Preparation method of 1, 3-propane sultone

Abstract

The invention provides a preparation method of 1, 3-propane sultone, which comprises the following steps: introducing an allyl alcohol aqueous solution, a sodium hydroxide aqueous solution, sulfur dioxide and a slow-release peroxide into a continuous fluid reactor, reacting to obtain a 3-hydroxy propane sodium sulfonate crude product, acidifying the crude product to obtain 3-hydroxy propane sulfonic acid, concentrating to remove water, separating out salt by using methanol, and filtering to obtain 1, 3-propane sultone. And finally carrying out reduced pressure distillation on the filtrate to obtain 1, 3-PS. The slow-release peroxide is used for replacing conventional hydrogen peroxide or benzoyl peroxide to serve as an initiator, the preparation process conditions of the slow-release peroxide are controlled, calcium peroxide is embedded through stearic acid firstly, then surface modification polydopamine is subjected to secondary embedding, and the slow-release peroxide of a special structure is obtained; the selectivity of the 3-hydroxypropane sodium sulfonate is obviously improved while the reaction efficiency is not excessively influenced, and the method has industrial advantages.

Description

Technical Field

[0001] The invention relates to the field of organic synthesis, and in particular to a method for preparing 1,3-propane sultone. Background Art

[0002] 1,3-Propanesultone (1,3-Propanesultone, 1,3-PS) is a colorless liquid or white crystal (melting point: 30-33°C). The lactone bond contained in the molecule can react with alcohols, phenols, thiols, amines, etc., and introduce the -(CH2)3SO3H group to atoms such as O, S, and N, thereby improving the water solubility of the compound. It is an important raw material for synthesizing surfactants. In addition, 1,3-PS, as a lithium-ion battery additive, can improve the high-temperature cycle life of the battery, inhibit battery gas production, and improve the storage stability of lithium-ion batteries. Therefore, 1,3-PS has a very broad application scenario and is a very important intermediate for organic synthesis. The demand in various industries is very large. A continuous fluid reactor is a device that continuously produces products. In this device, reactants are added to the reactor through a pipeline and mixed with other reactants to continuously produce products. The reaction efficiency and selectivity can be improved by controlling the flow rate, concentration and ratio of the reactants.

[0003] At present, there are many industrial synthesis methods for 1,3-PS, which are mainly divided into: allyl alcohol addition method, 1,3-propylene glycol substitution method, 3-chloro-1-propanol substitution method, etc. according to the raw material route.

[0004] At present, the raw materials of the main methods for producing 1,3-PS in China are: ① Allyl alcohol addition method: allyl alcohol, sodium bisulfite (or sodium metabisulfite), peroxide (hydrogen peroxide); ② 1,3-propylene glycol substitution method: 1,3-propylene glycol, hydrogen chloride gas, sodium sulfite, peroxide; ③ 3-chloro-1-propanol method: ② 1,3-propylene glycol, sodium sulfite, peroxide (hydrogen peroxide).

[0005] The more prominent problems are: ① Propylene alcohol addition method: slow reaction rate, low reaction selectivity, more by-product salts, more kettle residues, difficult post-treatment, and serious environmental pollution. ② 1,3-propylene glycol substitution method: hydrogen chloride gas in the raw material has harsh conditions, high equipment requirements, high risk, not suitable for large-scale production, and troublesome post-treatment of tail gas during production. ③ 3-chloro-1-propanol method, the raw materials are expensive and the temperature of this route is high, and the energy consumption is large. Therefore, it is urgent to find a new preparation method for 1,3-propane sultone that reduces by-product inorganic salts, increases or decreases the utilization rate of raw materials, and improves the yield of products.

