A preparation method of bis(trifluoromethanesulfonyl)imide salt

Abstract

The present invention provides a preparation method of bis(trifluoromethanesulfonyl)imide salt, belonging to the chemical engineering field. Using NH2M, where M = Li, Na, K, Rb or Cs, HSO2X and CX4, where X is F, Cl, Br or I, and anhydrous hydrogen fluoride as synthetic raw materials to prepare bis(trifluoromethanesulfonyl)imide salt. The preparation method has simple synthesis, convenient operation, low energy consumption and low labor consumption, which is beneficial to industrial production.

Description

Technical Field

[0001] The present invention relates to the chemical industry field, and particularly to a preparation method of bis(trifluoromethanesulfonyl)imide salt with the molecular formula MN(CF3SO2)2, where M is lithium, sodium, potassium, rubidium or cesium. Background Art

[0002] Bis(trifluoromethanesulfonyl)imide salt has structural stability. In organic solvents, the cation shows active free property, and it has excellent physical and electrochemical properties. Especially lithium bis(trifluoromethanesulfonyl)imide and sodium bis(trifluoromethanesulfonyl)imide have gradually become important additives or electrolytes for lithium-ion or sodium-ion batteries.

[0003] In the prior art, reports related to the preparation of bis(trifluoromethanesulfonyl)imide salt mainly involve Chinese patent applications with application numbers 201610324110.2 and 202010932449.7.

[0004] Among them, the Chinese patent application with application number 201610324110.2 discloses a preparation method of lithium bis(trifluoromethanesulfonyl)imide. The steps of the preparation method are as follows: benzylamine is dissolved in an organic solvent and undergoes a sulfonamide reaction with trifluoromethanesulfonyl chloride or trifluoromethanesulfonyl fluoride to obtain benzyl bis(trifluoromethylsulfonyl)amine, which is then reduced to bis(trifluoromethylsulfonyl)amine. Then, under anhydrous solvent conditions, it undergoes ion exchange with resin lithium to obtain the final product lithium bis(trifluoromethanesulfonyl)imide salt. Among them, the raw material trifluoromethanesulfonyl is not easily obtained. Literature mentions that generally electrolysis with fluorine is used, the electrolysis energy consumption is extremely high, and the fluorine-containing electrolysis process is very dangerous and the process is complex.

[0005] The Chinese patent application with application number 202010932449.7 discloses a preparation method of lithium bis(trifluoromethanesulfonyl)imide. The steps of the preparation method are as follows: trifluoromethanesulfonamide is neutralized with an alkali metal lithium salt to obtain lithium trifluoromethanesulfonamide salt, and then it reacts with trifluoromethanesulfonyl chloride under the catalytic action of lithium salts such as lithium carbonate, saccharin lithium, and lithium oxalate to obtain lithium bis(trifluoromethanesulfonyl)imide. In this invention patent application, the raw materials also involve trifluoromethanesulfonyl, the raw material cost is relatively high, and impurities such as oxalic acid are introduced in the process, resulting in an increase in production cost during the subsequent purification process.

[0006] In summary, in the prior art, there are various defects in the reports related to the preparation of bis(trifluoromethanesulfonyl)imide salt: the reaction raw materials are not easily obtained, dangerous, high in energy consumption, increasing the difficulty of purification, high in cost, etc. Summary of the Invention

[0007] The object of the present invention is to provide a preparation method of bis(trifluoromethanesulfonyl)imide salt, the molecular formula of the bis(trifluoromethanesulfonyl)imide salt is MN(CF3SO2)2, and M is an alkali metal Li, Na, K, Rb or Cs. The preparation method has simple process, low energy consumption, easily available raw materials, and higher safety during the preparation process.

[0008] The steps of the preparation method of the present invention are as follows:

[0009] S1: Preparation of bis(trifluorohalomethanesulfonyl)imide salt:

[0010] (1) Add a carbonate solvent, NH2M, HSO2X, and CX4 into a reaction kettle, and mix to obtain a mixture;

[0011] HSO2X is a sulfonyl halide hydride, and CX4 is a carbon tetrahalide, where X is a halogen F, Cl, Br or I;

[0012] The molar ratio of NH2M to HSO2X is 1:2 - 10;

[0013] The molar ratio of NH2M to CX4 is 1:2.2 - 12;

[0014] (2) Stir evenly in the reaction kettle, control the reaction temperature at -10°C to 70°C, and continuously reflux for 5H to 20H;

[0015] (3) After the reaction is completed, cool to room temperature and filter to remove impurities to obtain a bis(trifluorohalomethanesulfonyl)imide salt solution.

