Synthetic method of methanedisulfonic acid

Abstract

The invention discloses a synthesis method of methane disulfonic acid, which comprises the following steps: (1) acidification reaction: under the action of a catalyst, methane disulfonate and an acidification reagent are subjected to acidification reaction to obtain a mixture containing methane disulfonic acid; the methanedisulfonate is sodium methanedisulfonate; and (2) purification: filtering the obtained mixture containing methanedisulfonic acid, carrying out first reduced pressure evaporation on the filtered filtrate, filtering when a solid is separated out and the liquid in the receiving bottle is not increased any more, and carrying out second reduced pressure evaporation on the filtrate to obtain high-purity methanedisulfonic acid. According to the synthesis method, the synthesis steps are simple and efficient, heavy metal ions are not introduced in the synthesis process, the synthesis method is environmentally friendly, the purity of the synthesized methanedisulfonic acid is as high as 99%, and the yield is high.

Description

Technical Field

[0001] This invention relates to the field of organic synthetic chemistry, and specifically to a method for synthesizing methane disulfonic acid. Background Technology

[0002] Methanedisulfonic acid, also known as methylene disulfonic acid, methyl disulfonic acid, and methanedisulfonic acid, has the molecular formula CH4O6S2. It is widely used as a main additive in hard chrome plating processes. Methylene methanedisulfonate, as an additive in lithium-ion battery electrolytes, can effectively improve the high-temperature cycle performance of batteries and increase their cycle life. Methanedisulfonic acid, as an intermediate in the synthesis of methylene methanedisulfonate, has great application potential.

[0003] Currently, there are several methods for synthesizing methane disulfonic acid: US2493038 reports the synthesis of methane disulfonic acid using methane and sulfur trioxide as raw materials and mercuric sulfate as a catalyst; CN106866465A and CN108516944A both use dichloromethane and sodium sulfite as raw materials to synthesize sodium methane disulfonate through a high-temperature and high-pressure reaction, followed by barium chloride bariumization and sulfuric acid acidification to obtain an aqueous solution of methane disulfonic acid, which is then concentrated and evaporated to obtain solid methane disulfonic acid; CN102887840A is similar to the previous two, also involving a high-temperature and high-pressure reaction followed by bariumization and acidification to obtain an aqueous solution of methane disulfonic acid. One method involves vacuum distillation, adding an organic solvent and dehydrating agent when the system contains 8-10% water, followed by filtration and washing to obtain a solid methanedisulfonic acid with low water content. CN104487417B involves reacting sulfites such as calcium sulfite and barium sulfite with dichloromethane to obtain a mixture containing methanedisulfonates. After acidification, a mixed solution of methanedisulfonic acid is obtained, filtered, concentrated, decolorized, and then frozen to crystallize. After filtration, an aqueous solution of methanedisulfonic acid is obtained. The inventor of this patent attempted to prepare it from its sodium or potassium salts using ion exchange, but found that this method only yielded a mixture of methanedisulfonic acid and its salts. These inventions either produce difficult-to-separate mixtures, resulting in impure methanedisulfonic acid; require more than three reaction steps, reducing the overall reaction yield; or introduce heavy metal ions that are difficult to remove during the reaction. Summary of the Invention

[0004] To address the aforementioned technical problems, the present invention aims to provide a method for synthesizing methane disulfonic acid. Compared to the existing three-step reaction of sulfonation-bariumization-acidification, the synthesis method of the present invention is simple and efficient, does not introduce heavy metal ions during the synthesis process, is environmentally friendly, and produces methane disulfonic acid with a purity of up to 99% and a high yield.

[0005] To achieve the above-mentioned technical objectives and effects, the present invention is implemented through the following technical solution:

[0006] A method for synthesizing methane disulfonic acid includes the following steps:

[0007] (1) Acidification reaction: Under the action of a catalyst, methane disulfonate reacts with an acidifying agent to obtain a mixture containing methane disulfonate; the methane disulfonate is sodium methane disulfonate;

[0008] (2) Purification: Filter the mixture containing methane disulfonic acid, and perform a first de-evaporation on the filtrate. When solids precipitate out and the liquid in the receiving bottle no longer increases, filter the filtrate and perform a second de-evaporation to obtain high-purity methane disulfonic acid.

