim 1, characterized in that, The molecular distillation unit also includes a heavy residue receiving tank (10) and a product receiving tank (11). The heavy residue receiving tank (10) is connected to the heavy component outlet at the bottom of the molecular distillation apparatus (9) for collecting heavy components. The product receiving tank (11) is connected to the 1,3-propanesulfonic acid lactone outlet of the molecular distillation apparatus (9) for collecting products.

8. The continuous production system for 1,3-propanesulfonate lactone according to claim 1, characterized in that, The molecular distillation unit also includes a condenser (12) and a light component receiving tank (13). The inlet of the condenser is connected to the light component outlet at the top of the molecular distillation apparatus (9), and the outlet of the condenser (12) is connected to the inlet of the light component receiving tank (13).

9. The continuous production system for 1,3-propanesulfonate lactone according to claim 8, characterized in that, The condenser (12) is connected to a vacuum system.

10. The continuous production system for 1,3-propanesulfonate lactone according to claim 5, characterized in that, A delivery pump is provided on the outlet pipeline of the falling film receiving tank (7), and the delivery pump is located between the outlet of the falling film receiving tank (7) and the nodes where the two branches are located.

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