A preparation method and application of fluorosulfonate

Abstract

The present invention discloses a preparation method of fluorosulfonate, and the steps include the following several steps: (1) preparing a non-aqueous solvent solution of sulfonyl fluoride; (2) adding a metal source in portions for reaction; (3) adding a poor solvent to the reaction solution; (4) recrystallizing and drying. Compared with the prior art methods, the preparation method of fluorosulfonate in the present invention application avoids the product adsorption caused by the presence of carboxylic acid in the by-products, and can efficiently obtain high-purity fluorosulfonate through simple conventional operations under mild conditions without cumbersome purification steps. The prepared fluorosulfonate has excellent yield and purity, high utilization efficiency of raw materials, easy operation of the reaction, simple process, reduces the output of pollutants and by-products, and has broad development prospects.

Description

Technical Field

[0001] The present invention relates to the field of chemicals, and particularly to a preparation method and application of fluorosulfonate. Background Art

[0002] Non-aqueous electrolyte secondary batteries such as lithium secondary batteries are being put into practical use in a wide range of applications, from so-called civilian power sources such as mobile phones and laptop computers to in-vehicle power sources for driving vehicles such as cars and large stationary power sources. However, in recent years, there has been an increasing demand for high performance of non-aqueous electrolyte secondary batteries, and battery characteristics such as high capacity, high output, high-temperature storage characteristics, and cycle characteristics are required to reach a high level.

[0003] In particular, when a lithium secondary battery is used as a power source for an electric vehicle, since the electric vehicle requires a large amount of energy during startup and acceleration and must effectively regenerate the high energy generated during deceleration, the lithium secondary battery is required to have high output characteristics and input characteristics. Currently, for the non-aqueous electrolyte of a lithium secondary battery, it is required to have an initial capacity, high input-output characteristics, low internal impedance of the battery, a high capacity retention rate after durability tests such as high-temperature storage tests or cycle tests, and excellent input-output performance and impedance characteristics after the durability test.

[0004] As a high-quality non-aqueous electrolyte for lithium secondary batteries, fluorosulfonate can better solve the above problems. In the prior art, the main preparation methods of fluorosulfonate include the following main methods: (1) a method of reacting fluorosulfonic acid or sulfur trioxide with a halide salt in anhydrous hydrofluoric acid to obtain fluorosulfonate; (2) a method of reacting fluorosulfonic acid with a carboxylate salt or a halide salt; (3) a method of mixing ammonium fluorosulfate and an aqueous hydroxide solution to obtain a trihydrate of fluorosulfonate. However, substances such as sulfur trioxide and fluorosulfonic acid used in these reactions are highly corrosive, and corrosive sulfuric acid and hydrogen fluoride will be generated, which not only causes corrosion of equipment and environmental pollution, but also is difficult to operate in actual production. For method (3), after synthesizing the ammonium salt, cation exchange of the metal salt is also required, and the operation is too cumbersome and ammonia detachment is likely to be mixed in.

[0005] Therefore, there is an urgent need for a preparation method of fluorosulfonate that is simple to operate, conducive to production, has few by-products, mild production conditions, and high yield and purity of the product. Summary of the Invention

[0006] To solve the above problems, the first aspect of the present invention provides a preparation method of fluorosulfonate, and the steps include the following: (1) preparing a non-aqueous solvent solution of sulfonyl fluoride; (2) adding a metal source in portions for reaction; (3) adding a poor solvent to the reaction solution; (4) recrystallizing and drying.

[0007] As a preferred embodiment, the specific operation of preparing the non-aqueous solvent solution of sulfonyl fluoride is as follows: Replace the reaction vessel with nitrogen, add a non-aqueous solvent to the reaction vessel, control the temperature, and slowly introduce sulfonyl fluoride gas into the reaction vessel to obtain the non-aqueous solvent solution of sulfonyl fluoride.

[0008] As a preferred embodiment, the metal source is at least one of carbonate, bicarbonate, hydroxide, sulfate, phosphate, metal hydride, and elemental metal; the metal type of the metal source is at least one of sodium, potassium, lithium, iron, calcium, and magnesium.

