Preparation method of sodium fatty alcohol sulfoacetate
The solvent-free synthesis method for sodium salts of fatty alcohol sulfoacetate solves the problems of product viscosity and agglomeration and ester hydrolysis caused by high-temperature reactions in existing technologies, and achieves a high-purity, low-energy preparation process suitable for high-end personal care and pharmaceutical products.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- GUANGZHOU FLOWERS SONG FINE CHEM CO LTD
- Filing Date
- 2026-01-15
- Publication Date
- 2026-05-12
AI Technical Summary
Existing methods for preparing sodium salts of fatty alcohol sulfoacetate involve high reaction temperatures, products that are prone to viscous agglomeration, poor mass transfer, and the use of phase transfer catalysts that lead to ester group hydrolysis. Furthermore, the reaction efficiency is low at high temperatures, resulting in low product purity and high energy consumption.
Sodium salts of fatty alcohol sulfoacetate were synthesized mechanically. The synthesis was carried out without solvents, using sodium sulfite and sodium bisulfite as sulfonating agents, combined with zirconium oxide or alumina ball milling media, and the reaction temperature was controlled below 150°C to avoid the use of phase transfer catalysts and improve mass transfer efficiency.
The reaction temperature was lowered, the conversion rate was increased, byproducts were reduced, production costs were lowered, and the product had good purity and stability, making it suitable for high-end personal care and pharmaceutical applications.
Smart Images
Figure CN122010793A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of chemical synthesis technology, specifically to a method for preparing sodium salt of fatty alcohol sulfonate. Background Technology
[0002] Sodium fatty alcohol sulfonate, as a mild anionic surfactant, is widely used in high-end personal care products such as shower gels, shampoos, facial cleansers, and bubble baths due to its excellent foaming properties, low irritation, and natural biodegradability. It is milder than K12 (sodium lauryl sulfate) and AES (sodium fatty alcohol polyoxyethylene ether sulfate) and can be used in infant and toddler washing products. Furthermore, sodium fatty alcohol sulfonate also has anti-inflammatory and antibacterial properties, thus it is also used as a pharmaceutical excipient in dental care products and laxatives. Currently, there are few reports on the synthesis of sodium fatty alcohol sulfonate, mainly focusing on two synthetic approaches: esterification followed by sulfonation and direct esterification. Chinese patent CN109293533A uses lauryl alcohol and acetic acid to esterify lauryl acetate, and then uses sodium methanesulfonate as a sulfonating agent to sulfonate sodium lauryl sulfoacetate. Chinese patent CN109796378A uses sodium sulfoacetate to directly esterify fatty alcohols to obtain sodium fatty alcohol sulfoacetate. Foreign reports indicate that bromoacetic acid and fatty alcohols are first esterified, and then sulfonated with excess sodium sulfite. Earlier methods also used chloroacetyl chloride and fatty alcohols for esterification followed by sulfonation. However, regardless of whether esterification is performed before sulfonation or directly, high-temperature heating is required during the reaction process due to the product's melting point being above 150℃. Furthermore, this substance has strong thickening properties in water, and a 20% aqueous solution is insoluble. Therefore, this product is generally sold as a powder, with a significant market presence in Europe, the United States, Canada, South Korea, Japan, Australia, and Southeast Asian countries. However, the domestic market for this product is still in the exploratory stage. Summary of the Invention
[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for preparing sodium salt of fatty alcohol sulfoacetate.
[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a method for preparing sodium salt of fatty alcohol sulfonyl acetate, comprising the following steps: (1) Add fatty alcohol and chloroacetic acid to a flask and heat to dissolve. Then add a catalyst, heat and keep the reaction at the temperature, and then cool down to obtain crude fatty alcohol chloroacetic acid ester. (2) Place the crude product of fatty alcohol chloroacetate in a separatory funnel and recover the catalyst in the lower layer. Wash the upper layer solution with water and separate the upper liquid to obtain fatty alcohol chloroacetate. (3) Add fatty alcohol chloroacetate to a ball mill jar, and add sulfonating agent and ball milling media for grinding to obtain sodium salt of fatty alcohol sulfoacetate.
