A sodium polydisulfide dipropane sulfonate and its preparation method

Abstract

This invention discloses a sodium polydisulfide dipropane sulfonate and its preparation method, belonging to the field of organic synthesis technology. The preparation method of the sodium polydisulfide dipropane sulfonate includes the following steps: S1, mixing and reacting 1,3-propane sulfonyl lactone with a thiourea aqueous solution at 10-20°C to obtain isothiourea propane sulfonate inner salt; S2, neutralizing the isothiourea propane sulfonate inner salt with a sodium hydroxide aqueous solution at 25-35°C to obtain a sodium 3-mercaptopropane sulfonate aqueous solution, followed by oxidation with an oxidant to obtain a crude sodium polydisulfide dipropane sulfonate aqueous solution. The preparation method proposed in this invention avoids the use of ammonia and reduces costs.

Description

Technical Field

[0001] This invention relates to the field of organic synthesis technology, specifically to a sodium polydithiodipropane sulfonate and its preparation method. Background Technology

[0002] Sodium polydisulfide dipropane sulfonate (SPS), a multifunctional chemical, is a versatile fine chemical intermediate with wide applications in various industrial fields such as electroplating, new energy batteries, environmental protection, and pharmaceutical materials. It is primarily used in acidic copper plating as a brightener, refining the crystal structure of the plating layer and effectively increasing current density during the plating process. In the production of lithium-ion battery electrolytic copper foil, it is a crucial leveling and refining agent, inhibiting excessive copper foil thickness and improving surface smoothness to meet the requirements of lithium-ion batteries for extremely thin, high-tensile-strength copper foil.

[0003] Existing methods for synthesizing SPS mainly include: reacting sodium sulfide and sulfur powder to generate sodium disulfide, which is then reacted with 1,3-propanesulfonyl lactone to produce SPS; synthesizing SPS using sodium hydrosulfide and 1,3-propanesulfonyl lactone, followed by oxidation; and preparing SPS from 1,3-propanesulfonyl lactone via a disulfidation reaction. These methods share some common problems: numerous side reactions, low conversion rates, low purity, and stringent process requirements.

[0004] Therefore, developing a safe, efficient, and low-cost new process for SPS synthesis is of great significance. An ideal synthesis method should improve SPS purity, reduce impurity generation, lower production costs, and avoid the use of highly toxic substances and energy-intensive processes. This is crucial for meeting market demand for high-quality SPS and promoting its application in fields such as electrolytic copper foil and acid copper plating.

[0005] Several invention patents have been developed to address the issues of low product purity, low yield, and production process risks in the synthesis of sodium dithiopropane sulfonate.

[0006] Invention CN115611791A provides a method for preparing sodium polydisulfide dipropanesulfonate, comprising adding 1,3-propanesulfonyl lactone to a mixture of thiourea and a solvent to react and obtain 3-isothiourea propanesulfonic acid, followed by a neutralization reaction to obtain ammonium 3-mercaptopropanesulfonate, and then preparing high-purity sodium polydisulfide dipropanesulfonate through ion exchange and oxidation. However, this patent uses ammonia water as a reaction raw material, introducing ammonium ions, which leads to difficulties in post-treatment and generates a large amount of wastewater, resulting in high treatment costs. Furthermore, the reaction and purification processes use a large amount of solvent, leading to high processing costs and low product production efficiency. Summary of the Invention

[0007] The purpose of this invention is to overcome the above-mentioned technical deficiencies and provide a sodium polydisulfide dipropane sulfonate and its preparation method, solving the technical problem of how to avoid the use of ammonia and prepare sodium polydisulfide dipropane sulfonate at low cost in the prior art.

[0008] To achieve the above-mentioned technical objectives, the present invention provides a method for preparing sodium polydisulfide dipropane sulfonate, comprising the following steps: S1. 1,3-Propanesulfonyl lactone and thiourea aqueous solution are mixed and reacted at 10-20℃ to obtain isothiourea propanesulfonic acid inner salt; S2. The isothiourea propanesulfonic acid inner salt is neutralized with sodium hydroxide aqueous solution at 25-35°C to obtain sodium 3-mercaptopropanesulfonate aqueous solution. Then, an oxidizing agent is added for oxidation to obtain crude sodium polydithiopropanesulfonate aqueous solution.

[0009] In any implementation, step S2 is followed by step S3: The crude sodium polydisulfide dipropane sulfonate aqueous solution obtained in step S2 was filtered through a nanofiltration membrane to obtain purified sodium polydisulfide dipropane sulfonate.

[0010] In any embodiment, in step S1, the molar ratio of the 1,3-propanesulfonyl lactone to the thiourea in the thiourea aqueous solution is (0.95-1):1.