[0009] As a preferred embodiment, the molar ratio of sulfonyl fluoride to the metal source is 1:0.4 - 1.5.

[0010] As a preferred embodiment, the overall reaction temperature of the preparation method of the fluorosulfonate is -30°C to 120°C.

[0011] As a preferred embodiment, the temperature for preparing the non-aqueous solvent solution of sulfonyl fluoride is -30°C to 120°C.

[0012] As a preferred embodiment, the non-aqueous solvent is at least one of carboxylic acid esters, chain carbonates, cyclic carbonates, nitriles, halogenated alkanes, aromatic alkanes, and ethers; the carboxylic acid esters are ethyl acetate, methyl acetate, methyl formate, isopropyl acetate, and butyl acetate; the chain carbonates are at least one of ethyl methyl carbonate, dimethyl carbonate, and diethyl carbonate; the cyclic carbonates are ethylene carbonate, propylene carbonate, and vinylene carbonate; the nitriles are acetonitrile; the ethers are at least one of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, methyl tert-butyl ether, diisopropyl ether, ether, n-butyl ether, 1,4-dioxane, and tetrahydrofuran.

[0013] As a preferred embodiment, the poor solvent is at least one of aliphatic hydrocarbons and aromatic hydrocarbons; the aliphatic hydrocarbons are at least one of dichloromethane, 1,2-dichloroethane, 1,2,3-trichloropropane, and 1,1,2,2-tetrachloroethane; the aromatic hydrocarbons are at least one of toluene, xylene, trimethylbenzene, chlorobenzene, dichlorobenzene, and trichlorobenzene.

[0014] As a preferred embodiment, the mass ratio of the non-aqueous solvent to the poor solvent is 1:2 - 4.

[0015] The second aspect of the present invention provides an application of the above preparation method of fluorosulfonate, including the application of the preparation method of fluorosulfonate in the preparation process of high-purity fluorosulfonate.

[0016] Beneficial effects:

[0017] 1. Compared with the existing methods, the preparation method of fluorosulfonate in this invention application does not use raw materials such as sulfur trioxide and fluorosulfonic acid that are prone to produce corrosive substances, reducing the danger in the production process and environmental pollution, and also lowering the requirements for reaction equipment.

[0018] 2. Compared with the method of preparing fluorosulfonate by reacting fluorosulfonic acid and carboxylate, the preparation method of fluorosulfonate in this invention application avoids the product adsorption caused by the presence of carboxylic acid in the by-products, and further improves the purity of the product.

[0019] 3. Compared with the method of obtaining the trihydrate of fluorosulfonate by mixing ammonium fluorosulfonate and aqueous hydroxide solution, the preparation method of fluorosulfonate in this invention application can efficiently obtain high-purity fluorosulfonate through simple conventional operations under mild conditions without the need for cumbersome purification steps. Detailed Description of the Invention

[0020] The content of the present invention can be more easily understood by referring to the following detailed description of the preferred embodiments of the present invention and the included examples. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, the definitions in this specification shall prevail.

[0021] As used herein, the term "prepared from" is synonymous with "comprising". The terms "comprising", "including", "having", "containing" or any other variation thereof used herein are intended to cover non-exclusive inclusion. For example, a composition, step, method, article or device containing the listed elements is not necessarily limited to those elements, but may include other elements not expressly listed or elements inherent to such composition, step, method, article or device.

[0022] The connecting phrase "consisting of" excludes any unstated element, step or component. If used in a claim, this phrase will render the claim closed, excluding materials other than those described, except for conventional impurities associated therewith. When the phrase "consisting of" appears in a clause of the claim body rather than immediately following the subject, it only limits the elements described in that clause; other elements are not excluded from the claim as a whole.

[0023] When an equivalent, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper preferred values and lower preferred values, this should be understood to specifically disclose all ranges formed by any pairing of any range upper limit or preferred value with any range lower limit or preferred value, regardless of whether the range is disclosed individually. For example, when the range "1 to 5" is disclosed, the described range should be interpreted to include ranges "1 to 4", "1 to 3", "1 to 2", "1 to 2 and 4 to 5", "1 to 3 and 5", etc. When a numerical range is described herein, unless otherwise stated, the range is intended to include its endpoint values and all integers and fractions within the range.