[0005] Existing methods for preparing sodium salts of fatty alcohol sulfonates result in low purity, numerous byproducts, high reaction temperatures, and a gel-like consistency during the reaction that is difficult to stir, affecting mass transfer. The addition of large amounts of water leads to energy consumption issues during subsequent dehydration, and the discharge temperature is high, requiring temperatures above 150°C. Furthermore, since the esters are insoluble in water, a phase transfer catalyst is often needed to improve the reaction yield. Additionally, the pH of sodium sulfite aqueous solution is around 9, and with increasing temperature, unreacted esters inevitably hydrolyze into the corresponding fatty alcohols at high temperatures, reducing the conversion rate of the reaction. The method for preparing sodium sulfonate salt of fatty alcohols of the present invention addresses the problems of high sulfonation reaction temperature, viscous agglomeration during product reaction, poor mass transfer during reaction, the use of phase transfer catalysts, and the tendency of sodium sulfite aqueous solution to cause ester hydrolysis. It employs a mechanical, solvent-free synthesis method for sodium sulfonate salt of fatty alcohols, eliminating the need for additional phase transfer catalysts and solvents during the reaction. This solves the problem of stirring difficulties caused by thickening during the reaction, improves the mass transfer efficiency of the material, avoids the use of solvents, reduces the need for subsequent dehydration in powdering, reduces post-processing steps, and improves product purity while reducing costs and increasing efficiency.
[0006] In a preferred embodiment of the method for preparing sodium salt of fatty alcohol sulfonyl acetate according to the present invention, step (1) includes at least one of the following (a)-(f): (a) Fatty alcohols include single higher alcohols or a mixture of higher alcohols; (b) Fatty alcohols have 8-20 carbon atoms; (c) The molar ratio of fatty alcohol to chloroacetic acid is fatty alcohol:chloroacetic acid = 1:0.8-2.0; (d) The catalyst is an acidic catalyst; (e) The amount of catalyst used is 1.0-5.0% of the mass of the fatty alcohol; (f) The heating and heat preservation reaction is specifically heated to 100-150℃ and kept at that temperature until no water evaporates, and then the reaction continues for 0-3 hours.
[0007] More preferably, the amount of catalyst used is 3.4-4.0% of the mass of the fatty alcohol.
[0008] In a preferred embodiment of the method for preparing sodium salt of fatty alcohol sulfoacetate according to the present invention, the amount of water added in step (2) is 10-50% of the mass of fatty alcohol chloroacetate.
[0009] In a preferred embodiment of the method for preparing sodium salt of fatty alcohol sulfoacetate according to the present invention, the washing is performed 0-5 times in step (2).
[0010] More preferably, the number of times the washing is performed in step (2) is 1-2 times.
[0011] In a preferred embodiment of the method for preparing sodium salt of fatty alcohol sulfoacetate according to the present invention, step (3) includes at least one of the following (a)-(c): (a) The sulfonating agent includes at least one of concentrated sulfuric acid, chlorosulfonic acid, sulfur trioxide, sodium sulfite or sodium bisulfite; (b) The milling media include at least one of stainless steel, zirconium oxide, tungsten carbide or alumina; (c) The specific grinding parameters are: frequency 15-45Hz, temperature 30-80℃, and time 0-4h.
[0012] In a preferred embodiment of the method for preparing sodium salt of fatty alcohol sulfoacetate according to the present invention, the sulfonating agent in step (3) is a mixture of sodium sulfite and sodium bisulfite.
[0013] In a preferred embodiment of the preparation method of sodium sulfonate of fatty alcohols according to the present invention, the molar ratio of sodium sulfite and sodium bisulfite in the sulfonating agent is 5.66-19:1.