[0016] The chemical reaction equation is as follows:

[0017] NH2M + 2HSO2X + 2CX4 = MN(CX3SO2)2 + 4HX

[0018] S2: Preparation of bis(trifluoromethanesulfonyl)imide salt:

[0019] (1) Adjust the temperature of the bis(trifluorohalomethanesulfonyl)imide salt solution to -20°C to 15°C, add a supported catalyst, and the addition amount is 5 - 10% of the mass percentage of the bis(trifluorohalomethanesulfonyl)imide salt solution, and dropwise add anhydrous hydrogen fluoride, and the dropping rate is 10L / min to 50L / min;

[0020] The molar ratio of anhydrous hydrogen fluoride to bis(trifluorohalomethanesulfonyl)imide salt is 6 - 12:1;

[0021] When X in CX4 is F, this step of dropwise adding anhydrous hydrogen fluoride is omitted;

[0022] The chemical reaction equation is as follows:

[0023] MN(CX3SO2)2 + 6HF = MN(CF3SO2)2 + 6HX

[0024] (2) After the reaction is completed, the supported catalyst is removed by filtration, the solution is heated and concentrated for crystallization. After crystallization is completed, the solution is removed to obtain the crude reaction product, which is dried under vacuum to obtain the bis(trifluoromethanesulfonyl)imide salt.

[0025] Preferably, the carbonate used in the carbonate solution in step (1) of S1 is dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, ethylene carbonate or a mixed solution of the above carbonates in a certain proportion;

[0026] Preferably, the molar ratio of NH2M, HSO2X, and CX4 in (1) of step S1 is 1:2:2.2 to 1:2.5:6;

[0027] Preferably, before adding anhydrous hydrogen fluoride dropwise in (1) of step S2, the solution temperature is adjusted to -5°C to 5°C;

[0028] Preferably, the dropping rate of anhydrous hydrogen fluoride in (1) of step S2 is 20 L / min to 30 L / min;

[0029] Preferably, the molar ratio of anhydrous hydrogen fluoride to bis(trifluoromethanesulfonyl)imide in (1) of step S2 is 7 to 8:1.

[0030] Preferably, the supported catalyst is a fluorination catalyst of organometallic antimony supported on tourmaline ceramic balls, and its preparation method is as follows:

[0031] S1: Taking 5 - 12 parts by mass of antimony pentachloride and dissolving it in 100 - 150 parts by mass of N,N-dimethylformamide (DMF) to prepare a metal ion solution;

[0032] S2: Taking 2 - 5 parts by mass of 3,4,5,6-tetrafluorophthalic acid, 13 - 26 parts by mass of 4-vinyl-1,2-benzenedicarboxylic acid, 120 - 200 parts by mass of N,N-dimethylformamide, and 3 - 6 parts by mass of hydrochloric acid with a mass percentage content of 20 - 30%, adding them to a stirring kettle, stirring at 70 - 80°C for 50 - 100 min, then pouring the metal ion solution prepared in S1 into the ligand solution for mixing, and then adding it to a hydrothermal reaction kettle, reacting at 70 - 85°C for 1 - 4 hours to obtain a vinyl fluorinated organometallic intermediate;

[0033] S3: Under a nitrogen atmosphere, add 50 - 100 parts of tourmaline ceramic balls treated with mercapto - silane, 0.05 - 0.4 parts of 1 - vinyl - 3 - ethylimidazolium hexafluorophosphate (1034364 - 43 - 6), 7 - 11 parts of potassium hydroxide, and 600 - 800 parts of N,N - dimethylformamide into a reaction kettle. Stir at 70 - 80 °C for 40 - 70 minutes, then add the vinyl - containing fluorinated organometallic intermediate prepared in S2, stir at 70 - 80 °C for 40 - 60 hours, filter, and then dry under vacuum at 50 - 80 °C for 12 - 36 hours to obtain a fluorination catalyst with organometallic antimony supported on tourmaline ceramic balls.