[0024] The singular form includes plural referents unless the context clearly dictates otherwise. "Optional" or "any one" means that the event or circumstance described thereafter may or may not occur, and the description includes both the case where the event occurs and the case where the event does not occur.

[0025] Approximating language, as used in the specification and claims, is used to modify a quantity and indicates that the present invention is not limited to the specific quantity but also includes a modified portion that is close to the quantity and is acceptable without causing a change in the relevant basic function. Accordingly, modifying a numerical value with "about", "approximately", etc. means that the present invention is not limited to the exact numerical value. In some instances, the approximating language may correspond to the precision of the instrument for measuring the numerical value. In the specification and claims of the present application, range limitations may be combined and / or interchanged, and if not otherwise stated, these ranges include all sub-ranges subsumed therein.

[0026] Furthermore, the indefinite articles "a" and "an" before an element or component of the present invention do not limit the quantity requirement (i.e., the number of occurrences) of the element or component. Thus, "a" or "an" should be construed to include one or at least one, and an element or component in the singular form also includes the plural form, unless the quantity clearly refers to the singular form.

[0027] To solve the above problems, a first aspect of the present invention provides a method for preparing a fluorosulfonate, the steps comprising the following: (1) preparing a non-aqueous solvent solution of sulfonyl fluoride; (2) adding a metal source in portions for reaction; (3) adding a poor solvent to the reaction solution; (4) recrystallizing and drying.

[0028] In some preferred embodiments, the specific operation for preparing the non-aqueous solvent solution of sulfonyl fluoride is as follows: displacing the reaction vessel with nitrogen, adding a non-aqueous solvent to the reaction vessel, controlling the temperature, and slowly introducing sulfonyl fluoride gas into the reaction vessel to obtain a non-aqueous solvent solution of sulfonyl fluoride.

[0029] In some preferred embodiments, the metal source is at least one of carbonate, bicarbonate, hydroxide, sulfate, phosphate, metal hydride, and elemental metal; the metal type of the metal source is at least one of sodium, potassium, lithium, iron, calcium, and magnesium.

[0030] In some preferred embodiments, the molar ratio of the sulfonyl fluoride to the metal source is 1:0.4 to 1.5.

[0031] In some preferred embodiments, the molar ratio of the sulfonyl fluoride to the metal source is 1:0.45 to 1.

[0032] In some preferred embodiments, the overall reaction temperature of the method for preparing the fluorosulfonate is -30°C to 120°C.

[0033] In some preferred embodiments, the overall reaction temperature of the method for preparing the fluorosulfonate is 0°C to 10°C.

[0034] In some preferred embodiments, the temperature of the non-aqueous solvent solution for preparing the sulfonyl fluoride is -30°C to 120°C.

[0035] In some preferred embodiments, the temperature of the non-aqueous solvent solution for preparing the sulfonyl fluoride is 0°C to 10°C.

[0036] In some preferred embodiments, the number of times of adding the metal source in portions in the reaction of adding the metal source in portions is 3 to 5 times.

[0037] In some preferred embodiments, the reaction time in the reaction of adding the metal source in portions is 2 to 4 hours.

[0038] In some preferred embodiments, before adding the poor solvent in step (3), there is also a step of removing a small amount of insoluble substances in the reaction solution through a membrane filter.

[0039] In some preferred embodiments, the pore size of the filter membrane in the membrane filter is 0.2 to 0.25 μm.

[0040] In some preferred embodiments, the non-aqueous solvent is at least one of carboxylic acid esters, chain carbonates, cyclic carbonates, nitriles, halogenated alkanes, aromatic alkanes, and ethers; the carboxylic acid esters are ethyl acetate, methyl acetate, methyl formate, isopropyl acetate, and butyl acetate; the chain carbonates are at least one of ethyl methyl carbonate, dimethyl carbonate, and diethyl carbonate; the cyclic carbonates are ethylene carbonate, propylene carbonate, and vinylene carbonate; the nitriles are acetonitrile; the ethers are at least one of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, methyl tert-butyl ether, diisopropyl ether, ethyl ether, n-butyl ether, 1,4-dioxane, and tetrahydrofuran.