[0006] CN115611851A discloses a method for preparing 1,3-propane sultone, comprising the following steps: S1. using bisulfite and allyl alcohol as raw materials and a mixed aqueous solution of hydrogen peroxide and persulfate as an initiator, reacting at 40-55°C for 1-3h to obtain 3-hydroxypropane sulfonate; S2. utilizing a bipolar membrane electrodialysis process to decompose the aqueous solution of 3-hydroxypropane sulfonate into an aqueous solution of 3-hydroxypropane sulfonic acid and an alkaline solution, wherein the aqueous solution of 3-hydroxypropane sulfonate, the aqueous solution of 3-hydroxypropane sulfonic acid and the alkaline solution are separated into different compartments by a bipolar membrane electrodialysis device; S3. after reducing the pressure and concentrating the aqueous solution of 3-hydroxypropane sulfonic acid, a vacuum cyclization reaction is performed to obtain 1,3-propane sultone. CN108218828A discloses a method for preparing 1,3-propane sultone, comprising the following steps: (1) allowing allyl alcohol and bisulfite to undergo a free radical addition reaction in the presence of an amine compound, an initiator and water to generate 3-hydroxypropane sulfonate, and acidifying to prepare 3-hydroxypropane sulfonic acid; and (2) then allowing the 3-hydroxypropane sulfonic acid to undergo a cyclization reaction at a vacuum degree of 0-10 mmHg and a temperature of 150-200° C. to generate 1,3-propane sultone.

[0007] The above patents generally use peroxide to initiate the reaction. Allyl alcohol as a reaction raw material has selectivity for the reaction site. The reaction conditions are difficult to control and are prone to produce by-products, such as 3-(((3-hydroxypropyl)sulfonyl)oxy)propane-1-sulfonic acid, 1,6-hexanediol, etc. The target product 1,3-propane sultone has poor selectivity.

[0008] In order to improve the selectivity of the target product, CN117756778A discloses a method for preparing 1,3-propane sultone, which is a method for preparing 1,3-propane sultone by reacting allyl alcohol with sulfur dioxide under the action of a catalyst and an auxiliary agent. The auxiliary agent is an iodinated alkane or hydrogen iodide; the preparation method of the catalyst comprises the following steps: S1: adding a palladium salt to dioxane, slowly dropping a tetrafluoroboric acid-ether adduct after the palladium salt is completely dissolved, layering after the reaction is completed, washing and drying the supernatant to obtain a solid; S2: dissolving the solid obtained in S1 in an organic solvent, and then adding a ligand to obtain a catalyst. This patent uses a specific catalyst, which simultaneously improves the conversion rate of allyl alcohol and the selectivity of the target product. However, the synthesis process of the catalyst is complicated and is not suitable for large-scale industrial production. Summary of the invention

[0009] In order to solve the above-mentioned defects in the prior art, the present invention provides a preparation method of 1,3-propane sultone (1,3-PS), with mild reaction conditions, high raw material utilization rate and few by-products. An allyl alcohol aqueous solution, a sodium hydroxide aqueous solution, sulfur dioxide and a slow-release peroxide are introduced into a continuous fluid reactor for reaction to obtain a crude product of 3-hydroxypropane sodium sulfonate, and then a feed solution containing 3-hydroxypropane sodium sulfonate is introduced into a continuous fluid reactor containing hydrogen ions or an ion exchange resin for acidification to obtain a crude product of 3-hydroxypropane sulfonic acid, and then the 3-hydroxypropane sulfonic acid is concentrated and dehydrated, and methanol is used for salt precipitation and filtration, and the filtrate is finally distilled under reduced pressure to obtain 1,3-PS. The invention uses a slow-release peroxide to replace conventional hydrogen peroxide or benzoyl peroxide as an initiator, controls the preparation process conditions of the slow-release peroxide, first embeds calcium peroxide with stearic acid, and then performs secondary embedding by surface-modifying polydopamine, thereby obtaining a slow-release peroxide with a special structure, which significantly improves the selectivity of sodium 3-hydroxypropane sulfonate without excessively affecting the reaction efficiency, and has industrial advantages.