[0034] Preferably, the preparation method of the tourmaline ceramic balls treated with mercapto - silane is as follows:

[0035] By mass fraction, take 150 - 240 parts of tourmaline ceramic balls, dissolve them in 1000 - 1500 parts of water, add 4 - 7 parts of mercapto - silane, react at 30 - 45 °C for 40 - 150 minutes, filter, and dry to obtain tourmaline ceramic balls treated with mercapto - silane.

[0036] Reaction mechanism for the preparation of the supported catalyst:

[0037] The catalyst used: The mercapto group of the tourmaline ceramic balls treated with mercapto - silane first undergoes an addition reaction with 1 - vinyl - 3 - ethylimidazolium hexafluorophosphate, and then undergoes a mercapto - vinyl addition reaction with the vinyl - containing fluorinated organometallic intermediate to obtain a fluorination catalyst with organometallic antimony supported on tourmaline ceramic balls.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] (1) The technological process adopted in this method is simple, avoiding cumbersome operations, shortening the reaction time, and reducing the reaction temperature, thus improving the production efficiency.

[0040] (2) The fluorination catalyst with organometallic antimony supported on tourmaline ceramic balls can be easily separated. At the same time, its tetrafluoroalkyl group has good compatibility with the reactants, and the structure is conducive to the enrichment of heptafluoroisobutenyl methyl ether on the catalyst surface and in micropores, which can effectively improve the catalytic effect and shorten the reaction time.

[0041] The beneficial effects of the present invention are:

[0042] The present invention provides a preparation method of bis(trifluoromethanesulfonyl)imide salt. Compared with the prior art, the present invention provides different raw material routes and synthesis methods, with a simpler process, lower energy consumption, safer preparation process, easily available raw materials, and high product purity.

[0043] The preparation method of the present invention has simple equipment and low production cost. The product, bis(trifluoromethanesulfonyl)imide salt, especially the lithium salt and sodium salt, can be used as the electrolyte or additive of lithium or sodium ion secondary batteries, which is beneficial to the industrial development of new energy lithium or sodium ion batteries. Description of the Drawings

[0044] Figure 1 It is the process flow chart of the preparation method of the present invention. Detailed Embodiments

[0045] To better understand the above technical solution, the embodiments of the present invention further elaborate on the present invention by listing the preparation of bis(trifluoromethanesulfonyl)imide salt.

[0046] The following specific embodiments are detailed descriptions of the technical solution of this application. It should be understood that the embodiments of this application and the specific features in the embodiments are detailed descriptions of the technical solution of this application, rather than limitations on the technical solution of this application. Without conflict, the embodiments of this application and the compounds and technical features in the embodiments can be combined with each other. It should be understood that the term "and / or" used herein includes any and all combinations of one or more of the associated listed items.

[0047] The following provides a more detailed description of this application through examples. These examples are only descriptions of the best implementation modes of this application and do not limit the scope of this application in any way.

[0048] Example 1

[0049] Add 2000 g of dimethyl carbonate to the reaction kettle, then add 200 g of NH2Rb and 331 g of HSO2F and stir evenly, and then slowly add 2559.6 g of CI4 to obtain a mixture.

[0050] The molar ratio of NH2Rb, HSO2F to CI4 is 1:2:2.5.

[0051] Stir the reaction kettle evenly and heat it to 35 °C for continuous reflux reaction for 5 h.

[0052] After the reaction is completed, cool it to room temperature and filter to remove impurities to obtain a solution of RbN(CI3SO2)2.

[0053] Cool the bis(trifluoromethanesulfonyl)imide rubidium solution to 10 °C, add a supported catalyst, and the addition amount is 5% of the mass percentage of the bis(trifluoromethanesulfonyl)imide salt solution, and dropwise add 236.5 g of anhydrous hydrogen fluoride at a dropping rate of 10 L / min.

[0054] The molar ratio of anhydrous hydrogen fluoride to NH2Rb is 6:1.

[0055] After the reaction is completed, the supported catalyst is removed by filtration, the solution is heated and concentrated for crystallization. After crystallization is completed, the solution is removed to obtain the crude reaction product, and 655.4 g of rubidium bis(trifluoromethanesulfonyl)imide is obtained after vacuum drying. The yield based on NH2Rb is 91%.

