Preparation method of sulfuryl fluoride chloride

Abstract

The invention provides a method for preparing sulfuryl fluoride chloride by an electrolytic process, which comprises the following steps: introducing sulfuryl chloride and hydrogen fluoride into an electrolytic bath, adding a conductive additive, and introducing direct current for electrolysis to obtain the sulfuryl fluoride chloride in one step, according to the method, reaction can be performed at normal temperature and normal pressure, by-product impurities such as sulfamic acid are not generated, the product purity is relatively high, and continuous production can be realized.

Description

Technical Field

[0001] The present invention relates to an improved chemical synthesis method, in particular to a method for preparing sulfuryl fluoride (SO2ClF). Background Art

[0002] In the field of organic synthesis, sulfuryl fluoride (SO2ClF) plays a key role as an important intermediate compound. It is widely used in a variety of organic synthesis reactions, especially in the preparation of fluorination reagents such as lithium bis(fluorosulfonyl)imide, which has significant application potential, especially in improving the thermal stability and electrochemical stability of electrolytes. Lithium bis(fluorosulfonyl)imide is an efficient fluorination reagent, and its application in organic synthesis has been widely recognized. It can achieve efficient and selective fluorination reactions, which is of great significance to the fields of drug synthesis, materials science and fine chemical preparation. As a precursor of lithium bis(fluorosulfonyl)imide, the preparation of sulfuryl fluoride is crucial to meet the needs of industrial production and laboratory research.

[0003] However, in traditional methods, the preparation of sulfuryl fluoride is usually based on the reaction of sulfuryl chloride (SO2Cl2) and a fluorination agent. These methods have some disadvantages, such as:

[0004] Waste generation: Traditional methods often produce a large amount of waste, including hydrogen chloride and sulfuric acid, which is not conducive to environmental protection;

[0005] Harsh reaction conditions: Traditional preparation methods usually require harsh reaction conditions such as high temperature and high pressure, which not only consumes a lot of energy, but also makes the reaction process difficult to control;

[0006] The product purity is low: Due to the limitations of reaction conditions, the sulfuryl fluoride chloride products obtained by traditional methods are often of low purity. The by-product aminosulfonic acid has a great negative impact on product application, requiring cumbersome purification steps, which greatly increases costs.

[0007] Sulfuryl fluoride has a wide range of applications in the field of organic synthesis, the most notable of which is that it can be used as a synthetic intermediate for lithium bis(fluorosulfonylimide) to prepare triethylamine bis(fluorosulfonylimide) salt. It does not produce additional hydrogen fluoride salt, but instead produces triethylamine hydrochloride (solid is easier to separate), which is safer, more efficient and less costly.

[0008] Therefore, this patent aims to provide an optimized method for preparing sulfuryl fluoride chloride to improve its production efficiency, product quality and environmental friendliness, thereby meeting the demand for high-quality sulfuryl fluoride chloride in the field of organic synthesis and promoting its widespread application in the preparation of important chemicals such as lithium bis(fluorosulfonyl)imide. Summary of the invention

[0009] In view of the above problems existing in the prior art, the present invention provides a new method for preparing sulfuryl fluoride chloride to improve its production efficiency, product quality and environmental friendliness, thereby meeting the demand for high-quality sulfuryl fluoride chloride in the field of organic synthesis; the sulfuryl fluoride chloride produced by the method is safer and more efficient for preparing bis(fluorosulfonylimide) triethylamine salt, thereby promoting its wide application in the preparation of important chemicals such as bis(fluorosulfonylimide) lithium.

[0010] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solution:

[0011] The invention provides a method for preparing sulfuryl fluoride chlorine. The method comprises: introducing sulfuryl chloride and hydrogen fluoride into an electrolytic cell, adding a conductive auxiliary agent, and introducing direct current for electrolysis to obtain sulfuryl fluoride chlorine.

[0012] In some specific embodiments, it is preferred to place hydrogen fluoride in a de-doping electrolytic cell for de-doping electrolysis before electrolysis. The electrodes of the de-doping electrolytic cell are not particularly limited as long as they are metal electrodes that can withstand HF corrosion, preferably all-nickel electrodes and / or monel electrodes.