[0010] The object of the present invention is to provide a method for preparing 1,3-propane sultone, comprising the following steps:

[0011] (S1) introducing an allyl alcohol aqueous solution containing a sustained-release peroxide, an alkali metal hydroxide aqueous solution, and sulfur dioxide into a continuous flow reactor to react and obtain a crude product of sodium 3-hydroxypropane sulfonate; the sustained-release peroxide is obtained by first embedding calcium peroxide with stearic acid and then surface-modifying it with polydopamine;

[0012] (S2) introducing the crude sodium 3-hydroxypropane sulfonate obtained in step (S1) into an ion exchange resin and acidifying it for a period of time to obtain a crude 3-hydroxypropane sulfonic acid product;

[0013] (S3) after the crude aqueous solution of 3-hydroxypropane sulfonic acid in step (S2) is collected, the aqueous solution is concentrated to remove water, alcohol is added for salting out, the mixture is stirred and then filtered, and the filtrate is concentrated to obtain 3-hydroxypropane sulfonic acid;

[0014] (S4) 3-Hydroxypropane sulfonic acid can be distilled under reduced pressure to obtain the product 1,3-propane sultone.

[0015] Furthermore, in step (S1), the sustained-release peroxide is prepared by a preparation method comprising the following steps: stearic acid is dissolved in an organic solvent, mixed with calcium peroxide, fully mixed under stirring conditions, and dried to obtain stearic acid-embedded calcium peroxide particles; then the stearic acid-embedded calcium peroxide particles are dispersed in an aqueous solution of dopamine hydrochloride, the pH is adjusted to be weakly alkaline, stirred for sufficient reaction, solid-liquid separation, solid phase washing, and drying to obtain a sustained-release peroxide.

[0016] Furthermore, in the preparation of the sustained-release peroxide, the organic solvent is selected from at least one of chloroform, carbon tetrachloride and toluene, the mass ratio of stearic acid to calcium peroxide is 1:0.8-1.2, the concentration of the dopamine hydrochloride aqueous solution is 1-5wt%, and the ratio of the dopamine hydrochloride aqueous solution to the calcium peroxide particles embedded with stearic acid is 100mL:5-10g; the pH is adjusted to be weakly alkaline to adjust the pH to 8-10, preferably 8.5-9. Solid-liquid separation, washing and drying are not particularly limited and are well known in the art.

[0017] Furthermore, in step (S1), the concentration of the allyl alcohol aqueous solution is 50-70%wt, the amount of the sustained-release peroxide is 0.2-0.5wt% of the mass of the allyl alcohol; and the concentration of the alkali metal hydroxide aqueous solution is 10-30wt%.

[0018] Furthermore, in step (S1), the molar ratio of allyl alcohol alkali metal hydroxide to sulfur dioxide is 1:1.5-3:1.5-3, preferably 1:1.8-2.2:2-2.4. The alkali metal hydroxide is sodium hydroxide and / or potassium hydroxide.

[0019] Furthermore, in step (S1), the speed of introducing the allyl alcohol aqueous solution containing the slow-release peroxide into the continuous flow reactor is 1-3 mL / min.

[0020] Furthermore, the ion exchange resin used for acidification in step (S2) is one of 732 cation exchange resin, IRC200Na strong acid cation exchange resin, and Lewatit S100 ion exchange resin; further, the type of acid used in the reactor during acidification is hydrochloric acid or sulfuric acid; and the hydrogen ion concentration range is 1-5 mol / L.

[0021] In step (S1), allyl alcohol is reacted with sulfur dioxide to obtain sodium 3-hydroxypropane sulfonate (step S1), and then acidified to obtain 3-hydroxypropane sulfonic acid (step S2), the reaction equation is as shown in Formula I:

[0022]

[0023] Furthermore, in step (S1), the reaction temperature is 20°C to 70°C, and the reaction time is 3 to 4 hours; in step (S2), the acidification reaction temperature is 40°C to 60°C, and the reaction time is 2 to 3 hours.

[0024] Furthermore, in step (S3), the alcohol used for salting out is one of methanol or ethanol; the volume is 3 to 6 times the volume of allyl alcohol when feeding; and the temperature is between 10°C and 30°C.