[0056] The supported catalyst is a fluorination catalyst of organometallic antimony supported on tourmaline ceramic balls, and its preparation method is as follows:

[0057] S1: Dissolve 5 g of antimony pentachloride in 100 g of N,N-dimethylformamide (DMF) to prepare a metal ion solution;

[0058] S2: Add 2 g of 3,4,5,6-tetrafluorophthalic acid, 13 g of 4-vinyl-1,2-benzenedicarboxylic acid, 120 g of N,N-dimethylformamide, and 3 g of 20% by mass hydrochloric acid to a stirring kettle, stir at 70 °C for 50 min, then pour the metal ion solution prepared in S1 into the ligand solution for mixing, and then add it to a hydrothermal reaction kettle, and react at 70 °C for 1 hour to obtain a vinyl fluorinated organometallic intermediate;

[0059] S3: Under a nitrogen atmosphere, add 50 g of mercapto-silane-treated tourmaline ceramic balls, 0.05 g of 1-vinyl-3-ethylimidazolium hexafluorophosphate (1034364-43-6), 7 g of potassium hydroxide, and 600 g of N,N-dimethylformamide to the reaction kettle, stir at 70 °C for 40 minutes, then add the vinyl fluorinated organometallic intermediate prepared in S2, stir at 70 °C for 40 hours, filter, and then vacuum dry at 50 °C for 12 hours to obtain a fluorination catalyst of organometallic antimony supported on tourmaline ceramic balls.

[0060] The preparation method of the mercapto-silane-treated tourmaline ceramic balls is as follows:

[0061] Take 150 g of tourmaline ceramic balls and dissolve them in 1000 g of water, add 4 g of mercapto-silane, react at 30 °C for 40 minutes, filter, and dry to obtain mercapto-silane-treated tourmaline ceramic balls.

[0062] Example 2

[0063] Add 1800 g of diethyl carbonate to the reaction kettle, then add 50 g of NH2Li and 548.6 g of HSO2Cl and stir evenly, then slowly add 1008.7 g of CCl4, and mix to obtain a mixture;

[0064] The molar ratio of NH2Li, HSO2Cl to CCl4 is 1:2.5:3;

[0065] The reaction kettle is stirred evenly and heated to 45 °C for continuous reflux reaction for 7 h;

[0066] After the reaction is completed, it is cooled to room temperature and filtered to remove impurities to obtain a solution of LiN(CCl3SO2)2;

[0067] The lithium bis(trichloromethanesulfonyl)imide solution is cooled to 0 °C, and a supported catalyst is added. The addition amount is 6% of the mass percentage of the lithium bis(trichloromethanesulfonyl)imide salt solution. 349.3 g of anhydrous hydrogen fluoride is added dropwise at a dropping rate of 20 L / min;

[0068] The molar ratio of anhydrous hydrogen fluoride to LiNH2 is 8:1;

[0069] After the reaction is completed, the supported catalyst is removed by filtration. The solution is heated, concentrated and crystallized. After crystallization is completed, the solution is removed to obtain a crude reaction product. After vacuum drying, 563.78 g of lithium bis(trifluoromethanesulfonyl)imide is obtained, and the yield based on LiNH2 is 90%.

[0070] The supported catalyst is a fluorination catalyst of organometallic antimony supported on tourmaline ceramic balls, and its preparation method is as follows:

[0071] S1: Dissolve 7 g of antimony pentachloride in 110 g of N,N-dimethylformamide (DMF) to prepare a metal ion solution;

[0072] S2: Add 3 g of 3,4,5,6-tetrafluorophthalic acid, 18 g of 4-vinyl-1,2-benzenedicarboxylic acid, 150 g of N,N-dimethylformamide, and 4 g of 25% by mass hydrochloric acid to a stirring kettle, stir at 75 °C for 60 min, then pour the metal ion solution prepared in S1 into the ligand solution for mixing, and then add it to a hydrothermal reaction kettle and react at 75 °C for 2 hours to obtain a vinyl fluorinated organometallic intermediate;

[0073] S3: Under a nitrogen atmosphere, add 60 g of mercapto-silane-treated tourmaline ceramic balls, 0.2 g of 1-vinyl-3-ethylimidazolium hexafluorophosphate (1034364-43-6), 8 g of potassium hydroxide, 650 g of N,N-dimethylformamide to the reaction kettle, stir at 75 °C for 50 min, then add the vinyl fluorinated organometallic intermediate prepared in S2, stir at 75 °C for 45 hours, filter, and then vacuum dry at 60 °C for 20 hours to obtain a fluorination catalyst of organometallic antimony supported on tourmaline ceramic balls.