[0014] The inventors of this application have discovered that the type and content of the sulfonating agent significantly affect the product conversion rate of this method. Sodium bisulfite, after dissociation, has a pH of approximately 9. With increasing temperature, the ester inevitably hydrolyzes into the corresponding fatty alcohol at high temperatures, reducing the conversion rate. The addition of sodium bisulfite primarily lowers the system pH, maintaining it at around 7-9 to prevent hydrolysis and improve the conversion rate. Furthermore, sodium bisulfite acts as a strong reducing agent, preventing oxidation during the reaction and ensuring color while reducing potential side reactions. However, this reaction requires a pH greater than 7 for complete completion. Excessive sodium bisulfite will cause the system pH to decrease as the reaction proceeds, affecting subsequent reaction efficiency. Therefore, when a molar ratio of sodium sulfite to sodium bisulfite of 5.66-19:1 is selected as the sulfonating agent, the prepared sodium sulfoacetate of fatty alcohol exhibits a high conversion rate.
[0015] In a preferred embodiment of the method for preparing sodium salt of fatty alcohol sulfoacetate according to the present invention, the ball milling media is 6-10 mm zirconium oxide or alumina.
[0016] The inventors of this application have discovered that smaller grinding media can provide a larger surface area per unit volume, which is beneficial for improving the overall grinding reaction efficiency, but comes with more power and energy loss; while larger grinding media generally provide higher impact energy, which can significantly shorten grinding time. Stainless steel grinding media are more economical, capable of achieving large impact forces to provide sufficient energy for the reaction, but this is accompanied by some iron contamination, causing some metal parameters of the product to fail to meet industry standards. Ceramic balls such as zirconium oxide or alumina have good metallic inertness and wear resistance, although the impact energy they provide is not as high as that of steel balls. However, through extensive experimental research, it has been verified that the 6-10mm zirconium oxide or alumina grinding media selected in this method have better reaction efficiency and lower production costs.
[0017] In a preferred embodiment of the preparation method of sodium salt of fatty alcohol sulfoacetate according to the present invention, the specific parameters of the grinding are a frequency of 30-35Hz, a temperature of 40-60℃, and a time of 1-2h.
[0018] The present invention also provides the application of the preparation method of the sodium salt of fatty alcohol sulfoacetate in the production of anionic surfactants.
[0019] The beneficial effects of this invention are as follows: This invention provides a method for preparing sodium salt of fatty alcohol sulfonate. This invention mainly addresses the problems in the prior art of preparing sodium salt of fatty alcohol sulfonate, such as high sulfonation reaction temperature, viscous agglomeration during the reaction, poor mass transfer, the use of phase transfer catalysts, and the tendency of sodium sulfite aqueous solution to cause ester hydrolysis. This invention employs a mechanical method to synthesize sodium salt of fatty alcohol sulfonate. This method has a low reaction temperature, high conversion rate, no gelation phenomenon during the reaction process, no solvent or phase transfer catalyst in the reaction medium, fewer byproducts, avoids subsequent dehydration problems, reduces production costs, produces a light color, has little odor, good stability, and allows for better formulation design. Attached Figure Description
[0020] Figure 1 This is the high-performance liquid chromatogram of lauryl chloroacetate.
[0021] Figure 2 This is the high-performance liquid chromatogram of sodium lauryl sulfoacetate. Detailed Implementation
[0022] The following detailed embodiments further illustrate the above-described content of the present invention. However, this should not be construed as limiting the scope of the present invention to the following examples. All technologies implemented based on the above-described content of the present invention fall within the scope of the present invention. Unless otherwise specified, the reagents involved in the embodiments of the present invention are all commercially available products and can be purchased through commercial channels.