[0025] Furthermore, in step (S4), the temperature of the reduced pressure distillation is between 140-180° C., and the vacuum degree is ≤400 mbar.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] The large-scale industrial production method for obtaining 1,3-PS has low reaction selectivity, more kettle residues, more by-product salts, more serious environmental pollution, and large process equipment investment. The final result of such a production method is that the profit is small, which is not conducive to the long-term development of the enterprise. The continuous fluid reactor production process adopted by the present invention does not pass through too many kettles, and is continuously produced through three-step reactions, without the need to transfer kettles and feed in the process, which greatly simplifies the reaction device and process, and can obtain 1,3-PS with high selectivity and yield. In addition, the present invention uses slow-release calcium peroxide as an initiator, which can provide mild initiation conditions, improve the selectivity of the reaction, and will not significantly affect the efficiency of the reaction. The preparation method of the present invention can be effectively applied to the production of 1,3-PS, fully and effectively converting the raw materials into the target product continuously, and avoiding the generation of too many by-products, making the reaction and separation economical and efficient, and the obtained product has high yield and high purity, economical, environmentally friendly, and easy to realize industrialization. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the preparation process of the present invention.

[0029] Figure 2 This is the hydrogen nuclear magnetic resonance spectrum of 3-hydroxypropane sulfonic acid obtained in step 3 of Example 1.

[0030] Figure 3 The GC chromatogram of the product 1,3-propane sultone obtained in Example 1 is shown in FIG.

[0031] Figure 4 This is the hydrogen nuclear magnetic resonance spectrum of 3-hydroxypropane sulfonic acid obtained in step (S3) of Comparative Example 1. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments. The following embodiments are further explanations of the present invention and do not constitute a limitation of the present invention.

[0033] Preparation Example 1

[0034] 10 g of stearic acid was dissolved in 50 mL of chloroform, and 8 g of calcium peroxide was added and mixed under stirring conditions. After stirring for 5 hours, the mixture was dried to obtain calcium peroxide particles embedded with stearic acid. Then, 10 g of calcium peroxide particles embedded with stearic acid were dispersed in 80 mL of 2 wt% dopamine hydrochloride aqueous solution, the pH was adjusted to 8.5 with NaOH aqueous solution, the mixture was stirred and reacted for 2 hours, centrifuged and filtered, the solid phase was washed with ethanol, and vacuum dried to obtain sustained-release calcium peroxide.

[0035] Comparative Preparation Example 1

[0036] 10 g of stearic acid was dissolved in 50 mL of chloroform, and 8 g of calcium peroxide was added and mixed thoroughly under stirring conditions. After stirring for 5 hours, the mixture was dried to obtain calcium peroxide particles embedded with stearic acid.

[0037] Comparative Preparation Example 2

[0038] 10 g of calcium peroxide was dispersed in 200 mL of 2 wt% dopamine hydrochloride aqueous solution, the pH was adjusted to 8.5 with NaOH aqueous solution, stirred for full reaction for 2 h, centrifuged and filtered, the solid phase was washed with ethanol, and vacuum dried to obtain polydopamine-coated calcium peroxide.

[0039] Example 1

[0040] (S1) Prepare raw materials: Liquid A is a mixture of 240g of 70wt% allyl alcohol aqueous solution and 0.42g of sustained-release calcium peroxide prepared in Preparation Example 1; Liquid B is 1010g of 20% NaOH aqueous solution; Raw material C gas is 332.7g SO2 gas. When the temperature of the continuous flow reactor reaches 50°C, open the raw material regulating valves at the same time, and introduce A, B, and C into the continuous flow reactor at a rate of 1mL / min for liquid A, 4.2mL / min for liquid B, and 0.48L / min for gas C. All raw materials are added in 4h, and the reaction is continued for 1h.

[0041] (S2) The reaction is completed when the content of allyl alcohol is ≤0.1% by sampling liquid phase detection, and the crude product of 3-hydroxypropane sulfonic acid sodium aqueous solution is obtained. Then, the feed liquid is pumped into 732 cation exchange resin acidified with hydrochloric acid, and acidified at 40° C. for 5 hours. The reaction is completed when the content of 3-hydroxypropane sulfonic acid sodium is ≤1% by sampling liquid phase detection, and the crude product of 3-hydroxypropane sulfonic acid sodium aqueous solution is obtained.