[0013] The shell material of the electrolytic cell is a material that can withstand HF corrosion, preferably one or more of PTFE lining, PTFE lining, PFA lining, and full PFA; the impurity removal electrolysis current density is 1000-3000A / m 2 , for example 1200A / m 2 、1400A / m 2 、1600A / m 2 、1800A / m 2 、2000A / m 2 、2200A / m 2 、2400A / m 2 、2600A / m 2 , 2800, preferably 1500-2500A / m 2 ; The impurity removal electrolysis voltage is 1 to 20 V, for example 2V, 3V, 4V, 5V, 6V, 7V, 8V, 9V, 10V, 11V, 12V, 13V, 14V, 15V, 16V, 17V, 18V, 19V, preferably 2 to 5V; The impurity removal electrolysis temperature is -20 to 50°C, for example -15°C, -10°C, -5°C, 0°C, 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, preferably 0 to 15°C; The impurity removal electrolysis time is 1 to 60 min, for example 10 min, 20 min, 30 min, 40 min, 50 min; preferably 10 to 30 min.

[0014] In some specific embodiments, the reaction electrolytic cell electrodes can be metal electrodes that can withstand HF corrosion, preferably: all-nickel electrodes and / or monel electrodes; the electrolytic cell shell material can be any material that can withstand HF corrosion, preferably: one or more of PTFE lining, all PTFE material, PFA lining, and all PFA; the current density is 1000-3000A / m 2 , for example 1200A / m 2 、1400A / m 2 、1600A / m 2 、1800A / m 2 、2000A / m 2 、2200A / m 2 、2400A / m 2 、2600A / m 2 , 2800, preferably 1500-2500A / m 2 ; The voltage is 1 to 20 V, for example 2V, 3V, 4V, 5V, 6V, 7V, 8V, 9V, 10V, 11V, 12V, 13V, 14V, 15V, 16V, 17V, 18V, 19V, preferably 5 to 8V, and the temperature is 5 to 50°C, for example 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, preferably 10 to 25°C.

[0015] In some specific embodiments, the conductive additive in the reaction electrolytic cell is a fluorine-containing alkali metal salt, preferably one or more of fluorine-containing metal salts such as sodium fluoride, potassium fluoride, and lithium fluoride, and more preferably one or two of sodium fluoride and potassium fluoride. The amount of the conductive additive added is 0.1wt% to 5wt% of the total mass of the initial reaction solution, preferably 0.5wt% to 1.5wt%.

[0016] In some specific embodiments, the purity of sulfuryl chloride is 98wt% to 99.999wt%, preferably 99wt% to 99.9wt%; and its addition per minute is 0.1% to 5% of the total mass of the initial reaction solution, preferably 1% to 2%.

[0017] The total mass of the initial reaction solution is the total pre-added amount of sulfuryl chloride and hydrogen fluoride in the initial electrolytic cell.

[0018] Cathode: 2H + +2e - =H2; Anode: SO2Cl2+2F - -2e - =SO2FCl+ClF

[0019] Total: SO2Cl2+2HF→SO2FCl+ClF+H2

[0020] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0021] The preparation method of the present invention can obtain high-purity sulfuryl fluoride chloride in one step, which can be directly used as an intermediate of various high value-added chemicals; the reaction temperature and pressure are low, the conversion rate is fast, and the product purity is high; the synthesis intermediate of lithium bis(fluorosulfonyl)imide is used to prepare triethylamine salt of bis(fluorosulfonyl)imide, and the generated impurities are very few, and no additional hydrogen fluoride salt is generated, instead of triethylamine hydrochloride of hydrogen chloride (solid is easier to separate), which is safer, more efficient, and has lower cost. The preparation process has mild conditions, the reaction can occur at room temperature, the by-product waste is less, and the environmental pollution is small. DETAILED DESCRIPTION

[0022] In order to better understand the technical solution of the present invention, the content of the present invention is further described below in conjunction with the embodiments, but the content of the present invention is not limited to the following embodiments.