[0023] Example 1 This embodiment provides a method for preparing sodium lauryl sulfoacetate, comprising the following steps: (1) Weigh 96.5g of chloroacetic acid and 186.3g of lauryl alcohol into a flask with a distillation tube, stir and heat to 40°C. After all the chloroacetic acid in the flask is dissolved in the lauryl alcohol, add 5.6g of sulfuric acid and heat to 120°C. At this time, water will evaporate. Continue the reaction for 30 minutes until no more water evaporates. After turning off the heating and cooling to room temperature, crude lauryl chloroacetate product is obtained. (2) The crude lauryl chloroacetate product from step (1) was transferred to a separatory funnel and allowed to stand for 10 minutes. The lower layer of sulfuric acid solution was recovered, and the upper layer of liquid was washed with 55g of water. After standing for 10 minutes, the lower layer of aqueous solution was recovered, and the upper layer of solution was washed once more. The washed upper layer of product was poured out for later use. After testing, lauryl chloroacetate with a solid content of 98.8% was obtained. (3) Take 66g of lauryl chloroacetate from step (2) and place it in a 250ml polytetrafluoroethylene ball mill jar with 10mm zirconium oxide. Add 32.3g of sulfonating agent (the molar ratio of sodium sulfite to sodium bisulfite in the sulfonating agent is 9:1) at room temperature. After sealing, mechanically grind at a working frequency of 30Hz for 1h. The temperature of the ball mill should not exceed 60℃. After the reaction is completed, separate the zirconium beads and the product to obtain sodium lauryl sulfoacetate powder.
[0024] Example 2 This embodiment provides a method for preparing sodium stearyl sulfonate, comprising the following steps: (1) Weigh 270.5g of stearyl alcohol and put it into a flask with a distillation tube. Stir and heat to 60°C. After the stearyl alcohol in the flask is completely dissolved, add 111.5g of chloroacetic acid and stir to dissolve the chloroacetic acid. Add 10g of sulfuric acid and heat to 140°C. Water will evaporate at this time. Continue to react for 1 hour until no more water evaporates. Turn off the heating and cool to room temperature to obtain the crude product of stearyl alcohol chloroacetate. (2) Transfer the crude stearyl chloroacetate product from step (1) to a separatory funnel and let it stand for 10 minutes. Recover the lower layer of sulfuric acid solution, wash the upper layer of liquid with 80g of water, let it stand for 10 minutes, and then recover the lower layer of aqueous solution. Continue washing the upper layer of solution once more. Pour out the washed upper layer product for later use. After testing, stearyl chloroacetate with a solid content of 99.3% is obtained.
[0025] (3) Take 86.8g of stearyl chloroacetate from step (2) and place it in a 250ml polytetrafluoroethylene ball mill jar with 10mm zirconium oxide. Add 35.3g of sulfonating agent (sodium sulfite: sodium bisulfite = 19:1) at room temperature. After sealing, mechanically grind at a working frequency of 30Hz for 1.5h. The temperature of the ball mill should not exceed 60℃. After the reaction is completed, separate the zirconium beads and the product to obtain sodium stearyl sulfoacetate powder. Take a sample to test its purity and reaction conversion rate.
[0026] Example 3 This embodiment provides a method for preparing sodium fatty alcohol sulfonate, including the following steps: (1) Weigh 102.0g of chloroacetic acid and 192.0g of fatty alcohol (Mw=192) and put them into a flask with a distillation tube. Stir and heat to 40°C. After the chloroacetic acid in the flask is completely dissolved in the fatty alcohol, add 7.2g of sulfuric acid and heat to 130°C. At this time, water will evaporate. Continue to react for 30 minutes until no more water evaporates. Turn off the heating and cool to room temperature to obtain crude fatty alcohol chloroacetic acid ester. (2) Transfer the crude fatty alcohol chloroacetate product from step (1) to a separatory funnel and let it stand for 10 minutes. Recover the lower layer of sulfuric acid solution, wash the upper layer of liquid with 60g of water, let it stand for 10 minutes, and then recover the lower layer of aqueous solution. Continue washing the upper layer of solution once more. Pour out the washed upper layer product for later use. After testing, fatty alcohol chloroacetate with a solid content of 99.1% is obtained.