[0011] In any embodiment, in step S1, the 1,3-propanesulfonyl lactone and the thiourea aqueous solution are introduced into a tubular reactor for mixing and reaction.

[0012] In any embodiment, in step S2, the molar ratio of the isothiourea propanesulfonic acid inner salt to sodium hydroxide in the sodium hydroxide aqueous solution is 1:(1.2-2).

[0013] In any embodiment, in step S2, the oxidant is one or more of hydrogen peroxide, air, and oxygen.

[0014] In any embodiment, in step S3, the nanofiltration membrane is a nanomembrane made of aromatic polyamide with a molecular weight cutoff of 200-500 Da.

[0015] In any embodiment, in step S3, the nanofiltration membrane has a filtration pressure of 0.5-1.0 MPa and a temperature of 25-35°C.

[0016] In addition, the present invention also proposes a sodium polydisulfide dipropane sulfonate, which is prepared by the above preparation method.

[0017] Compared with the prior art, the beneficial effects of the present invention include: the present invention carries out the reaction at a lower reaction temperature, which can avoid the continuous accumulation and hydrolysis of 1,3-propanesulfonyl lactone, improve the yield of the reaction intermediate isothiourea propanesulfonic acid inner salt, and the absence of organic solvents in the reaction process can greatly reduce environmental pollution and raw material costs. The reaction has low energy consumption, short production cycle, and high production safety, thereby avoiding the use of ammonia and reducing costs.

[0018] In addition, purification is carried out using nanofiltration membranes. By utilizing the high efficiency of nanofiltration membranes in retaining divalent ions, sodium polydisulfide dipropane sulfonate is purified efficiently, improving purification efficiency, increasing product yield, and reducing production costs. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the tubular reactor used in Embodiment 1 of the present invention.

[0020] Figure 2 This is a schematic diagram of the nanofiltration membrane device used in Embodiment 1 of the present invention.

[0021] Figure 3 This is the 1H NMR spectrum of sodium polydisulfide dipropane sulfonate prepared in Example 1 of this invention. Detailed Implementation

[0022] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60~120 and 80~110 are listed for a specific parameter, it is also expected that ranges of 60~110 and 80~120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1~3, 1~4, 1~5, 2~3, 2~4, and 2~5. In this application, unless otherwise stated, the numerical range "a~b" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0~5" indicates that all real numbers between "0~5" have been listed in this article; "0~5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0023] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0024] Unless otherwise specified, the term "or" is inclusive in this application. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, the condition "A or B" is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0025] This specific embodiment provides a method for preparing sodium polydithiopropane sulfonate, comprising the following steps: S1. 1,3-Propanesulfonyl lactone and thiourea aqueous solution are mixed and reacted in a tubular reactor at 10-20°C for 1-1.5 h to obtain isothiourea propanesulfonic acid inner salt; the molar ratio of 1,3-propanesulfonyl lactone to thiourea in the thiourea aqueous solution is (0.95-1):1. S2. The isothiourea propanesulfonic acid inner salt is neutralized with an aqueous sodium hydroxide solution at 25-35°C for 2-3 hours to obtain an aqueous solution of sodium 3-mercaptopropanesulfonate. Then, an oxidizing agent is added for oxidation to obtain a crude aqueous solution of sodium polydisulfide dipropanesulfonate. The molar ratio of the isothiourea propanesulfonic acid inner salt to sodium hydroxide in the aqueous solution is 1:(1.2-2). The oxidizing agent is one or more of hydrogen peroxide, air, and oxygen. S3. The crude sodium disulfide dipropane sulfonate aqueous solution obtained in step S2 is filtered using a nanofiltration membrane to obtain purified sodium disulfide dipropane sulfonate. The nanofiltration membrane is a nanomembrane made of aromatic polyamide material with a molecular weight cutoff of 200-500 Da. The filtration pressure of the nanofiltration membrane is 0.5-1.0 MPa and the temperature is 25-35℃.

[0026] This specific embodiment also proposes a sodium polydithiodipropane sulfonate, which is prepared by the above preparation method.

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0028] In this invention, the terms "some embodiments," "this embodiment," and examples are used to describe a subset of all possible embodiments. However, it is understood that "some embodiments" can be the same subset or different subsets of all possible embodiments and can be combined with each other without conflict.

[0029] If the application documents contain similar descriptions such as "first / second", the following explanation shall be added: In the following description, the terms "first / second / third" are used only to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first / second / third" may be interchanged in a specific order or sequence where permitted, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein.

[0030] In this embodiment, the term "and / or" is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, object A and / or object B can represent three situations: object A exists alone, object A and object B exist simultaneously, and object B exists alone.

[0031] The following describes embodiments of this application. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all conventional products that can be obtained commercially.