[0074] The preparation method of the mercapto-silane-treated tourmaline ceramic balls is as follows:

[0075] Take 180 g of tourmaline ceramic balls and dissolve them in 1200 g of water, add 5 g of mercapto-silane, react at 35 °C for 80 min, filter, and dry to obtain mercapto-silane-treated tourmaline ceramic balls.

[0076] Example 3

[0077] Add 1300 g of the mixed solution of ethyl methyl carbonate and ethylene carbonate to the reaction kettle, then add 80 g of NH2K and 632.3 g of HSO2Br and stir evenly, and then slowly add 512 g of CF4 to obtain a mixture;

[0078] The molar ratio of NH2K, HSO2Br to CF4 is 1:3:4;

[0079] Stir the reaction kettle evenly, heat it to 65 °C and keep it refluxing for 15 h;

[0080] After the reaction is completed, cool it to room temperature and filter to remove impurities to obtain a solution of KN(CF3SO2)2;

[0081] Heat the solution for concentration and crystallization. After crystallization is completed, remove the solution to obtain the crude reaction product. After vacuum drying, 426.9 g of potassium bis(trifluoromethanesulfonyl)imide is obtained, and the yield based on NH2K is 92%.

[0082] Example 4

[0083] Add 1900 g of the mixed solution of diethyl carbonate and dimethyl carbonate to the reaction kettle, then add 250 g of NH2Cs and 564.1 g of HSO2F and stir evenly, and then slowly add 3340.5 g of CBr4 to obtain a mixture;

[0084] The molar ratio of NH2Cs, HSO2F to CBr4 is 1:4:6;

[0085] Stir the reaction kettle evenly, heat it to 70 °C and keep it refluxing for 19 h;

[0086] After the reaction is completed, cool it to room temperature and filter to remove impurities to obtain a solution of CsN(CBr3SO2)2;

[0087] Cool the cesium bis(tribromomethanesulfonyl)imide solution to -5 °C, add a supported catalyst, and the addition amount is 8% of the mass percentage of the bis(trihalomethanesulfonyl)imide salt solution, and add 335.8 g of anhydrous hydrogen fluoride dropwise at a dropping rate of 43 L / min;

[0088] The molar ratio of anhydrous hydrogen fluoride to NH2Cs is 10:1;

[0089] After the reaction is completed, filter to remove the supported catalyst, heat the solution for concentration and crystallization. After crystallization is completed, remove the solution to obtain the crude reaction product. After vacuum drying, 617.0 g of cesium bis(trifluoromethanesulfonyl)imide is obtained, and the yield based on NH2Cs is 89%.

[0090] The supported catalyst is a fluorination catalyst of tourmaline ceramic balls loaded with organometallic antimony, and its preparation method is as follows:

[0091] S1: Dissolve 10 g of antimony pentachloride in 140 g of N,N-dimethylformamide (DMF) to prepare a metal ion solution;

[0092] S2: Add 4 g of 3,4,5,6-tetrafluorophthalic acid, 22 g of 4-vinyl-1,2-benzenedicarboxylic acid, 180 g of N,N-dimethylformamide, and 5 g of 25% hydrochloric acid by mass percentage to a stirring kettle, stir at 75 °C for 90 min, then pour the metal ion solution prepared in S1 into the ligand solution for mixing, and then add it to a hydrothermal reaction kettle, react at 80 °C for 3 hours to obtain a vinyl fluorine-containing organometallic intermediate;

[0093] S3: Under a nitrogen atmosphere, add 90 g of mercapto-silane-treated tourmaline ceramic balls, 0.3 g of 1-vinyl-3-ethylimidazolium hexafluorophosphate (1034364-43-6), 10 g of potassium hydroxide, and 750 g of N,N-dimethylformamide to a reaction kettle, stir at 75 °C for 60 minutes, then add the vinyl fluorine-containing organometallic intermediate prepared in S2, stir at 75 °C for 55 hours, filter, and then vacuum dry at 70 °C for 30 hours to obtain a fluorination catalyst with organometallic antimony supported on tourmaline ceramic balls.