[0027] (3) Take 67.8g of fatty alcohol chloroacetate from step (2) and place it in a 250ml polytetrafluoroethylene ball mill jar with 8mm zirconium oxide. Add 34.4g of sulfonating agent (sodium sulfite: sodium bisulfite = 19:1) at room temperature. After sealing, mechanically grind at a working frequency of 30Hz for 1h. The ball mill temperature should not exceed 60℃. After the reaction is completed, separate the zirconium beads and the product to obtain sodium salt powder of fatty alcohol sulfoacetate. Take a sample to test its purity and reaction conversion rate.
[0028] Example 4 This embodiment provides a method for preparing sodium lauryl sulfoacetate, comprising the following steps: (1) Weigh 96.5g of chloroacetic acid and 186.3g of lauryl alcohol into a flask with a distillation tube, stir and heat to 40°C. After all the chloroacetic acid in the flask is dissolved in the lauryl alcohol, add 5.6g of sulfuric acid and heat to 120°C. At this time, water will evaporate. Continue the reaction for 30 minutes until no more water evaporates. After turning off the heating and cooling to room temperature, crude lauryl chloroacetate product is obtained. (2) Transfer the crude lauryl chloroacetate product from step (1) to a separatory funnel and let it stand for 10 minutes. Recover the lower layer of sulfuric acid solution, wash the upper layer of liquid with 55g of water, let it stand for 10 minutes, and then recover the lower layer of aqueous solution. Continue washing the upper layer of solution once more. Pour out the washed upper layer product for later use. After testing, lauryl chloroacetate with a solid content of 98.8% is obtained. (3) Take 66g of lauryl chloroacetate from step (2) and place it in a 250ml polytetrafluoroethylene ball mill jar with 10mm zirconium oxide. Add 32.4g of sulfonating agent (the molar ratio of sodium sulfite to sodium bisulfite in the sulfonating agent is 5.66:1) at room temperature. After sealing, mechanically grind at a working frequency of 30Hz for 1h. The temperature of the ball mill should not exceed 60℃. After the reaction is completed, separate the zirconium beads and the product to obtain sodium lauryl sulfoacetate powder.
[0029] Comparative Example 1 This comparative example provides a method for preparing sodium lauryl sulfoacetate, comprising the following steps: (1) Weigh 96.5g of chloroacetic acid and 186.3g of lauryl alcohol into a flask with a distillation tube, stir and heat to 40°C. After all the chloroacetic acid in the flask is dissolved in the lauryl alcohol, add 5.6g of sulfuric acid and heat to 120°C. At this time, water will evaporate. Continue the reaction for 30 minutes until no more water evaporates. After turning off the heating and cooling to room temperature, crude lauryl chloroacetate product is obtained. (2) Transfer the crude lauryl chloroacetate product from step (1) to a separatory funnel and let it stand for 10 minutes. Recover the lower layer of sulfuric acid solution, wash the upper layer of liquid with 55g of water, let it stand for 10 minutes, and then recover the lower layer of aqueous solution. Continue washing the upper layer of solution once more. Pour out the washed upper layer product for later use. After testing, lauryl chloroacetate with a solid content of 98.6% is obtained.
[0030] (3) Take 66g of lauryl chloroacetate from step (2) and place it in a flask with a reflux condenser. While stirring, add 161.1g of 20% aqueous sulfonating agent (the molar ratio of sodium sulfite to sodium bisulfite in the sulfonating agent is 9:1). Heat to 70℃ and keep under reflux for 6h. After the reaction is complete, dry the water at 120℃ and collect sodium lauryl sulfoacetate.