[0041] In some preferred embodiments, the poor solvent is at least one of aliphatic hydrocarbons and aromatic hydrocarbons; the aliphatic hydrocarbon is at least one of dichloromethane, 1,2-dichloroethane, 1,2,3-trichloropropane, 1,1,2,2-tetrachloroethane; the aromatic hydrocarbon is at least one of toluene, xylene, mesitylene, chlorobenzene, dichlorobenzene, trichlorobenzene.

[0042] In some preferred embodiments, the mass ratio of the non-aqueous solvent to the poor solvent is 1:2 to 4.

[0043] In some preferred embodiments, the mass ratio of the non-aqueous solvent to the poor solvent is 1:2.6 to 3.6.

[0044] The second aspect of the present invention provides an application of the above-mentioned preparation method of fluorosulfonate, including the application of the preparation method of the fluorosulfonate in the preparation process of high-purity fluorosulfonate.

[0045] Examples

[0046] The technical solution of the present invention will be described in detail below through examples, but the protection scope of the present invention is not limited to all the examples described. Unless otherwise specified, the raw materials of the present invention are all commercially available.

[0047] Example 1: Preparation of Lithium Fluorosulfate

[0048] (1) The 500 ml reaction vessel was purged with nitrogen three times. 100 g of dry diethyl carbonate was charged into the reaction vessel, and the temperature was lowered to 0 °C. 0.6178 mol of sulfuryl fluoride gas was slowly introduced into it to form a sulfuryl fluoride solution in diethyl carbonate; (2) The temperature was controlled at 0 °C, and 0.5560 mol of lithium hydroxide monohydrate was added to the reaction vessel in four portions, and the reaction was carried out for 3 hours; (3) After the reaction was completed, a small amount of insoluble substances in the reaction solution were removed through a membrane filter with a membrane pore size of 0.22 μm; 300 g of dry 1,2-dichloroethane was added; (4) The temperature was lowered to 5 °C for filtration and crystallization to obtain a wet product of lithium fluorosulfonate. After drying, 53 g of high-purity lithium fluorosulfonate was obtained, with a detected purity of 99.9%, a sulfate content of 11 ppm, and an acid value of 32 ppm (calculated as HF).

[0049] Example 2: Preparation of Potassium Fluorosulfate

[0050] (1) The 500 ml reaction vessel was purged with nitrogen three times. 120 g of dry ethyl acetate was added to the reaction vessel, and the temperature was lowered to 5°C. 0.6390 mol of sulfuryl fluoride gas was slowly introduced into it to prepare a sulfuryl fluoride ethyl acetate solution. (2) With the temperature controlled at 5°C, 0.3000 mol of anhydrous potassium carbonate was added to the reaction vessel in four portions, and the reaction was carried out for 3 hours. (3) After the reaction was completed, a small amount of insoluble substances in the reaction solution were removed through a membrane filter with a membrane pore size of 0.22 μm; 360 g of dry toluene was added. (4) The temperature was lowered to 5°C for filtration and crystallization to obtain wet potassium fluorosulfate. After drying, 75.5 g of high-purity potassium fluorosulfate was obtained, with a purity of 99.9%, a sulfate radical content of 19 ppm, and an acid value of 25 ppm (calculated as HF).

[0051] Example 3: Preparation of Sodium Fluorosulfate

[0052] (1) The 500 ml reaction vessel was purged with nitrogen three times. 100 g of dry ethylene glycol dimethyl ether was added to the reaction vessel, and the temperature was lowered to 10°C. 0.2816 mol of sulfuryl fluoride gas was slowly introduced into it to prepare a sulfuryl fluoride ethylene glycol dimethyl ether solution. (2) With the temperature controlled at 10°C, 0.2534 mol of 60% anhydrous sodium hydride was added to the reaction vessel in four portions, and the reaction was carried out for 3 hours. (3) After the reaction was completed, a small amount of insoluble substances in the reaction solution were removed through a membrane filter with a membrane pore size of 0.22 μm; 360 g of chlorobenzene was added. (4) The temperature was lowered to 5°C for filtration and crystallization to obtain wet sodium fluorosulfate. After drying the wet sodium fluorosulfate, 27.5 g of high-purity sodium fluorosulfate was obtained, with a purity of 99.9%, a sulfate radical content of 14 ppm, and an acid value of 28 ppm (calculated as HF).