[0009] Furthermore, the acidification reaction is carried out in water or a polar solvent or a mixture of both.

[0010] Preferably, the catalyst is at least one of tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium hydrogen sulfate, dodecyltrimethylammonium chloride, and tetradecyltrimethylammonium chloride.

[0011] Furthermore, the amount of catalyst added is 2-10% of the mass of methane disulfonate.

[0012] Preferably, the acidifying agent is at least one of sulfuric acid, hydrochloric acid, and nitric acid.

[0013] More preferably, the acidifying agent is hydrochloric acid.

[0014] Furthermore, the molar ratio of the methane disulfonate to the acidifying agent is 1:(0.6-8).

[0015] Furthermore, the acidification reaction is carried out at a temperature of 0-100°C.

[0016] Furthermore, the acidification reaction takes 1-24 hours.

[0017] Furthermore, the temperature of the first evaporation is 60-100℃ and the vacuum degree is 20-50kPa; the temperature of the second evaporation is 140-160℃ and the vacuum degree is 10-100Pa.

[0018] The beneficial effects of this invention are:

[0019] Compared with the prior art, the synthesis method of the present invention uses sodium methanedisulfonate and acidifying reagent as raw materials. Under the action of a catalyst, a mixture containing methanedisulfonic acid is obtained through a one-step acidification reaction. Then, high-purity and high-yield methanedisulfonic acid is obtained through two vacuum distillations under specific conditions.

[0020] Compared with the prior art, the synthesis method of the present invention uses sodium methane disulfonate and acidifying reagent as raw materials. The raw materials are readily available, the preparation process does not require barium treatment or other steps, the steps are simple, the production cost is low, there are no heavy metal ions, and there is no pollution to the environment.

[0021] This invention effectively separates methanedisulfonic acid from a mixture through specific purification steps, yielding high-purity methanedisulfonic acid.

[0022] The purity of the methane disulfonic acid synthesized by this invention can reach over 99%, and the yield can reach over 75%. Attached Figure Description

[0023] Figure 1 This is an ion chromatogram of methane disulfonic acid from Example 1 of the present invention. Detailed Implementation

[0024] The technical solutions of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] This invention provides a method for synthesizing methane disulfonic acid, comprising the following steps:

[0026] (1) Acidification reaction: Under the action of a catalyst, methane disulfonate reacts with an acidifying agent to obtain a mixture containing methane disulfonate; the methane disulfonate is sodium methane disulfonate;

[0027] (2) Purification: Filter the mixture containing methane disulfonic acid, and perform a first de-evaporation on the filtrate. When solids precipitate out and the liquid in the receiving bottle no longer increases, filter the filtrate and perform a second de-evaporation to obtain high-purity methane disulfonic acid.

[0028] The acidification reaction is carried out in water, a polar solvent, or a mixture of both, preferably in water.

[0029] The catalyst is at least one of tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium hydrogen sulfate, dodecyltrimethylammonium chloride, and tetradecyltrimethylammonium chloride. The amount of catalyst added is 2-10% of the mass of methane disulfonate, preferably 5%.

[0030] The acidifying agent is at least one of sulfuric acid, hydrochloric acid, and nitric acid, and is more preferably hydrochloric acid.

[0031] The molar ratio of the methane disulfonate to the acidifying agent is preferably 1:(0.6-8), more preferably 1:(2-3), and even more preferably 1:(2.1-2.5).

[0032] The acidification reaction temperature is preferably 0-100℃, more preferably 0-60℃, and even more preferably 30-40℃. The acidification reaction time is preferably 1-24 hours, more preferably 2-8 hours, and even more preferably 3-5 hours.

[0033] The temperature for the first evaporation is 60-100℃, and the vacuum degree is 20-50kPa; the temperature for the second evaporation is 140-160℃, and the vacuum degree is 10-100Pa.

[0034] The present invention will be further described in detail below through specific embodiments.

