阅读说明：本技术 一种三氟甲磺酸的制备方法 (Preparation method of trifluoromethanesulfonic acid ) 是由 姚刚 吴昊俣 田金金 郗少杰 王巍 郭君 张�浩 倪珊珊 赵星 姜世楠 于 2021-10-26 设计创作，主要内容包括：本发明公开了一种三氟甲磺酸的制备方法,该方法为：将碱加入水中搅拌成悬浮液,然后在悬浮液中加入三氟甲磺酸三氟甲酯进行水解反应,水解反应后进行过滤去除固体杂质,得到澄清滤液；将得到的澄清滤液进行真空干燥,得到三氟甲磺酸盐；然后将得到的三氟甲磺酸盐与浓硫酸进行反应,反应后得到三氟甲磺酸粗品,将所述三氟甲磺酸粗品进行减压蒸馏,最终制得精品三氟甲磺酸。本发明中将三氟甲磺酸三氟甲酯转化为三氟甲磺酸的工艺方法,该方法能有效地将三氟甲磺酸三氟甲酯转化为具有经济价值的三氟甲磺酸产品。(The invention discloses a preparation method of trifluoromethanesulfonic acid, which comprises the following steps: adding alkali into water, stirring to form a suspension, then adding trifluoromethyl trifluoromethanesulfonate into the suspension for hydrolysis reaction, and filtering to remove solid impurities after the hydrolysis reaction to obtain clear filtrate; carrying out vacuum drying on the obtained clear filtrate to obtain trifluoromethanesulfonate; and then reacting the obtained trifluoromethanesulfonate with concentrated sulfuric acid to obtain a crude trifluoromethanesulfonic acid product, and distilling the crude trifluoromethanesulfonic acid product under reduced pressure to finally obtain a fine trifluoromethanesulfonic acid product. The process for converting trifluoromethyl trifluoromethanesulfonate into trifluoromethanesulfonic acid in the invention can effectively convert trifluoromethyl trifluoromethanesulfonate into trifluoromethanesulfonic acid product with economic value.)

1. A preparation method of trifluoromethanesulfonic acid is characterized by comprising the following steps:

s1, adding alkali into water, stirring to form a suspension, adding trifluoromethyl trifluoromethanesulfonate into the suspension for hydrolysis reaction at the reaction temperature of-10-90 ℃ and the reaction pressure of 0-0.1 MPa until the pH value of a reaction liquid of the hydrolysis reaction is neutral, and filtering to remove solid impurities after the reaction to obtain a clear filtrate; the alkali is calcium hydroxide, strontium hydroxide or barium hydroxide;

s2, carrying out vacuum drying on the clear filtrate obtained in the S1 to obtain the trifluoromethanesulfonate, wherein the vacuum degree of the vacuum drying is-0.098 MPa to-0.095 MPa, and the temperature is 50-200 ℃;

s3, reacting the trifluoromethanesulfonate obtained in the step S2 with concentrated sulfuric acid at the temperature of 60-150 ℃, obtaining a crude trifluoromethanesulfonic acid product after the reaction, and distilling the crude trifluoromethanesulfonic acid product under reduced pressure to finally obtain a refined trifluoromethanesulfonic acid product.

2. The method for preparing trifluoromethanesulfonic acid according to claim 1, wherein the hydrolysis reaction is terminated when the pH of the reaction solution in S1 is 6-7.

3. The method according to claim 1, wherein the suspension concentration in S1 is 10-40%.

4. The method according to claim 1, wherein the trifluoromethyl trifluoromethanesulfonate is added to the suspension in S1 by gas phase introduction or low-temperature dropping, wherein the low-temperature dropping is performed by controlling the temperature of the trifluoromethyl trifluoromethanesulfonate to 0-5 ℃ and the dropping rate is 1-2 drops/sec.

5. The method according to claim 1, wherein the molar ratio of the trifluoromethyl trifluoromethanesulfonate to the base in S1 is 1: (3-6).

6. The method according to claim 1, wherein the molar ratio of the triflate to concentrated sulfuric acid in S3 is 1: (4-20).

7. The method for preparing trifluoromethanesulfonic acid according to claim 1, wherein the temperature of the vacuum distillation in S3 is 60 ℃ to 170 ℃, and the vacuum degree is-0.098 MPa to-0.095 MPa.

Technical Field

The invention belongs to the technical field of chemical industry, and particularly relates to a preparation method of trifluoromethanesulfonic acid.

