Process for preparing fatty alcohol ether sulfonate by reacting allyl-terminated fatty alcohol polyoxyethylene ether with SO3

Abstract

The present invention discloses a process for preparing fatty alcohol ether sulfonate by reacting allyl-terminated fatty alcohol polyoxyethylene ether with SO3. The process comprises the following steps: a SO3 / dry air mixed gas is filtered and then enters the top of a membrane sulfonator, while the allyl-terminated fatty alcohol polyoxyethylene ether also enters from the top of the sulfonator. Circulating water is passed through the jacket of the sulfonator to remove the reaction heat, and the sulfonation product exits from the bottom of the sulfonator, completing the sulfonation reaction. The sulfonation product is a mixture of sulfonic acid and sultone. The sulfonation product is then neutralized with an alkaline solution, and the sulfonic acid reacts with the base to form the corresponding sulfonate. Finally, the process is hydrolyzed, and the sultone reacts with the base to obtain the fatty alcohol ether sulfonate. The raw materials of the present invention are readily available, the preparation process is simple, the conversion rate is high, the obtained product does not require purification, and the existing large-scale sulfonation equipment can be used for industrial production, which is safe and environmentally friendly.

Description

Technical Field

[0001] The invention relates to a process for preparing anionic surfactant fatty alcohol ether sulfonate by reacting allyl-terminated fatty alcohol polyoxyethylene ether with sulfur trioxide gas, and belongs to the field of anionic surfactant preparation. Background Art

[0002] Surfactants, often called the "MSG of industry," are widely used in consumer cleaning, personal care, mineral flotation, industrial cleaning, and oilfield extraction. High-temperature, high-mineralization environments, such as oil extraction and industrial cleaning, place even more stringent requirements on surfactants. Traditional anionic surfactants, such as alkylbenzene sulfonates (LAS) and α-olefin sulfonates (AOS), have good temperature resistance but poor hard water resistance. Fatty alcohol polyoxyethylene ether sulfates (AES), one of the most widely used anionic surfactants in the daily chemical industry, have good hard water resistance, but the sulfate ester bond in the molecule is unstable at high temperatures and easily decomposes, limiting their use in high-temperature environments. Therefore, the development of anionic surfactants that are both salt-tolerant and heat-resistant is of great significance.

[0003] Fatty alcohol ether sulfonates are a class of anionic-nonionic surfactants containing both EO and sulfonic acid groups within their molecules. They combine the temperature resistance of anionic surfactants with the salt tolerance of nonionic surfactants, offering promising applications in extreme environments such as high temperatures (>100°C) and high salt concentrations (NaCl concentrations >200g / L). The molecular structure of these surfactants is highly controllable, allowing them to be tailored to meet the needs of diverse environments.

[0004] The main methods for synthesizing fatty alcohol ether sulfonates include sulfate group conversion, sulfoalkylation, olefin addition, and sulfite sulfonation. U.S. Patent No. 4226807 proposes using alkyl alcohol polyoxyethylene ethers as raw materials, KOH as a catalyst, and reacting them with sodium isethionate at 180-190°C in a vacuum environment to produce the alkyl alcohol ether sulfonates. During the reaction, inert gases such as N2 are introduced to remove the byproduct water, which produces foaming. The conversion rate is only 70-80%, and the reaction is difficult to control. Li Ruidong (Study on Sulfonation Conditions in the Synthesis of Alkylphenol Polyoxyethylene Ether Sulfonates by the Streck Method. Journal of Xi'an Shiyou University (Natural Science Edition), 2010) used octylphenol polyoxyethylene ethers as raw materials, first reacting them with thionyl chloride to obtain an intermediate. Octylphenol polyoxyethylene ether sulfonates were then synthesized using sodium sulfite, a mixture of sodium sulfite and sodium bisulfite, and potassium sulfite as sulfonating agents, respectively. The final yield was only 82.6%. The synthesis process produces acidic waste gases, HCl and SO₂, which pollute the environment and are corrosive to equipment, making industrial production difficult. A Chinese patent (publication number CN101979426A) uses fatty alcohol (alkylphenol) polyoxyethylene ether as the raw material. Allylation is performed to obtain an allyl-terminated fatty alcohol polyoxyethylene ether intermediate. Sodium sulfite and sodium bisulfite (1:2) are used as sulfonating agents, resulting in a final product yield of 90.7%. A large amount of inorganic salts remain after the reaction, requiring removal with an organic solvent.