[0023] Sources of the main raw materials used in the examples of the present invention, unless otherwise specified, are common commercially available raw materials:

[0024] Sulfuryl chloride: Manufacturer: Inotech, Product No.: GC10297, purity > 99%;

[0025] Sodium fluoride: Manufacturer: Inokai, Product No.: 201290025, purity > 99%;

[0026] Potassium fluoride: Manufacturer: Inokai, Product No.: 010980, purity > 99%;

[0027] Lithium fluoride: Manufacturer: Inotech, Product No.: A81758, purity >99%.

[0028] Unless otherwise specified, the experimental operations involved in the following examples or comparative examples are all conventional experimental methods in the art.

[0029] The analysis method is a conventional method in the industry.

[0030] Example 1

[0031] Impurity removal electrolytic cell conditions: All-nickel electrode, current density 2000A / m 2 The voltage is 4V, the temperature is 10°C, and the electrolysis time is 20min. 2000g of hydrogen fluoride is introduced into the PTFE electrolytic cell in advance, and the cell temperature is controlled at 10°C. After the electrolysis is completed, 1000g of hydrogen fluoride after impurities are removed is transferred to the reaction electrolytic cell for standby use.

[0032] Reaction electrolytic cell conditions: All nickel electrodes, current density 200A / m 2, voltage 7V, temperature 12℃, sodium fluoride addition amount 10g, sulfuryl chloride (99.9%) introduction rate maintained at: 15g / min; the reflux condensation temperature of sulfuryl fluoride outlet is controlled at 10℃, the liquid holding capacity of the reaction electrolytic cell is observed, hydrogen fluoride is continuously added to maintain the reaction balance, the condensate at the outlet is collected, and the purity of sulfuryl fluoride is measured: 99.9%.

[0033] Example 2

[0034] Impurity removal electrolytic cell conditions: electrode monel electrode, current density 1000A / m 2 The voltage is 1V, the temperature is -20°C, and the electrolysis time is 10min. 2000g of hydrogen fluoride is introduced into the PTFE electrolytic cell in advance, and the cell temperature is controlled at -20°C. After the electrolysis is completed, 1000g of the hydrogen fluoride after impurities are removed is transferred to the reaction electrolytic cell for standby use.

[0035] Reaction electrolytic cell conditions: All nickel electrodes, current density 1000A / m 2 , voltage 5V, temperature 5℃, potassium fluoride addition amount 1g, sulfuryl chloride (98.0%) introduction rate maintained at: 1g / min; the reflux condensation temperature of sulfuryl fluoride outlet is controlled at 10℃, the liquid holding capacity of the reaction electrolytic cell is observed, hydrogen fluoride is continuously added to maintain the reaction balance, the condensate at the outlet is collected, and the sulfuryl fluoride purity is measured to be: 96.59%.

[0036] Example 3

[0037] Impurity removal electrolytic cell conditions: All-nickel electrode, current density 1500A / m 2 The voltage is 20V, the temperature is 15°C, and the electrolysis time is 20min. 2000g of hydrogen fluoride is introduced into the PTFE electrolytic cell in advance, and the cell temperature is controlled at 15°C. After the electrolysis is completed, 1000g of hydrogen fluoride after impurities are removed is transferred to the reaction electrolytic cell for standby use.

[0038] Reaction electrolytic cell conditions: All nickel electrodes, current density 2500A / m 2 , voltage 1V, temperature 10℃, lithium fluoride addition amount 5g, sulfuryl chloride (99.99%) introduction rate maintained at: 20g / min; the reflux condensation temperature of the sulfuryl fluoride outlet was controlled at 10℃, the liquid holding capacity of the reaction electrolytic cell was observed, hydrogen fluoride was continuously added to maintain the reaction balance, the condensate at the outlet was collected, and the sulfuryl fluoride purity was measured to be: 97.2%.

[0039] Example 4

[0040] Impurity removal electrolytic cell conditions: electrode monel electrode, current density 3000A / m 2The voltage is 5V, the temperature is 0℃, and the electrolysis time is 60min. 2000g of hydrogen fluoride is introduced into the PTFE electrolytic cell in advance, and the cell temperature is controlled at 0℃. After the electrolysis is completed, 1000g of hydrogen fluoride after impurities removal is transferred to the reaction electrolytic cell for standby use.