Background

Trifluoromethanesulfonic acid is one of the known super acids, and is widely applied to industries such as medicines and chemical engineering. Can replace inorganic acids such as sulfuric acid, hydrochloric acid and the like in various industries. The synthesis method mainly comprises the following steps: electrolytic fluorination method, CF₃SSCF₃Synthesis method and CHF₃Oxidation methods, and the like. The electrolytic fluorination method is the mainstream process at present, but the method consumes electric energy and has higher cost.

Trifluoromethanesulfonic anhydride is an important chemical intermediate, and can be used as a raw material of a cancer treatment drug abiraterone. The mainstream production process of the trifluoromethanesulfonic anhydride at present adopts a dehydration reaction of trifluoromethanesulfonic acid and phosphorus pentoxide, and the process is often accompanied by a side reaction of producing trifluoromethyl trifluoromethanesulfonate. The application field range of the trifluoromethyl trifluoromethanesulfonate is not high, and the economy is not high. But if the substance can be converted into useful chemical raw materials, the application field of the product can be expanded and the waste can be changed into valuable. The trifluoromethyl trifluoromethanesulfonate is hydrolyzed under alkaline conditions to generate a corresponding salt, and the chemical reaction equation is as follows:

CF₃SO₃OCF₃+6MOH＝CF₃SO₃M+3MF+M₂CO₃+3H₂O

however, the three salts are easily dissolved in water and are difficult to separate. At present, the common method is to dissolve organic salt by using an organic solvent after drying, filter and remove inorganic salt, and evaporate the solvent again to obtain pure trifluoromethanesulfonate. The process is complicated to operate, and the organic solvent used is high in flammability and risk, so that the industrial application is not realized. Therefore, it is important to develop a convenient method for preparing trifluoromethanesulfonic acid.

Disclosure of Invention

The technical problem to be solved by the present invention is to provide a method for preparing trifluoromethanesulfonic acid, which is directed to the above-mentioned deficiencies of the prior art. The method firstly converts the triflate into the pure triflate and then converts the triflate into the refined triflate, and has the advantages of simple process, mild reaction conditions, higher yield and good safety.

In order to solve the technical problems, the invention adopts the technical scheme that: a method for preparing trifluoromethanesulfonic acid, comprising the steps of:

s1, adding alkali into water, stirring to form a suspension, adding trifluoromethyl trifluoromethanesulfonate into the suspension for hydrolysis reaction at the reaction temperature of-10-90 ℃ and the reaction pressure of 0-0.1 MPa until the pH value of a reaction liquid of the hydrolysis reaction is neutral, and filtering to remove solid impurities after the reaction to obtain a clear filtrate; the alkali is calcium hydroxide, strontium hydroxide or barium hydroxide;

s2, carrying out vacuum drying on the clear filtrate obtained in the S1 to obtain the trifluoromethanesulfonate, wherein the vacuum degree of the vacuum drying is-0.098 MPa to-0.095 MPa, and the temperature is 50-200 ℃;

s3, reacting the trifluoromethanesulfonate obtained in the step S2 with concentrated sulfuric acid at the temperature of 60-150 ℃, obtaining a crude trifluoromethanesulfonic acid product after the reaction, and distilling the crude trifluoromethanesulfonic acid product under reduced pressure to finally obtain a refined trifluoromethanesulfonic acid product.

Preferably, the hydrolysis reaction is finished when the pH value of the reaction solution in S1 is 6-7.

Preferably, the suspension concentration in S1 is 10% to 40%.

Preferably, the method for adding the trifluoromethyl trifluoromethanesulfonate into the suspension in S1 is gas phase introduction or low-temperature dropping, wherein the low-temperature dropping is to control the temperature of the trifluoromethyl trifluoromethanesulfonate to be 0-5 ℃, and the dropping speed is 1-2 drops/second.

Preferably, the molar ratio of trifluoromethyl triflate to base in S1 is 1: (3-6).

Preferably, the molar ratio of the triflate to concentrated sulfuric acid in S3 is 1: (4-20).

Preferably, the temperature of the reduced pressure distillation in S3 is 60-170 ℃, and the vacuum degree is-0.098 MPa-0.095 MPa.

The reaction principle in S1 is:

2CF₃SO₃CF₃+6M(OH)₂＝M(CF₃SO₃)₂+3MF₂+2MCO₃+6H₂o, wherein MF₂And MCO₃Insoluble in water, M is calcium, strontium or barium.

The reaction principle in S3 is:

M(CF₃SO₃)₂+H₂SO₄＝CF₃SO₃H+M₂SO₄

compared with the prior art, the invention has the following advantages:

1. the invention adopts calcium hydroxide, strontium hydroxide or barium hydroxide to carry out hydrolysis reaction on trifluoromethyl trifluoromethanesulfonate, the calcium hydroxide, the strontium hydroxide and the barium hydroxide belong to IIA group hydroxides, and the IIA group hydroxides are directly reacted with generated F in the hydrolysis process^-And CO₃ ^2-Combined to form a precipitate, can be directly effected with CF₃SO₃ ^-The separation is realized, the pure trifluoromethanesulfonate can be directly obtained, the process is simple, and the safety is high.