[0094] The preparation method of the mercapto-silane-treated tourmaline ceramic balls is as follows:

[0095] Dissolve 220 g of tourmaline ceramic balls in 1400 g of water, add 6 g of mercapto-silane, react at 40 °C for 120 minutes, filter, and dry to obtain mercapto-silane-treated tourmaline ceramic balls.

[0096] Example 5

[0097] Add 2500 g of ethyl methyl carbonate solution to a reaction kettle, then add 100 g of NH2Na and 2460 g of HSO2I and stir evenly, then slowly add 2764 g of CCl4, and mix to obtain a mixture;

[0098] The molar ratio of NH2Na, HSO2I to CCl4 is 1:5:7;

[0099] Stir the reaction kettle evenly, heat to 60 °C and continue to reflux and react for 17H;

[0100] After the reaction is completed, cool to room temperature and filter to remove impurities to obtain a NaN(CCl3SO2)2 solution;

[0101] Cool the sodium bis(trichloromethanesulfonyl)imide solution to -15 °C, add a supported catalyst, and the addition amount is 5% of the mass percentage of the sodium bis(trichloromethanesulfonyl)imide solution, and dropwise add 564 g of anhydrous hydrogen fluoride, and the dropping rate is 35 L / min;

[0102] The molar ratio of anhydrous hydrogen fluoride to NaNH₂ is 11:1;

[0103] After the reaction is completed, the supported catalyst is removed by filtration, and the solution is heated and concentrated to obtain 3000 g of a solution containing the product. The concentration of the solution is measured to be 25% by the weight loss method, and it is calculated that 750 g of sodium bis(trifluoromethanesulfonyl)imide is synthesized in total.

[0104] The supported catalyst is a fluorination catalyst of organometallic antimony supported on tourmaline ceramic balls, and its preparation method is as follows:

[0105] S1: Dissolve 5 g of antimony pentachloride in 100 g of N,N-dimethylformamide (DMF) to prepare a metal ion solution;

[0106] S2: Add 2 g of 3,4,5,6-tetrafluorophthalic acid, 13 g of 4-vinyl-1,2-benzenedicarboxylic acid, 120 g of N,N-dimethylformamide, and 3 g of 20% hydrochloric acid by mass percentage to a stirring kettle, stir at 70 °C for 50 min, then pour the metal ion solution prepared in S1 into the ligand solution for mixing, and then add it to a hydrothermal reaction kettle and react at 70 °C for 1 hour to obtain a vinyl fluorinated organometallic intermediate;

[0107] S3: Under a nitrogen atmosphere, add 50 g of tourmaline ceramic balls treated with mercapto silane, 0.05 g of 1-vinyl-3-ethylimidazolium hexafluorophosphate (1034364-43-6), 7 g of potassium hydroxide, 600 g of N,N-dimethylformamide to the reaction kettle, stir at 70 °C for 40 minutes, then add the vinyl fluorinated organometallic intermediate prepared in S2, stir at 70 °C for 40 hours, filter, and then vacuum dry at 50 °C for 12 hours to obtain a fluorination catalyst of organometallic antimony supported on tourmaline ceramic balls.

[0108] The technical solutions in the embodiments of the present application have the advantages of simple process, low energy consumption, low cost, etc., and are easy to be implemented industrially.

[0109] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the appended claims are intended to be construed to include the preferred embodiments as well as all changes and modifications falling within the scope of the present invention.

[0110] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims

1. A preparation method of bis(trifluoromethanesulfonyl)imide salt, the molecular formula of the bis(trifluoromethanesulfonyl)imide salt is MN(CF3SO2)2, where M is an alkali metal Li, Na, K, Rb or Cs, through the following steps: S1: Preparation of bis(trifluoromethanesulfonyl)imide salt: (1) Add a carbonate solvent, NH2M, HSO2X, and CX4 into a reaction kettle, and mix to obtain a mixture; X in HSO2X and CX4 is a halogen F, Cl, Br or I; (2) Stir evenly in the reaction kettle, control the reaction temperature at -10°C to 70°C and continuously reflux for 5H to 20H; (3) After the reaction is completed, cool to room temperature and filter to remove impurities to obtain a bis(trifluoromethanesulfonyl)imide salt solution; S2: Preparation of bis(trifluoromethanesulfonyl)imide salt: (1) Adjust the temperature of the bis(trifluoromethanesulfonyl)imide salt solution to -20°C to 15°C, add a supported catalyst, and the addition amount is 5-10% of the mass percentage of the bis(trifluoromethanesulfonyl)imide salt solution, and dropwise add anhydrous hydrogen fluoride, and the dropping rate is 10L / min to 50L / min; (2) After the reaction is completed, filter to remove the supported catalyst, heat and concentrate the solution to crystallize, and after crystallization is completed, remove the solution to obtain a crude reaction product, and obtain bis(trifluoromethanesulfonyl)imide salt after vacuum drying.