[0053] Example 4: Preparation of Lithium Fluorosulfate

[0054] (1) The 500 ml reaction vessel was purged with nitrogen three times. 100 g of dry acetonitrile was added to the reaction vessel, and the temperature was lowered to 5°C. 0.3341 mol of sulfuryl fluoride gas was slowly introduced into it to prepare a sulfuryl fluoride acetonitrile solution. (2) With the temperature controlled at 5°C, 0.3007 mol of anhydrous lithium carbonate was added to the reaction vessel in four portions, and the reaction was carried out for 3 hours. (3) After the reaction was completed, a small amount of insoluble substances in the reaction solution were removed through a membrane filter with a membrane pore size of 0.22 μm; 300 g of dichloromethane was added. (4) The temperature was lowered to 5°C for filtration and crystallization to obtain wet lithium fluorosulfate; after drying, high-purity lithium fluorosulfate was obtained, with a purity of 99.9%, a sulfate radical content of 14 ppm, and an acid value of 45 ppm (calculated as HF).

[0055] Finally, it is pointed out that the above-described embodiments are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for preparing fluorosulfonate, characterized in that: The steps include the following: (1) preparing a non-aqueous solvent solution of sulfonyl fluoride; (2) adding a metal source in portions for reaction; (3) adding a poor solvent to the reaction solution; (4) recrystallizing and drying; The specific operation for preparing the non-aqueous solvent solution of sulfonyl fluoride is as follows: displacing the reaction vessel with nitrogen, adding a non-aqueous solvent to the reaction vessel, controlling the temperature, and slowly introducing sulfonyl fluoride gas into the reaction vessel to obtain a non-aqueous solvent solution of sulfonyl fluoride; The overall reaction temperature of the preparation method of the fluorosulfonate is -30°C to 120°C; The temperature for preparing the non-aqueous solvent solution of sulfonyl fluoride is -30°C to 120°C; The metal type of the metal source is at least one of sodium, potassium, and lithium.

2. The method for preparing fluorosulfonate according to claim 1, characterized in that: The metal source is at least one of carbonate, bicarbonate, hydroxide, sulfate, phosphate, metal hydride, and elemental metal.

3. The method for preparing fluorosulfonate according to claim 1, characterized in that: The molar ratio of the sulfonyl fluoride to the metal source is 1:0.4 to 1.

5.

4. The method for preparing fluorosulfonate according to claim 1, characterized in that: The non-aqueous solvent is at least one of carboxylic acid esters, chain carbonates, cyclic carbonates, nitriles, halogenated alkanes, aromatic alkanes, and ethers; the carboxylic acid esters are ethyl acetate, methyl acetate, methyl formate, isopropyl acetate, and butyl acetate; the chain carbonates are at least one of ethyl methyl carbonate, dimethyl carbonate, and diethyl carbonate; the cyclic carbonates are ethylene carbonate, propylene carbonate, and vinylene carbonate; the nitriles are acetonitrile; the ethers are at least one of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, methyl tert-butyl ether, diisopropyl ether, ether, n-butyl ether, 1,4-dioxane ether, and tetrahydrofuran.

5. The method for preparing fluorosulfonate according to claim 1, characterized in that: The poor solvent is at least one of aliphatic hydrocarbons and aromatic hydrocarbons; the aliphatic hydrocarbons are at least one of dichloromethane, 1,2-dichloroethane, 1,2,3-trichloropropane, and 1,1,2,2-tetrachloroethane; the aromatic hydrocarbons are at least one of toluene, xylene, trimethylbenzene, chlorobenzene, dichlorobenzene, and trichlorobenzene.

6. The method for preparing fluorosulfonate according to claim 1, characterized in that: The mass ratio of the non-aqueous solvent to the poor solvent is 1:2 to 4.

7. An application of the method for preparing fluorosulfonate according to any one of claims 1 to 6, characterized in that: It includes the application of the preparation method of the fluorosulfonate in the preparation process of high-purity fluorosulfonate.