[0035] Example 1

[0036] Dissolve 20g of sodium methanedisulfonate in 100g of deionized water in a 250mL flask, stir, and add 1g of tetrabutylammonium chloride. Once the solution becomes clear, add 22.1g of 33% hydrochloric acid dropwise over 10 minutes at 35℃. Stop the acidification reaction after 4 hours; the solution should still be clear at this point. Filter the solution, yielding 136.5g of filtrate. Pour the filtrate into a 250mL flask and subject it to reduced-pressure evaporation. Set the temperature to 80℃ and apply a primary vacuum (50kPa). When solid precipitates and the liquid level in the receiving flask stops increasing, filter. The filtrate is then measured to be a 20% aqueous solution of methanedisulfonate. Continue reduced-pressure evaporation, setting the temperature to 160℃ and applying a tertiary vacuum (100Pa). Collect 12.5g of crystalline solid, which is the product, methanedisulfonate. Sampling analysis revealed that the purity of methanedisulfonic acid was 99.3%, and the reaction yield was 78.2%. The ion chromatogram of the prepared methanedisulfonic acid is shown below. Figure 1 As shown.

[0037] Example 2

[0038] Dissolve 20g of sodium methanedisulfonate in 100g of deionized water in a 250mL flask, stir, and add 1g of tetrabutylammonium chloride. Once the solution becomes clear, add 20g of 33% hydrochloric acid dropwise over 10 minutes at 35℃. Stop the acidification reaction after 4 hours; the solution should still be clear at this point. Filter the solution, yielding 133.4g of filtrate. Pour the filtrate into a 250mL flask and subject it to reduced-pressure evaporation. Set the temperature to 80℃ and apply a primary vacuum (50kPa). Filter when solid precipitates and the liquid level in the receiving flask stops increasing. Continue reduced-pressure evaporation, setting the temperature to 160℃ and applying a tertiary vacuum (100Pa). Collect 12.1g of crystalline solid, which is the product, methanedisulfonic acid. Sampling analysis shows that the purity of methanedisulfonic acid is 98.6%, and the reaction yield is 75.6%.

[0039] Example 3

[0040] Dissolve 20g of sodium methanedisulfonate in 100g of deionized water in a 250mL flask, stir, and then add 1g of tetrabutylammonium bromide. Once the solution becomes clear, add 22.1g of 33% hydrochloric acid dropwise over 10 minutes at 60℃. Stop the acidification reaction after 4 hours; the solution should still be clear at this point. Filter the solution, yielding 131.8g of filtrate. Pour the filtrate into a 250mL flask and subject it to reduced-pressure evaporation. Set the temperature to 80℃ and apply a primary vacuum (50kPa). Filter when solid precipitates and the liquid level in the receiving flask stops increasing. Continue reduced-pressure evaporation, setting the temperature to 160℃ and applying a tertiary vacuum (100Pa). Collect 12.2g of crystalline solid, which is the product, methanedisulfonic acid. Sampling analysis revealed a purity of 97.9% and a reaction yield of 76.2%.

[0041] Example 4

[0042] Dissolve 20g of sodium methanedisulfonate in 100g of deionized water in a 250mL flask, stir, and then add 0.4g of tetrabutylammonium chloride. Once the solution becomes clear, add 80.3g of 33% hydrochloric acid dropwise over 20 minutes at 60℃. Stop the acidification reaction after 4 hours; the solution should still be clear at this point. Filter the solution, yielding 188.2g of filtrate. Pour the filtrate into a 250mL flask and subject it to reduced-pressure evaporation. Set the temperature to 80℃ and apply a primary vacuum (50kPa). Filter when solid precipitates and the liquid level in the receiving flask stops increasing. Continue reduced-pressure evaporation, setting the temperature to 160℃ and applying a tertiary vacuum (100Pa). Collect 12.5g of crystalline solid, which is the product, methanedisulfonic acid. Sampling analysis shows that the purity of methanedisulfonic acid is 98.1%, and the reaction yield is 78%.