[0032] Example 1

[0033] Combination Figure 1-2 This embodiment proposes a method for preparing high-purity sodium polydisulfide dipropane sulfonate, comprising the following steps: S1. 122g (1mol) of 1,3-propanesulfonyl lactone and 1mol of thiourea aqueous solution (76g of thiourea and 500g of water were mixed evenly to obtain thiourea aqueous solution) were introduced into a tubular reactor using a peristaltic pump. The reaction temperature was controlled at 10-20℃ and the reaction was carried out for 1.5h. After the reaction was completed, 188.5g of isothiourea propanesulfonic acid inner salt was obtained. S2. Neutralize the isothiourea propanesulfonic acid inner salt mentioned in step S1 with 250g of sodium hydroxide solution with a mass concentration of 30% at a reaction temperature of 30°C for 2 hours. After the reaction is completed, an aqueous solution of sodium 3-mercaptopropanesulfonate is obtained. After the reaction is completed, hydrogen peroxide with a volume concentration of 27.5% is added for oxidation to obtain crude sodium polydisulfide dipropanesulfonate solution. S3. The crude sodium disulfide dipropane sulfonate aqueous solution was filtered using a polyamide nanofiltration membrane with a molecular weight cutoff of 200-500 Da. The nanofiltration membrane pressure was 0.8 MPa and the temperature was 30°C. Impurities passed through the nanofiltration membrane, yielding a high-purity sodium disulfide dipropane sulfonate solution. After drying, 158.3 g of the finished sodium disulfide dipropane sulfonate product was obtained, with a yield of 89.44%. Figure 3 The purity is 99.34%.

[0034] Example 2

[0035] This embodiment proposes a method for preparing high-purity sodium polydisulfide dipropane sulfonate, comprising the following steps: S1. 116g (0.95mol) of 1,3-propanesulfonyl lactone and 1mol of thiourea aqueous solution (76g of thiourea and 500g of water were mixed evenly to obtain thiourea aqueous solution) were introduced into a tubular reactor using a peristaltic pump. The reaction temperature was controlled at 20-30℃ and the reaction was carried out for 1h. After the reaction was completed, 185.3g of isothiourea propanesulfonic acid inner salt was obtained. S2. The above-mentioned isothiourea propanesulfonic acid inner salt is neutralized with 160g of 30% sodium hydroxide solution at a reaction temperature of 25℃ for 2.5h. After the reaction is completed, an aqueous solution of sodium 3-mercaptopropanesulfonate is obtained. After the reaction is completed, air is blown to oxidize the solution to obtain crude sodium polydisulfide dipropanesulfonate solution.

[0036] S3. The crude sodium disulfide dipropane sulfonate aqueous solution was filtered using a polyamide nanofiltration membrane with a molecular weight cutoff of 200-500 Da. The nanofiltration membrane pressure was 1.0 MPa and the temperature was 25°C. Impurities passed through the nanofiltration membrane, resulting in a high-purity sodium disulfide dipropane sulfonate solution. After drying, 156.7 g of the finished sodium disulfide dipropane sulfonate product was obtained, with a yield of 93.19% and a purity of 99.58%.

[0037] Example 3

[0038] A method for preparing high-purity sodium polydisulfide dipropane sulfonate includes the following steps: S1. 119.5g (0.98mol) of 1,3-propanesulfonyl lactone and 1mol of thiourea aqueous solution (76g of thiourea and 500g of water were mixed evenly to obtain thiourea aqueous solution) were introduced into a tubular reactor using a peristaltic pump. The reaction temperature was controlled at 10-20℃ and the reaction was carried out for 1.5h. After the reaction was completed, 184.5g of isothiourea propanesulfonic acid inner salt was obtained.

[0039] S2. The above-mentioned isothiourea propanesulfonic acid inner salt is neutralized with 200g of 30% sodium hydroxide solution at a reaction temperature of 35℃ for 3h. After the reaction is completed, an aqueous solution of sodium 3-mercaptopropanesulfonate is obtained. After the reaction is completed, oxygen is blown in for oxidation to obtain crude sodium polydisulfide dipropanesulfonate solution.

[0040] S3. The crude sodium disulfide dipropane sulfonate aqueous solution was filtered using a polyamide nanofiltration membrane with a molecular weight cutoff of 200-500 Da. The nanofiltration membrane pressure was 0.5 MPa and the temperature was 35 °C. Impurities passed through the nanofiltration membrane, resulting in a high-purity sodium disulfide dipropane sulfonate solution. After drying, 156.6 g of the finished sodium disulfide dipropane sulfonate product was obtained, with a yield of 90.28% and a purity of 99.46%.

[0041] Comparative Example 1 The difference between the preparation method of this comparative example and that of Example 1 is that in step S1, thiourea is dissolved in methanol instead of water. Specifically, 76g of thiourea is mixed with 500g of methanol to obtain a thiourea methanol solution. Other steps and process conditions are the same as in Example 1. After drying, 103.5g of sodium polydisulfide dipropane sulfonate is obtained, with a yield of 58.47% and a purity of 99.26%.