2. The invention can convert trifluoromethyl trifluoromethanesulfonate which is not high in application field and low in economical efficiency into trifluoromethanesulfonic acid with economic value, and changes chemical wastes with low market demand into valuables.

The technical solution of the present invention will be described in further detail by examples.

Detailed Description

Example 1

The preparation method of trifluoromethanesulfonic acid of this example includes the following steps:

s1, adding calcium hydroxide into water, stirring to form a suspension, wherein the concentration of the suspension is 10%, then dropwise adding trifluoromethyl trifluoromethanesulfonate into the suspension at a low temperature to perform hydrolysis reaction, wherein the reaction temperature of the hydrolysis reaction is 30 ℃, the reaction pressure is 0.1MPa, the reaction is stopped until the pH value of a reaction liquid of the hydrolysis reaction is 7, and filtering is performed after the reaction to remove solid impurities, so that a clear filtrate is obtained; the molar ratio of the trifluoromethyl trifluoromethanesulfonate to the base is 1: 3;

the low-temperature dropping is to control the temperature of the trifluoromethyl trifluoromethanesulfonate to be 0 ℃, and the dropping speed is 1 drop/second;

s2, carrying out vacuum drying on the clear filtrate obtained in the S1 to obtain trifluoromethanesulfonate, wherein the vacuum degree of the vacuum drying is-0.098 Mpa, and the temperature is 170 ℃;

s3, reacting the trifluoromethanesulfonate obtained in the step S2 with concentrated sulfuric acid at the temperature of 150 ℃, obtaining a crude trifluoromethanesulfonic acid product after the reaction, and distilling the crude trifluoromethanesulfonic acid product under reduced pressure to finally obtain a refined trifluoromethanesulfonic acid product; the molar ratio of the trifluoromethanesulfonate to the concentrated sulfuric acid is 1: and 4, the temperature of the reduced pressure distillation is 60 ℃, the vacuum degree is-0.098 Mpa, and the mass fraction of the concentrated sulfuric acid is 98%.

The purity of the fine trifluoromethanesulfonic acid obtained in this example was analyzed by nuclear magnetic resonance, and the impurity ion F was analyzed by ion chromatography^-、CO₃ ^2-、SO₄ ^2-And Cl^-The contents and the results are shown in the following table.

Purity of mass	Ester residue	F-	CO3 2-	SO4 2-	Cl-
						99.5％	0.022％	855ppm	75ppm	7ppm	1ppm

Example 2

The preparation method of trifluoromethanesulfonic acid of this example includes the following steps:

s1, adding strontium hydroxide into water, stirring to form a suspension, wherein the concentration of the suspension is 20%, then adding trifluoromethyl trifluoromethanesulfonate into the suspension at a low temperature to perform hydrolysis reaction, wherein the reaction temperature of the hydrolysis reaction is 90 ℃, the reaction pressure is 0.05MPa, stopping the reaction until the pH value of a reaction liquid of the hydrolysis reaction is 6.5, and filtering to remove solid impurities after the reaction to obtain a clear filtrate; the molar ratio of the trifluoromethyl trifluoromethanesulfonate to the base is 1: 5;

the low-temperature dropping is to control the temperature of the trifluoromethyl trifluoromethanesulfonate to be 3 ℃, and the dropping speed is 2 drops per second;

s2, carrying out vacuum drying on the clear filtrate obtained in the S1 to obtain trifluoromethanesulfonate, wherein the vacuum degree of the vacuum drying is-0.096 Mpa, and the temperature is 200 ℃;

s3, reacting the trifluoromethanesulfonate obtained in the step S2 with concentrated sulfuric acid at the temperature of 80 ℃, obtaining a crude trifluoromethanesulfonic acid product after the reaction, and distilling the crude trifluoromethanesulfonic acid product under reduced pressure to finally obtain a refined trifluoromethanesulfonic acid product; the molar ratio of the trifluoromethanesulfonate to the concentrated sulfuric acid is 1: 10, the temperature of the reduced pressure distillation is 170 ℃, the vacuum degree is-0.095 Mpa, and the mass fraction of the concentrated sulfuric acid is 98%.

The purity of the fine trifluoromethanesulfonic acid obtained in this example was analyzed by nuclear magnetic resonance, and the impurity ion F was analyzed by ion chromatography^-、CO₃ ^2-、SO₄ ^2-And Cl^-The contents and the results are shown in the following table.