[0031] Comparative Example 2 This comparative example provides a method for preparing sodium lauryl sulfoacetate, comprising the following steps: (1) Weigh 96.5g of chloroacetic acid and 186.3g of lauryl alcohol into a flask with a distillation tube, stir and heat to 40°C. After all the chloroacetic acid in the flask is dissolved in the lauryl alcohol, add 5.6g of sulfuric acid and heat to 120°C. At this time, water will evaporate. Continue the reaction for 30 minutes until no more water evaporates. After turning off the heating and cooling to room temperature, crude lauryl chloroacetate product is obtained. (2) Transfer the crude lauryl chloroacetate product from step (1) to a separatory funnel and let it stand for 10 minutes. Recover the lower layer of sulfuric acid solution, wash the upper layer of liquid with 80g of water, let it stand for 10 minutes, and then recover the lower layer of aqueous solution. Continue washing the upper layer of solution once more. Pour out the washed upper layer product for later use. After testing, lauryl chloroacetate with a solid content of 98.8% is obtained.
[0032] (3) Take 65.8g of lauryl chloroacetate from step (2) and place it in a 250ml polytetrafluoroethylene ball mill jar with 10mm zirconium oxide. Add 32.7g of sodium sulfite at room temperature. After sealing, mechanically grind at a working frequency of 30Hz for 1h. The temperature of the ball mill should not exceed 60℃. After the reaction is completed, separate the zirconium beads and the product to obtain sodium lauryl sulfoacetate.
[0033] Comparative Example 3 This comparative example provides a method for preparing sodium lauryl sulfoacetate, comprising the following steps: (1) Weigh 96.5g of chloroacetic acid and 186.3g of lauryl alcohol into a flask with a distillation tube, stir and heat to 40°C. After all the chloroacetic acid in the flask is dissolved in the lauryl alcohol, add 5.6g of sulfuric acid and heat to 120°C. At this time, water will evaporate. Continue the reaction for 30 minutes until no more water evaporates. After turning off the heating and cooling to room temperature, crude lauryl chloroacetate product is obtained. (2) Transfer the crude lauryl chloroacetate product from step (1) to a separatory funnel and let it stand for 10 minutes. Recover the lower layer of sulfuric acid solution, wash the upper layer of liquid with 80g of water, let it stand for 10 minutes, and then recover the lower layer of aqueous solution. Continue washing the upper layer of solution once more. Pour out the washed upper layer product for later use. After testing, lauryl chloroacetate with a solid content of 98.6% is obtained.
[0034] (3) Take 66.0g of lauryl chloroacetate from step (2) and place it in a 250ml polytetrafluoroethylene ball mill jar with 10mm zirconium oxide. Add 27.0g of sodium bisulfite at room temperature. After sealing, mechanically grind at a working frequency of 30Hz for 1.5h. The temperature of the ball mill should not exceed 60℃. After the reaction is completed, separate the zirconium beads and the product to obtain sodium lauryl sulfoacetate.
[0035] Comparative Example 4 This comparative example provides a method for preparing sodium lauryl sulfoacetate, comprising the following steps: (1) Weigh 96.5g of chloroacetic acid and 186.3g of lauryl alcohol into a flask with a distillation tube, stir and heat to 40°C. After all the chloroacetic acid in the flask is dissolved in the lauryl alcohol, add 5.6g of sulfuric acid and heat to 120°C. At this time, water will evaporate. Continue the reaction for 30 minutes until no more water evaporates. After turning off the heating and cooling to room temperature, crude lauryl chloroacetate product is obtained. (2) Transfer the crude lauryl chloroacetate product from step (1) to a separatory funnel and let it stand for 10 minutes. Recover the lower layer of sulfuric acid solution, wash the upper layer of liquid with 80g of water, let it stand for 10 minutes, and then recover the lower layer of aqueous solution. Continue washing the upper layer of solution once more. Pour out the washed upper layer product for later use. After testing, lauryl chloroacetate with a solid content of 98.6% is obtained.