[0042] (S3) The obtained crude 3-hydroxypropane sulfonic acid aqueous solution is concentrated to remove a certain amount of water, so that the water content of the crude 3-hydroxypropane sulfonic acid aqueous solution is about 30wt%, and then 160mL of 95% ethanol is added thereto to precipitate salt, and the mixture is stirred at 25°C for 2h, and then filtered to obtain a 3-hydroxypropane sulfonic acid ethanol aqueous solution. The obtained 3-hydroxypropane sulfonic acid ethanol aqueous solution is concentrated to remove ethanol and most of the water, so that the water content of the 3-hydroxypropane sulfonic acid aqueous solution is 15wt%.

[0043] (S4) placing the obtained 3-hydroxypropane sulfonic acid aqueous solution in a 250 mL single-mouth bottle, starting to reduce the pressure, and after the pressure in the bottle is stabilized at 400 mbar, starting to increase the temperature so that the temperature of the liquid in the bottle is 150±5° C., and the temperature of the thermometer at the 75° distillation joint is 50±5° C., which is the first fraction and is discarded; when the temperature of the thermometer at the 75° distillation joint is 102-105° C., starting to receive the product 1,3-propane sultone, a total of 326.7 g of the product is collected, with a GC content of 99.9%, and a yield of 92.4% based on the raw material allyl alcohol.

[0044] Figure 1 It is a schematic diagram of the preparation process of the present invention.

[0045] Figure 2 This is the hydrogen nuclear magnetic resonance spectrum of 3-hydroxypropane sulfonic acid obtained in step 3 of Example 1, which is obtained by spinning the 3-hydroxypropane sulfonic acid aqueous solution and then testing it with deuterated water as solvent.

[0046] Figure 3 This is the GC chromatogram of the product 1,3-propane sultone obtained in Example 1. The GC purity reaches 99.9%.

[0047] Example 2

[0048] The other conditions were the same as those in Example 1, except that the amount of sustained-release calcium peroxide prepared in Preparation Example 1 was 0.84 g. The final product, 1,3-propane sultone, had a GC content of 99.9% and a yield of 93.1%.

[0049] Example 3

[0050] Other conditions were the same as those in Example 1, except that the rate of liquid A was 3 mL / min, the rate of liquid B was 12.6 mL / min, and the rate of gas C was 1.44 L / min. The final product, 1,3-propane sultone, had a GC content of 99.8% and a yield of 91.7%.

[0051] Comparative Example 1

[0052] The other conditions were the same as those in Example 1, except that the sustained-release calcium peroxide prepared in Preparation Example 1 in step (S1) was replaced by the stearic acid-embedded calcium peroxide particles prepared in Comparative Preparation Example 1. The final product, 1,3-propane sultone, had a GC content of 98.4% and a yield of 92.1%.

[0053] Comparative Example 2

[0054] The other conditions were the same as those in Example 1, except that the sustained-release calcium peroxide prepared in Preparation Example 1 in step (S1) was replaced by the polydopamine-coated calcium peroxide prepared in Comparative Preparation Example 2. The final product, 1,3-propane sultone, had a GC content of 97.6% and a yield of 92.4%.

[0055] Comparative Example 3

[0056] Other conditions were the same as those in Example 1, except that in step (S1), liquid A was prepared by mixing 240 g of 70 wt% allyl alcohol aqueous solution and 0.3 g of hydrogen peroxide. The final product, 1,3-propane sultone, had a GC content of 95.8% and a yield of 92.7%.

[0057] Figure 2 This is the hydrogen nuclear magnetic resonance spectrum of 3-hydroxypropane sulfonic acid obtained in step (S3) of Example 1. Figure 4 This is the H NMR spectrum of 3-hydroxypropane sulfonic acid obtained in step (S3) of Comparative Example 1. It can be seen that Example 1 uses sustained-release calcium peroxide, and its selectivity is significantly better than that of Comparative Example 1.