[0043] Example 5

[0044] Dissolve 20g of sodium methanedisulfonate in 100g of deionized water in a 250mL flask, stir, and then add 2g of tetrabutylammonium chloride. Once the solution becomes clear, add 22.1g of 33% hydrochloric acid dropwise over 10 minutes at 35℃. Stop the acidification reaction after 2 hours; the solution should still be clear at this point. Filter the solution, yielding 140.1g of filtrate. Pour the filtrate into a 250mL flask and subject it to reduced-pressure evaporation. Set the temperature to 80℃ and apply a primary vacuum (50kPa). Filter when solid precipitates and the liquid level in the receiving flask stops increasing. Continue reduced-pressure evaporation, setting the temperature to 160℃ and applying a tertiary vacuum (100Pa). Collect 11.3g of crystalline solid, which is the product, methanedisulfonic acid. Sampling analysis shows that the purity of methanedisulfonic acid is 97.5%, and the reaction yield is 70.9%.

[0045] Example 6

[0046] Dissolve 20g of sodium methanedisulfonate in 100g of deionized water in a 500mL flask, stir, and add 1g of tetrabutylammonium chloride. Once the solution becomes clear, add 9.1g of 98% concentrated sulfuric acid dropwise to 80g of water at 35℃ to prepare 10% sulfuric acid. Add the dilute sulfuric acid dropwise to the sodium methanedisulfonate solution over 10 minutes, stopping the acidification reaction after 4 hours. The solution should still be clear at this point. Filter the solution, yielding 205.6g of filtrate. Pour the filtrate into a 500mL flask and subject the filtrate to reduced evaporation. Set the temperature to 80℃ and apply a primary vacuum (50kPa). Filter when solid precipitates and the liquid level in the receiving flask stops increasing. Continue reduced evaporation, setting the temperature to 160℃ and applying a tertiary vacuum (100Pa). Collect 10.9g of crystalline solid, which is the product, methanedisulfonic acid. Sampling analysis revealed that the purity of methanedisulfonic acid was 97.2%, and the reaction yield was 68.3%.

[0047] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0048] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for synthesizing methane disulfonic acid, characterized in that, Includes the following steps: (1) Acidification reaction: Under the action of a catalyst, methane disulfonate reacts with an acidifying agent to obtain a mixture containing methane disulfonate; the methane disulfonate is sodium methane disulfonate; (2) Purification: Filter the mixture containing methane disulfonic acid, and perform a first de-evaporation on the filtrate. When solids precipitate out and the liquid in the receiving bottle no longer increases, filter the filtrate and perform a second de-evaporation to obtain high-purity methane disulfonic acid.

2. The method for synthesizing methane disulfonic acid according to claim 1, characterized in that, The acidification reaction is carried out in water, a polar solvent, or a mixture of both.

3. The method for synthesizing methane disulfonic acid according to claim 1, characterized in that, The catalyst is at least one of tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium hydrogen sulfate, dodecyltrimethylammonium chloride, and tetradecyltrimethylammonium chloride.

4. The method for synthesizing methane disulfonic acid according to claim 1, characterized in that, The catalyst is added at an amount of 2-10% of the mass of methane disulfonate.

5. The method for synthesizing methane disulfonic acid according to claim 1, characterized in that, The acidifying agent is at least one of sulfuric acid, hydrochloric acid, and nitric acid.

6. The method for synthesizing methane disulfonic acid according to claim 5, characterized in that, The acidifying agent is hydrochloric acid.

7. The method for synthesizing methane disulfonic acid according to claim 1, characterized in that, The molar ratio of the methane disulfonate to the acidifying agent is 1:(0.6-8).

8. The method for synthesizing methane disulfonic acid according to claim 1, characterized in that, The acidification reaction is carried out at a temperature of 0-100℃.

9. The method for synthesizing methane disulfonic acid according to claim 1, characterized in that, The acidification reaction takes 1-24 hours.

10. The method for synthesizing methane disulfonic acid according to claim 1, characterized in that, The temperature for the first evaporation is 60-100℃, and the vacuum degree is 20-50kPa; the temperature for the second evaporation is 140-160℃, and the vacuum degree is 10-100Pa.

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