[0042] Comparative Example 2 The difference between the preparation method of this comparative example and that of Example 1 is that, in step S1, the reaction is carried out in a four-necked flask instead of a tubular reactor. Specifically: S1. Add 76g of thiourea to a 1000ml four-necked flask equipped with a thermometer and a tetrafluoro mechanical stirrer, add 500g of deionized water and stir to dissolve, then add 122g of 1,3-propanesulfonyl lactone dropwise using a dropping funnel. The reaction temperature is controlled at 20-30℃. After the reaction is completed, 154.3g of isothiourea propanesulfonic acid inner salt is obtained. S2. The above-mentioned isothiourea propanesulfonic acid inner salt is neutralized with 250g of 30% sodium hydroxide solution at a reaction temperature of 30℃. After the reaction is completed, an aqueous solution of sodium 3-mercaptopropanesulfonate is obtained. After the reaction is completed, hydrogen peroxide with a volume concentration of 27.5% is added for oxidation to obtain crude sodium polydisulfide dipropanesulfonate solution. S3. The crude sodium disulfide dipropane sulfonate aqueous solution was filtered using a polyamide nanofiltration membrane with a molecular weight cutoff of 200-500 Da. The nanofiltration membrane pressure was 1.0 MPa and the temperature was 25°C. Impurities passed through the nanofiltration membrane, resulting in a high-purity sodium disulfide dipropane sulfonate solution. After drying, 103.5 g of the finished sodium disulfide dipropane sulfonate product was obtained, with a yield of 58.47% and a purity of 99.29%.

[0043] This invention employs a tubular reactor, which lowers the reaction temperature and avoids the continuous accumulation and hydrolysis of 1,3-propanesulfonyl lactone, thus improving the yield of the intermediate isothiourea propanesulfonic acid inner salt. Furthermore, the absence of organic solvents in the reaction significantly reduces environmental pollution and raw material costs. The reaction can be achieved at lower temperatures, resulting in low energy consumption, a short production cycle, and high production safety. Purification is performed using nanofiltration membranes, leveraging their high efficiency in retaining divalent ions to efficiently purify sodium polydithiopropanesulfonate, thereby improving purification efficiency, increasing product yield, and reducing production costs.

[0044] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing sodium polydisulfide dipropane sulfonate, characterized in that, Includes the following steps: S1. 1,3-Propanesulfonyl lactone and thiourea aqueous solution are mixed and reacted at 10-20℃ to obtain isothiourea propanesulfonic acid inner salt; S2. The isothiourea propanesulfonic acid inner salt is neutralized with sodium hydroxide aqueous solution at 25-35°C to obtain sodium 3-mercaptopropanesulfonate aqueous solution. Then, an oxidizing agent is added for oxidation to obtain crude sodium polydithiopropanesulfonate aqueous solution.

2. The method for preparing sodium polydisulfide dipropane sulfonate according to claim 1, characterized in that, Step S2 is followed by step S3: The crude sodium polydisulfide dipropane sulfonate aqueous solution obtained in step S2 was filtered through a nanofiltration membrane to obtain purified sodium polydisulfide dipropane sulfonate.

3. The method for preparing sodium polydisulfide dipropane sulfonate according to claim 1, characterized in that, In step S1, the molar ratio of 1,3-propanesulfonyl lactone to thiourea in the thiourea aqueous solution is (0.95-1):

1.

4. The method for preparing sodium polydisulfide dipropane sulfonate according to claim 1, characterized in that, In step S1, the 1,3-propanesulfonyl lactone and the thiourea aqueous solution are introduced into a tubular reactor for mixing and reaction.

5. The method for preparing sodium polydisulfide dipropane sulfonate according to claim 1, characterized in that, In step S2, the molar ratio of the isothiourea propanesulfonic acid inner salt to sodium hydroxide in the sodium hydroxide aqueous solution is 1:(1.2-2).

6. The method for preparing sodium polydisulfide dipropane sulfonate according to claim 1, characterized in that, In step S2, the oxidant is one or more of hydrogen peroxide, air, and oxygen.

7. The method for preparing sodium polydithiodipropane sulfonate according to claim 2, characterized in that, In step S3, the nanofiltration membrane is a nanomembrane made of aromatic polyamide with a molecular weight cutoff of 200-500 Da.

8. The method for preparing sodium polydithiodipropane sulfonate according to claim 2, characterized in that, In step S3, the filtration pressure of the nanofiltration membrane is 0.5-1.0 MPa and the temperature is 25-35℃.

9. A sodium polydisulfide dipropane sulfonate, characterized in that, It is prepared by the preparation method according to any one of claims 1-8.

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