[0036] (3) Take 66.0g of lauryl chloroacetate from step (2) and place it in a 250ml polytetrafluoroethylene ball mill jar with 10mm zirconium oxide. Add 30.0g of sulfonating agent (the molar ratio of sodium sulfite to sodium bisulfite in the sulfonating agent is 1:1) at room temperature. After sealing, mechanically grind at a working frequency of 30Hz for 1.5h. The temperature of the ball mill should not exceed 60℃. After the reaction is completed, separate the zirconium beads and the product to obtain sodium lauryl sulfoacetate. Take a sample to test its purity and reaction conversion rate.
[0037] Comparative Example 5 This comparative example provides a method for preparing sodium lauryl sulfoacetate, comprising the following steps: (1) Weigh 96.5g of chloroacetic acid and 186.3g of lauryl alcohol into a flask with a distillation tube, stir and heat to 40°C. After all the chloroacetic acid in the flask is dissolved in the lauryl alcohol, add 5.6g of sulfuric acid and heat to 120°C. At this time, water will evaporate. Continue the reaction for 30 minutes until no more water evaporates. After turning off the heating and cooling to room temperature, crude lauryl chloroacetate product is obtained. (2) Transfer the crude lauryl chloroacetate product from step (1) to a separatory funnel and let it stand for 10 minutes. Recover the lower layer of sulfuric acid solution, wash the upper layer of liquid with 80g of water, let it stand for 10 minutes, and then recover the lower layer of aqueous solution. Continue washing the upper layer of solution once more. Pour out the washed upper layer product for later use. After testing, lauryl chloroacetate with a solid content of 98.8% is obtained.
[0038] (3) Take 65.8g of lauryl chloroacetate from step (2) and place it in a 250ml polytetrafluoroethylene ball mill jar with 10mm zirconium oxide. Add 33.2g of sodium sulfite (sodium sulfite: sodium bisulfite = 20:1) at room temperature. After sealing, mechanically grind at a working frequency of 30Hz for 1h. The temperature of the ball mill should not exceed 60℃. After the reaction is completed, separate the zirconium beads and the product to obtain sodium lauryl sulfoacetate.
[0039] Comparative Example 6 This comparative example provides a method for preparing sodium lauryl sulfoacetate, comprising the following steps: (1) Weigh 96.5g of chloroacetic acid and 186.3g of lauryl alcohol into a flask with a distillation tube, stir and heat to 40°C. After all the chloroacetic acid in the flask is dissolved in the lauryl alcohol, add 5.6g of sulfuric acid and heat to 120°C. At this time, water will evaporate. Continue the reaction for 30 minutes until no more water evaporates. After turning off the heating and cooling to room temperature, crude lauryl chloroacetate product is obtained. (2) Transfer the crude lauryl chloroacetate product from step (1) to a separatory funnel and let it stand for 10 minutes. Recover the lower layer of sulfuric acid solution, wash the upper layer of liquid with 60g of water, let it stand for 10 minutes, and then recover the lower layer of aqueous solution. Continue washing the upper layer of solution once more. Pour out the washed upper layer product for later use. After testing, lauryl chloroacetate with a solid content of 98.7% is obtained.
[0040] (3) Take 66g of lauryl chloroacetate from step (2) and place it in a flask with a reflux condenser. While stirring, add 166.2g of 20% sodium sulfite aqueous solution and 15g of 95% ethanol. Heat to 100℃ and keep under reflux for 5h. After the reaction is complete, dry the water at 140℃ and collect the sodium lauryl sulfoacetate.
[0041] Example of effect 1. The sodium lauryl sulfoacetate powder prepared in Example 1 was analyzed by high performance liquid chromatography, and the results are as follows: Figure 1-2 As shown, Figure 1 The chromatograms are of the intermediate lauryl chloroacetate and the blank control. Figure 2 Chromatograms of lauryl sulfoacetate and blank control.