[0005] Chinese patent CN112680208A discloses a "process for preparing oleyl alcohol ether sulfonate / sulfate." The raw material molecule contains a terminal alcohol hydroxyl group and an internal olefin double bond, corresponding to a sulfation reaction and a sulfonation reaction, respectively. The sulfonation of the double bond is the sulfonation of the internal olefin double bond. The sulfonation intermediate is mainly β-sultone. In addition, the domestic resources of oleyl alcohol, the raw material of oleyl alcohol polyoxyethylene ether, are relatively scarce and basically rely on imports, resulting in a high price.

[0006] In view of the shortcomings of the above technologies, the present invention provides a new preparation process of fatty alcohol ether sulfonate. Summary of the Invention

[0007] The present invention provides a process for preparing fatty alcohol ether sulfonates by reacting allyl-terminated fatty alcohol polyoxyethylene ethers with SO₃. The fatty alcohol ether sulfonates prepared by the present invention contain both EO and sulfonic acid groups in their molecules and exhibit heat and salt resistance. The SO₃ membrane sulfonation process employed in the present invention is the most economical and efficient means of introducing sulfonic acid groups into molecules.

[0008] The present invention uses SO₃ as a sulfonating agent to react with allyl-terminated fatty alcohol polyoxyethylene ethers to prepare fatty alcohol ether sulfonates. This process exhibits few side reactions and is a typical "atom-economic reaction." Furthermore, the process is continuous and can be produced using existing industrial sulfonation equipment. The product is high in purity, requiring no purification, resulting in high production efficiency and low cost. Compared to the prior patent application CN112680208A, the present invention utilizes allyl-terminated fatty alcohol polyoxyethylene ethers as the raw material, with the terminal double bonds reacting. The two differ in terms of reaction: the previous technical solution involved both sulfonation and sulfation, with the double bond sulfonation being internal olefin sulfonation, while the present application sulfonates terminal olefins. The sulfonation intermediate is initially a β-sultone, which then rearranges to form a γ-sultone and an olefin sulfonic acid. The reaction mechanisms involved in the two methods are completely different. The raw material for the oleyl alcohol polyoxyethylene ethers in the prior patent application was imported, while the raw material in the present invention is more widely available and less expensive.

[0009] The present invention provides a preparation process of fatty alcohol ether sulfonate, which comprises the following steps:

[0010] The SO3 / dry air mixed gas enters the top of the membrane sulfonator after filtration. At the same time, allyl-terminated fatty alcohol polyoxyethylene ether also enters from the top of the sulfonator. Circulating water is passed through the jacket of the sulfonator to remove the reaction heat. The sulfonation product (a mixture of sulfonic acid and sultone) leaves from the bottom of the sulfonator, completing the sulfonation reaction. The sulfonation product is then neutralized with an alkaline solution. The sulfonic acid reacts with the base to form the corresponding sulfonate, which is finally hydrolyzed (the sultone reacts with the base) to obtain fatty alcohol ether sulfonate.

[0011] The structural formula of the allyl-terminated fatty alcohol polyoxyethylene ether as described above is as follows:

[0012]

[0013] Where R refers to an alkyl group, and the carbon chain is C8 to C 18 One or any mixture of several; n=1~10.

[0014] In the present invention, allyl-terminated fatty alcohol polyoxyethylene ether reacts with SO3 to generate β-sultone, which is rapidly rearranged into olefin sulfonic acid and γ-sultone, i.e., the sulfonated product leaving the sulfonator is a mixture of sulfonic acid and sultone. The product is then neutralized with a base, and the olefin sulfonic acid reacts with the base to generate the corresponding salt. Finally, the product is hydrolyzed, and the sultone reacts with the base to generate the corresponding sulfonate, thereby obtaining the target product, fatty alcohol ether sulfonate. The reaction mechanism is shown in the attached figure. Figure 3 shown.

[0015] The product fatty alcohol ether sulfonate in the above preparation process is a mixture of the following substances:

[0016]

[0017] In the formula, R refers to an alkyl group, and the carbon chain is C8 to C 18 One or any mixture of; M is an alkali metal, including one of sodium, potassium and lithium.