2. The preparation method of a bis(trifluoromethanesulfonyl)imide salt according to claim 1, characterized in that: The carbonate solvent is dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate, ethylene carbonate or a mixed solution of the above carbonates in a certain proportion.

3. The preparation method of a bis(trifluoromethanesulfonyl)imide salt according to claim 1, characterized in that: The molar ratio of NH2M, HSO2X, and CX4 is 1:2:2.2 to 1:10:

12.

4. The preparation method of a bis(trifluoromethanesulfonyl)imide salt according to claim 1, wherein: The reaction in step (2) of S1 is carried out at -10°C to 70°C, and the reaction time is 5h to 20h.

5. The preparation method of a bis(trifluoromethanesulfonyl)imide salt as claimed in claim 1, characterized in that: The molar ratio of anhydrous hydrogen fluoride to NH2M in step (1) of S2 is 6 to 12:

1.

6. The preparation method of a bis(trifluoromethanesulfonyl)imide salt according to claim 1, wherein: The reaction temperature in step (1) of S2 is -20°C to 15°C, and the dropping rate of anhydrous hydrogen fluoride is 10 to 50L / min.

7. The preparation method of a bis(trifluoromethanesulfonyl)imide salt as described in claim 1, characterized in that: In step (2) of S2, the reaction solution can be directly heated and concentrated to a bis(trifluoromethanesulfonyl)imide salt solution with the required concentration to prepare a bis(trifluoromethanesulfonyl)imide salt liquid.

8. The preparation method of a bis(trifluoromethanesulfonyl)imide salt according to claim 1, characterized in that: The supported catalyst is a fluorination catalyst of tourmaline ceramic balls loaded with organometallic antimony, and its preparation method is: S1: Take 5-12 parts by mass of antimony pentachloride and dissolve it in 100-150 parts by mass of N,N-dimethylformamide (DMF) to prepare a metal ion solution; S2: According to the mass fraction, add 2-5 parts of 3,4,5,6-tetrafluorophthalic acid, 13-26 parts of 4-vinyl-1,2-benzenedicarboxylic acid, 120-200 parts of N,N-dimethylformamide, and 3-6 parts of 20-30% by mass percentage of hydrochloric acid into a stirring kettle, stir at 70-80°C for 50-100 min, then pour the metal ion solution prepared in S1 into the ligand solution for mixing, and then add it to a hydrothermal reaction kettle, and react at 70-85°C for 1-4 hours to obtain a vinyl-containing fluorinated organometallic intermediate; S3: Under a nitrogen atmosphere, add 50 - 100 parts of mercapto - silane - treated tourmaline ceramic balls, 0.05 - 0.4 parts of 1 - vinyl - 3 - ethylimidazolium hexafluorophosphate, 7 - 11 parts of potassium hydroxide, and 600 - 800 parts of N,N - dimethylformamide into a reaction kettle. Stir at 70 - 80 °C for 40 - 70 minutes, then add the vinyl - containing fluorine - organic metal intermediate prepared in S2, stir at 70 - 80 °C for 40 - 60 hours, filter, and then vacuum - dry at 50 - 80 °C for 12 - 36 hours to obtain a fluorination catalyst with organometallic antimony supported on tourmaline ceramic balls.

9. The preparation method of a bis(trifluoromethanesulfonyl)imide salt according to claim 8, characterized in that: The preparation method of the mercapto - silane - treated tourmaline ceramic balls is as follows: According to the mass parts, take 150 - 240 parts of tourmaline ceramic balls and dissolve them in 1000 - 1500 parts of water, add 4 - 7 parts of mercapto - silane, react at 30 - 45 °C for 40 - 150 minutes, filter, and dry to obtain mercapto - silane - treated tourmaline ceramic balls.

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