[0042] 2. The solid content, anionic activity, pH, sulfite content, and sodium chloride content of the sodium fatty alcohol sulfoacetate powders prepared in Examples 1-3 and Comparative Examples 1-4 were tested, and their conversion rates were calculated according to the formula. The testing methods are as follows: Powder solid content: The test standard refers to "GB / T 13173-2021 Test Methods for Surfactants and Detergents"; Anionic active ingredient content: The test standard refers to GB / T 5173-2018; pH: The test standard refers to "GB / T 6368-2008 Determination of pH of Aqueous Solutions of Surfactants by Potentiometric Method"; Sulfite content: 《GB 1886.8-2015 National Food Safety Standard for Food Additives - Sodium Sulfite》; Sodium chloride content: 《GB / T 15963-2022 Sodium dodecyl sulfate》; Conversion rate calculation formula: The results are shown in Table 1.
[0043] Table 1 Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.
Claims
1. A method for preparing a sodium salt of fatty alcohol sulfonyl acetate, characterized in that, Includes the following steps: (1) Add fatty alcohol and chloroacetic acid to a flask and heat to dissolve. Then add a catalyst, heat and keep the reaction at the temperature, and then cool down to obtain crude fatty alcohol chloroacetic acid ester. (2) Place the crude product of fatty alcohol chloroacetate in a separatory funnel and recover the catalyst in the lower layer. Wash the upper layer solution with water and separate the upper liquid to obtain fatty alcohol chloroacetate. (3) Add fatty alcohol chloroacetate to a ball mill jar, and add sulfonating agent and ball milling media for grinding to obtain sodium salt of fatty alcohol sulfoacetate.
2. The method for preparing sodium salt of fatty alcohol sulfonyl acetate according to claim 1, characterized in that, Step (1) includes at least one of the following (a)-(f): (a) Fatty alcohols include single higher alcohols or a mixture of higher alcohols; (b) Fatty alcohols have 8-20 carbon atoms; (c) The molar ratio of fatty alcohol to chloroacetic acid is fatty alcohol:chloroacetic acid = 1:0.8-2.0; (d) The catalyst is an acidic catalyst; (e) The amount of catalyst used is 1.0-5.0% of the mass of the fatty alcohol; (f) The heating and heat preservation reaction is specifically heated to 100-150℃ and kept at that temperature until no water evaporates, and then the reaction continues for 0-3 hours.
3. The method for preparing sodium salt of fatty alcohol sulfonyl acetate according to claim 1, characterized in that, In step (2), the amount of water added is 10-50% of the mass of fatty alcohol chloroacetate.
4. The method for preparing sodium salt of fatty alcohol sulfonate according to claim 1, characterized in that, The number of times the washing is performed in step (2) is 0-5 times.
5. The method for preparing sodium salt of fatty alcohol sulfonyl acetate according to claim 1, characterized in that, Step (3) includes at least one of the following (a)-(c): (a) The sulfonating agent includes at least one of concentrated sulfuric acid, chlorosulfonic acid, sulfur trioxide, sodium sulfite or sodium bisulfite; (b) The milling media include at least one of stainless steel, zirconium oxide, tungsten carbide or alumina; (c) The specific grinding parameters are: frequency 15-45Hz, temperature 30-80℃, and time 0-4h.
6. The method for preparing sodium salt of fatty alcohol sulfonyl acetate according to claim 5, characterized in that, The sulfonating agent in step (3) is a mixture of sodium sulfite and sodium bisulfite.
7. The method for preparing sodium salt of fatty alcohol sulfonyl acetate according to claim 6, characterized in that, The molar ratio of sodium sulfite to sodium bisulfite in the sulfonating agent is 5.66-19:
1.
8. The method for preparing sodium salt of fatty alcohol sulfonate according to claim 5, characterized in that, The ball milling media are 6-10 mm zirconium oxide or alumina.
9. The method for preparing sodium salt of fatty alcohol sulfonate according to claim 5, characterized in that, The specific grinding parameters are: frequency of 30-35Hz, temperature of 40-60℃, and time of 1-2h.
10. The application of the method for preparing sodium salt of fatty alcohol sulfoacetate according to any one of claims 1-9 in the production of anionic surfactants.