Purity of mass	Ester residue	F-	CO3 2-	SO4 2-	Cl-
						98.2％	0.035％	453ppm	12ppm	45ppm	17ppm

Example 3

The preparation method of trifluoromethanesulfonic acid of this example includes the following steps:

s1, adding barium hydroxide into water, stirring to form a suspension, wherein the concentration of the suspension is 40%, then adding trifluoromethyl trifluoromethanesulfonate into the suspension at a low temperature for hydrolysis reaction, wherein the reaction temperature of the hydrolysis reaction is-10 ℃, the reaction pressure is 0MPa, the reaction is stopped until the pH value of a reaction liquid of the hydrolysis reaction is 6, and filtering to remove solid impurities after the reaction to obtain a clear filtrate; the molar ratio of the trifluoromethyl trifluoromethanesulfonate to the base is 1: 6;

the low-temperature dropping is to control the temperature of the trifluoromethyl trifluoromethanesulfonate to be 5 ℃, and the dropping speed is 1 drop/second;

s2, carrying out vacuum drying on the clear filtrate obtained in the S1 to obtain trifluoromethanesulfonate, wherein the vacuum degree of the vacuum drying is-0.095 Mpa, and the temperature is 50 ℃;

s3, reacting the trifluoromethanesulfonate obtained in the step S2 with concentrated sulfuric acid at the temperature of 60 ℃ to obtain a crude trifluoromethanesulfonic acid product, and distilling the crude trifluoromethanesulfonic acid product under reduced pressure to finally obtain a refined trifluoromethanesulfonic acid product; the molar ratio of the trifluoromethanesulfonate to the concentrated sulfuric acid is 1: 20, the temperature of the reduced pressure distillation is 120 ℃, the vacuum degree is-0.096 Mpa, and the mass fraction of the concentrated sulfuric acid is 98%.

The purity of the fine trifluoromethanesulfonic acid obtained in this example was analyzed by nuclear magnetic resonance, and the impurity ion F was analyzed by ion chromatography^-、CO₃ ^2-、SO₄ ^2-And Cl^-The contents and the results are shown in the following table.

Purity of mass	Ester residue	F-	CO3 2-	SO4 2-	Cl-
						99.1％	0.014％	255ppm	13ppm	23ppm	11ppm

Example 4

The preparation method of trifluoromethanesulfonic acid of this example includes the following steps:

s1, adding calcium hydroxide into water, stirring to form a suspension, wherein the concentration of the suspension is 30%, then introducing trifluoromethyl trifluoromethanesulfonate gas phase into the suspension for hydrolysis reaction, wherein the reaction temperature of the hydrolysis reaction is 80 ℃, the reaction pressure is 0.1MPa, stopping the reaction until the pH value of the reaction liquid of the hydrolysis reaction is 7, and filtering to remove solid impurities after the reaction to obtain clear filtrate; the molar ratio of the trifluoromethyl trifluoromethanesulfonate to the base is 1: 4;

the low-temperature dropping is to control the temperature of the trifluoromethyl trifluoromethanesulfonate to be 4 ℃, and the dropping speed is 2 drops per second;

s2, carrying out vacuum drying on the clear filtrate obtained in the S1 to obtain trifluoromethanesulfonate, wherein the vacuum degree of the vacuum drying is-0.097 Mpa, and the temperature is 120 ℃;

s3, reacting the trifluoromethanesulfonate obtained in the step S2 with concentrated sulfuric acid at the temperature of 100 ℃, obtaining a crude trifluoromethanesulfonic acid product after the reaction, and distilling the crude trifluoromethanesulfonic acid product under reduced pressure to finally obtain a refined trifluoromethanesulfonic acid product; the molar ratio of the trifluoromethanesulfonate to the concentrated sulfuric acid is 1: 7, the temperature of the reduced pressure distillation is 150 ℃, the vacuum degree is-0.097 Mpa, and the mass fraction of the concentrated sulfuric acid is 98%.

The purity of the fine trifluoromethanesulfonic acid obtained in this example was analyzed by nuclear magnetic resonance and impurities were analyzed by ion chromatographyProton ion F^-、CO₃ ^2-、SO₄ ^2-And Cl^-The contents and the results are shown in the following table.

Purity of mass	Ester residue	F-	CO3 2-	SO4 2-	Cl-
						99.3％	0.002％	134ppm	34ppm	16ppm	11ppm

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention in any way. Any simple modification, change and equivalent changes of the above embodiments according to the technical essence of the invention are still within the protection scope of the technical solution of the invention.