[0018] In the above preparation process, the process conditions are: in the SO3 / dry air mixed gas, the volume ratio of SO3 to air is 2.5~4.0:100, the molar ratio of SO3 to allyl-terminated fatty alcohol polyoxyethylene ether is 1.00~1.10:1, the jacket water temperature of the sulfonator is 20℃~70℃, the hydrolysis temperature is 90℃~150℃, and the hydrolysis time is 30min~240min.

[0019] In the SO3 / dry air mixed gas described above, SO3 is prepared by sulfur combustion or liquid SO3 evaporation.

[0020] The alkali mentioned above is one of sodium hydroxide, potassium hydroxide and lithium hydroxide.

[0021] Beneficial effects of the present invention:

[0022] (1) The raw materials of the present invention are easily available, the preparation process is simple, the conversion rate is high, the obtained product does not need to be purified, and the existing large-scale sulfonation equipment can be used for industrial production, which is safe and environmentally friendly.

[0023] (2) The obtained sulfonate product can be used in combination with traditional anionic surfactants alkylbenzene sulfonate and α-olefin sulfonate to improve the salt tolerance of the alkylbenzene sulfonate and α-olefin sulfonate compound system;

[0024] (3) The obtained fatty alcohol ether sulfonate can be combined with a cationic surfactant to reduce the oil / water interfacial tension to an ultra-low level (<0.01 mN / m). BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is the infrared spectrum of the raw material allyl-terminated fatty alcohol polyoxyethyl ether;

[0026] Figure 2 This is the infrared spectrum of the fatty alcohol ether sulfonate product obtained in Example 2;

[0027] Figure 3 This is the mechanism diagram for the preparation of fatty alcohol ether sulfonates by the reaction of allyl-terminated fatty alcohol polyoxyethylene ether with SO3. Implementation Method

[0028] The present invention is further illustrated below by way of examples, but is not limited to the following examples.

[0029] Example 1:

[0030] Allyl-terminated isooctyl alcohol polyoxyethylene ether (n = 1) was reacted with a SO₃ / dry air mixture obtained by a sulfur combustion method. The SO₃ / air volume ratio was 4.0%, and the molar ratio of SO₃ to allyl-terminated isooctyl alcohol polyoxyethylene ether was 1.00:1. The jacket water temperature of the sulfonator was maintained at 20°C. The sulfonated product was neutralized with lithium hydroxide solution and hydrolyzed at 110°C for 90 minutes to produce an aqueous solution of lithium fatty alcohol ether sulfonate. The product contained 3.1% unreacted matter (based on 100% total solids) and 0.8% lithium sulfate (based on 100% total solids).

[0031] Performance testing: A 0.5% concentration of the fatty alcohol ether sulfonate was clarified in a 200 g / L NaCl solution and a 1 g / L CaCl2 solution. The product showed no decomposition when heated at 150°C for 72 hours. The prepared fatty alcohol ether sulfonate, when mixed with dodecyltrimethylammonium chloride in a 6:4 ratio (mass ratio, total mass concentration 0.2%), exhibited ultra-low interfacial tension (<0.01 mN / m) with kerosene. Interfacial tension testing conditions: a temperature of 50°C, with a surfactant solution prepared in deionized water.

[0032] Example 2:

[0033] Allyl-terminated natural 12-14 alcohol polyoxyethylene ethers (n = 7) (12 alcohol / 14 alcohol mass ratio: 75 / 25) were reacted with a SO₃ / dry air mixture obtained by liquid SO₃ evaporation. The SO₃ / air volume ratio was 3.0%, and the molar ratio of SO₃ to allyl-terminated natural 12-14 alcohol polyoxyethylene ethers was 1.08:1. The jacket water temperature of the sulfonator was maintained at 40°C. The sulfonated product was neutralized with potassium hydroxide solution and hydrolyzed at 150°C for 30 minutes to produce an aqueous solution of potassium fatty alcohol ether sulfonate. The product contained 3.6% unreacted fatty alcohol ether sulfonate (based on 100% total solids) and 1.0% sodium sulfate (based on 100% total solids).

[0034] The infrared spectra of the raw material allyl-terminated fatty alcohol polyoxyethylene ether and the product fatty alcohol ether sulfonate are as follows: Figure 1 、 2 shown. Figure 2 At 3480cm -1 The characteristic absorption peaks of hydroxyl groups appeared at 1044 and 1226 cm -1 Two new absorption peaks appeared at , which were consistent with the characteristic absorption peak of -SO3Na, indicating the successful preparation of the product.