Claims

1. A method for preparing 1,3-propane sultone, characterized in that: The following steps are involved: (S1) introducing an allyl alcohol aqueous solution containing a sustained-release peroxide, an alkali metal hydroxide aqueous solution, and sulfur dioxide into a continuous flow reactor to react and obtain a crude product of sodium 3-hydroxypropane sulfonate; the sustained-release peroxide is obtained by first embedding calcium peroxide with stearic acid and then surface-modifying it with polydopamine; (S2) introducing the crude sodium 3-hydroxypropane sulfonate obtained in step (S1) into an ion exchange resin and acidifying it for a period of time to obtain a crude 3-hydroxypropane sulfonic acid product; (S3) after the crude aqueous solution of 3-hydroxypropane sulfonic acid in step (S2) is collected, the aqueous solution is concentrated to remove water, alcohol is added for salting out, the mixture is stirred and then filtered, and the filtrate is concentrated to obtain 3-hydroxypropane sulfonic acid; (S4) 3-Hydroxypropane sulfonic acid can be distilled under reduced pressure to obtain the product 1,3-propane sultone.

2. The preparation method according to claim 1, characterized in that: In step (S1), the sustained-release peroxide is prepared by a preparation method comprising the following steps: dissolving stearic acid in an organic solvent, mixing with calcium peroxide, fully mixing under stirring conditions, and drying to obtain calcium peroxide particles embedded with stearic acid; Then, the calcium peroxide particles embedded with stearic acid are dispersed in the dopamine hydrochloride aqueous solution, the pH is adjusted to be weakly alkaline, stirred for sufficient reaction, solid-liquid separation, solid phase washing, and drying to obtain a sustained-release peroxide.

3. The preparation method according to claim 2, characterized in that: The organic solvent is selected from at least one of chloroform, carbon tetrachloride and toluene, the mass ratio of stearic acid to calcium peroxide is 1:0.8-1.2, the concentration of dopamine hydrochloride aqueous solution is 1-5wt%, and the ratio of dopamine hydrochloride aqueous solution to stearic acid-embedded calcium peroxide particles is 100mL:5-10g; adjusting the pH to be weakly alkaline is adjusting the pH to 8-10, preferably 8.5-9.

4. The preparation method according to claim 1, characterized in that: In step (S1), the concentration of the allyl alcohol aqueous solution is 50-70%wt, the amount of the sustained-release peroxide is 0.2-0.5wt% of the mass of the allyl alcohol; and the concentration of the alkali metal hydroxide aqueous solution is 10-30wt%.

5. The preparation method according to claim 1, characterized in that: In step (S1), the molar ratio of allyl alcohol alkali metal hydroxide to sulfur dioxide is 1:1.5-3:1.5-3, preferably 1:1.8-2.2:2-2.4; the alkali metal hydroxide is sodium hydroxide and / or potassium hydroxide.

6. The preparation method according to claim 1, characterized in that: In step (S1), the speed of introducing the allyl alcohol aqueous solution containing the slow-release peroxide into the continuous flow reactor is 1-3 mL / min.

7. The preparation method according to claim 1, characterized in that: The ion exchange resin used in the acidification in step (S2) is one of 732 cation exchange resin, IRC200 Na strong acid cation exchange resin, and Lewatit S100 ion exchange resin; further, the type of acid used in the reactor during acidification is hydrochloric acid or sulfuric acid; and the hydrogen ion concentration range is 1-5 mol / L.

8. The preparation method according to claim 1, characterized in that: In step (S1), the reaction temperature is 20°C to 70°C, and the reaction time is 3 to 4 hours; in step (S2), the acidification reaction temperature is 40°C to 60°C, and the reaction time is 2 to 3 hours.

9. The preparation method according to claim 1, characterized in that: In step (S3), the alcohol used for salting out is one of methanol or ethanol; the volume is 3 to 6 times the volume of allyl alcohol when feeding; and the temperature is between 10°C and 30°C.

10. The preparation method according to claim 1, characterized in that: In step (S4), the temperature of the reduced pressure distillation is between 140-180° C., and the vacuum degree is ≤400 mbar.

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