[0041] Reaction electrolytic cell conditions: All nickel electrodes, current density 3000A / m 2 , voltage 20V, temperature 50℃, sodium fluoride addition amount 15g, sulfuryl chloride (99.0%) introduction rate maintained at: 10g / min; the reflux condensation temperature of sulfuryl fluoride outlet is controlled at 10℃, the liquid holding capacity of the reaction electrolytic cell is observed, hydrogen fluoride is continuously added to maintain the reaction balance, the condensate at the outlet is collected, and the sulfuryl fluoride purity is measured to be: 96.3%.

[0042] Example 5

[0043] Impurity removal electrolytic cell conditions: All-nickel electrode, current density 2500A / m 2 The voltage is 2V, the temperature is 50°C, and the electrolysis time is 30min. 2000g of hydrogen fluoride is introduced into the PTFE electrolytic cell in advance, and the cell temperature is controlled at 50°C. After the electrolysis is completed, 1000g of hydrogen fluoride after impurities are removed is transferred to the reaction electrolytic cell for standby use.

[0044] Reaction electrolytic cell conditions: All nickel electrodes, current density 1500A / m 2 , voltage 8V, temperature 25℃, potassium fluoride addition amount 50g, sulfuryl chloride (98.5%) introduction rate maintained at: 30g / min; the reflux condensation temperature of sulfuryl fluoride outlet is controlled at 10℃, the liquid holding capacity of the reaction electrolytic cell is observed, hydrogen fluoride is continuously added to maintain the reaction balance, the condensate at the outlet is collected, and the sulfuryl fluoride purity is measured to be: 97.6%.

[0045] Comparative Example 1

[0046] Weigh 1000 g of sulfuryl chloride (99.99%) and add it to the reactor. Heat it to 100°C, then slowly drop HF: 296.3 g, and continue the reaction for 8 hours. The reflux condensation temperature at the outlet is 10°C. The purity of the product sulfuryl fluoride is measured to be 20.6%.

[0047] Those skilled in the art will appreciate that, based on the teachings of this specification, some modifications or adjustments may be made to the present invention, and these modifications or adjustments should also be within the scope defined by the claims of the present invention.

Claims

1. A method for preparing sulfuryl fluoride chloride, the method comprising: Sulfuryl chloride and hydrogen fluoride are introduced into a reaction electrolytic cell, a conductive aid is added, and direct current is introduced for electrolysis to obtain sulfuryl fluoride chloride.

2. The preparation method according to claim 1, characterized in that Before electrolysis, hydrogen fluoride is placed in an impurity removal electrolytic cell for impurity removal electrolysis, wherein the electrodes of the impurity removal electrolytic cell are all-nickel electrodes and / or monel electrodes.

3. The preparation method according to claim 1 or 2, characterized in that: The impurity removal electrolysis current density is 1000-3000A / m 2 , preferably 1500~2500A / m 2 ; and / or, the impurity removal electrolysis voltage is 1 to 20V, preferably 2 to 5V.

4. The preparation method according to any one of claims 1 to 3, characterized in that: The impurity removal electrolysis temperature is -20 to 50°C, preferably 0 to 15°C; and / or the impurity removal electrolysis time is 1 to 60 min, preferably 10 to 30 min.

5. The preparation method according to any one of claims 1 to 4, characterized in that: The reaction electrolytic cell electrodes are all-nickel electrodes and / or monel electrodes; and / or the electrolytic cell shell material is one or more of: PTFE-lined, all-PTFE material, PFA-lined, and all-PFA.

6. The preparation method according to any one of claims 1 to 5, characterized in that: The electrolysis current density is 1000-3000A / m 2 , preferably 1500~2500A / m 2 ; and / or, the voltage is 1 to 20 V, preferably 5 to 8 V; and / or, the temperature is 5 to 50°C, preferably 10 to 25°C.

7. The preparation method according to any one of claims 1 to 6, characterized in that: The conductive aid is a fluorine-containing alkali metal salt, preferably one or more fluorine-containing metal salts such as sodium fluoride, potassium fluoride, lithium fluoride, etc., more preferably one or both of sodium fluoride and potassium fluoride; and / or, the conductive aid is added in an amount of 0.1wt% to 5wt% of the total mass of the initial reaction solution, preferably 0.5wt% to 1.5wt%.