[0035] Performance test: 0.5% of the fatty alcohol ether sulfonate can be clarified in 200g / L NaCl solution and 10g / L CaCl2 solution, which can meet the needs of most applications. 14-16Sodium α-olefin sulfonate was mixed with 180 g / L NaCl solution at a mass ratio of 5 / 5 (total mass concentration of 0.5%) to clarify the solution, which improved the C 14-16 Salt tolerance of sodium α-olefin sulfonate (0.5% C 14-16 Sodium α-olefin sulfonate is turbid in a 70 g / L NaCl solution. This product showed no decomposition when heated at 150°C for 72 hours. The prepared fatty alcohol ether sulfonate, when mixed with didecyldimethylammonium chloride in a 4 / 6 ratio (mass ratio, total mass concentration 0.2%), exhibited ultra-low interfacial tension (<0.01 mN / m) with kerosene. Interfacial tension testing conditions were: a surfactant solution prepared at 50°C in a 50 g / L NaCl solution.

[0036] Example 3:

[0037] Allyl-terminated 16-18 alcohol polyoxyethylene ether (16 alcohol / 18 alcohol mass ratio: 60 / 40) (n = 5) was reacted with a SO₃ / dry air mixture obtained by liquid SO₃ evaporation. The SO₃ / air volume ratio was 2.5%, and the molar ratio of SO₃ to allyl-terminated 16-18 alcohol polyoxyethylene ether was 1.10:1. The jacket water temperature of the sulfonator was maintained at 70°C. The sulfonated product was neutralized with sodium hydroxide solution and hydrolyzed at 90°C for 240 minutes to produce an aqueous solution of sodium fatty alcohol ether sulfonate. The product contained 6.0% unreacted fatty alcohol ether (based on 100% total solids) and 1.5% sodium sulfate (based on 100% total solids).

[0038] Performance testing: 1.0% of the fatty alcohol ether sulfonate was clarified in a 200 g / L NaCl solution and a 10 g / L CaCl2 solution. The product showed no decomposition when heated at 150°C for 72 hours. The interfacial tension between the prepared fatty alcohol ether sulfonate and lauryl betaine, compounded at a 7:3 mass ratio (total mass concentration of 0.2%), and kerosene was 0.05 mN / m. The interfacial tension test conditions were: a temperature of 50°C, and a surfactant solution prepared in deionized water.

[0039] Example 4:

[0040] Allyl-terminated 1-decyl alcohol polyoxyethylene ether (n = 10) was reacted with a SO₃ / dry air mixture obtained by a sulfur combustion method. The SO₃ / air volume ratio was 3.5%, and the molar ratio of SO₃ to allyl-terminated 1-decyl alcohol polyoxyethylene ether was 1.10:1. The jacket water temperature of the sulfonator was maintained at 50°C. The sulfonated product was neutralized with sodium hydroxide solution and hydrolyzed at 130°C for 60 minutes to produce an aqueous solution of sodium fatty alcohol ether sulfonate. The product contained 7.5% unreacted fatty alcohol ether (based on 100% total solids) and 1.4% sodium sulfate (based on 100% total solids).

[0041] Performance testing: 0.5% of the fatty alcohol ether sulfonate was clarified in a 200 g / L NaCl solution and a 10 g / L CaCl2 solution. The product showed no decomposition when heated at 150°C for 72 hours. The prepared fatty alcohol ether sulfonate, when compounded with dioctyldimethylammonium chloride in a 6:4 ratio (mass ratio, total mass concentration of 0.2%), exhibited ultra-low interfacial tension (<0.01 mN / m) with kerosene. Interfacial tension testing conditions: 50°C, 100 g / L NaCl solution in a surfactant solution.

[0042] Example 5:

[0043] Allyl-terminated tridecanol polyoxyethylene ether (n = 6) was reacted with a SO₃ / dry air mixture obtained by a sulfur combustion method. The SO₃ / air volume ratio was 4.0%, and the molar ratio of SO₃ to allyl-terminated tridecanol polyoxyethylene ether was 1.05:1. The jacket water temperature of the sulfonator was maintained at 50°C. The sulfonated product was neutralized with sodium hydroxide solution and hydrolyzed at 120°C for 100 minutes to produce an aqueous solution of sodium fatty alcohol ether sulfonate. The product contained 5.5% unreacted fatty alcohol ether (based on 100% total solids) and 0.7% sodium sulfate (based on 100% total solids).

[0044] Performance testing: 0.5% of the fatty alcohol ether sulfonate was clarified in a 200 g / L NaCl solution and a 10 g / L CaCl2 solution. The product showed no decomposition when heated at 150°C for 72 hours. The prepared fatty alcohol ether sulfonate, hexadecyl betaine, and lauryl alcohol polyoxyethylene ether (EO=9) in a 4 / 2 / 4 mass ratio (total mass concentration of 0.2%) blend achieved ultra-low interfacial tension (<0.01 mN / m) with kerosene. Interfacial tension testing conditions: 50°C, 50 g / L NaCl solution in a surfactant solution.

[0045] Example 6:

[0046] Allyl-terminated octanol polyoxyethylene ether (n = 5) was reacted with a SO₃ / dry air mixture obtained by a sulfur combustion method. The SO₃ / air volume ratio was 3.0%, and the molar ratio of SO₃ to allyl-terminated octanol polyoxyethylene ether was 1.08:1. The jacket water temperature of the sulfonator was maintained at 30°C. The sulfonated product was neutralized with potassium hydroxide solution and hydrolyzed at 90°C for 180 minutes to produce an aqueous solution of potassium alcohol ether sulfonate. The product contained 4.0% unreacted solids (based on 100% total solids) and 0.8% sodium sulfate (based on 100% total solids).

[0047] Performance testing: 0.5% of this fatty alcohol ether sulfonate clarified in a 200g / L NaCl solution and a 10g / L CaCl2 solution. A 4 / 6 (mass ratio) mixture of this fatty alcohol ether sulfonate and sodium dodecylbenzenesulfonate clarified in a 100g / L NaCl solution, improving the salt tolerance of the sodium dodecylbenzenesulfonate. However, the sodium dodecylbenzenesulfonate became turbid in a 15g / L NaCl solution. The product showed no decomposition when heated at 150°C for 72 hours.

Claims

1. A process for preparing fatty alcohol ether sulfonate for oil field exploitation, characterized in that: The obtained fatty alcohol ether sulfonate is mixed with a cationic surfactant, and the oil / water interfacial tension is less than 0.01 mN / m; The preparation process steps of fatty alcohol ether sulfonate are as follows: The SO3 / dry air mixed gas is filtered and enters the top of the membrane sulfonator. At the same time, allyl-terminated fatty alcohol polyoxyethylene ether also enters from the top of the sulfonator. Circulating water is passed through the jacket of the sulfonator to remove the heat of reaction. The sulfonation product leaves the bottom of the sulfonator, completing the sulfonation reaction. The sulfonation product is a mixture of sulfonic acid and sultone. Then, the sulfonated product is neutralized with an alkaline solution, and the sulfonic acid reacts with the base to form the corresponding sulfonate, which is then hydrolyzed at a temperature of 90°C to 150°C for 30 minutes to 240 minutes. At this time, the sultone reacts with the base to obtain a fatty alcohol ether sulfonate. The structural formula of the allyl-terminated fatty alcohol polyoxyethylene ether is as follows: ； Where R refers to an alkyl group, and the carbon chain is C8 to C 18 One or any mixture of several; n=1~10; The resulting product, fatty alcohol ether sulfonate, is a mixture of the following substances: ； In the formula, R refers to an alkyl group, and the carbon chain is C8 to C 18 One or any mixture of; M is an alkali metal, including one of sodium, potassium and lithium.

2. The process for preparing the fatty alcohol ether sulfonate for oil field production according to claim 1, wherein: In the SO3 / dry air mixed gas, the volume ratio of SO3 to air is 2.5-4.0:100, and the molar ratio of SO3 to allyl-terminated fatty alcohol polyoxyethylene ether is 1.00-1.10:

1.

3. The process for preparing the fatty alcohol ether sulfonate for oil field production according to claim 1, wherein: The jacket water temperature of the sulfonator is 20℃~70℃.

4. The process for preparing the fatty alcohol ether sulfonate for oil field production according to claim 1, wherein: In the SO3 / dry air mixed gas, SO3 is prepared by sulfur combustion or liquid SO3 evaporation.

5. The process for preparing the fatty alcohol ether sulfonate for oil field production according to claim 1, wherein: The alkali is one of sodium hydroxide, potassium hydroxide and lithium hydroxide.

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