CN-121990950-A - Lithium trifluoromethylsulfinate and preparation method and application thereof

Abstract

The invention belongs to the technical field of organofluorine industry, and particularly relates to lithium trifluoromethylsulfinate, a preparation method and application thereof. The preparation method of the lithium trifluoromethylsulfinate is characterized by comprising the following steps of firstly mixing and dissolving sodium sulfite, lithium carbonate, tetrabutylammonium decatungstate and sodium ascorbate in a solvent, deoxidizing an obtained system, then introducing trifluoromethane gas, controlling the reaction pressure to be 0.4-1.0 MPa, starting a visible light source, controlling the wavelength of the light source to be 400-430 nm, carrying out illumination reaction to obtain a reaction solution, and finally carrying out post-treatment on the reaction solution to obtain the lithium trifluoromethylsulfinate. The preparation method provided by the invention is efficient, low in cost and environment-friendly, and the prepared lithium trifluoromethylsulfinate is high in purity and yield and can be applied to the fields of lithium ion battery lithium supplement, energy storage equipment or pharmaceutical chemicals.

Inventors

• XIA KAI
• WANG ZHE
• DOU ZHIQUN

Assignees

• 淄博飞源化工有限公司

Dates

Publication Date

20260508

Application Date

20260410

Claims (10)

1. 1. The preparation method of the lithium trifluoromethylsulfinate is characterized by comprising the following steps of firstly mixing and dissolving sodium sulfite, lithium carbonate, tetrabutylammonium decatungstate and sodium ascorbate in a solvent, deoxidizing an obtained system, then introducing trifluoromethane gas, controlling the reaction pressure to be 0.4-1.0 MPa, starting a visible light source, controlling the wavelength of the light source to be 400-430 nm, carrying out illumination reaction to obtain a reaction solution, and finally carrying out post-treatment on the reaction solution to obtain the lithium trifluoromethylsulfinate.
2. 2. The preparation method of the lithium trifluoromethylsulfinate is characterized by comprising the steps of firstly mixing and dissolving sodium sulfite, lithium carbonate, tetrabutylammonium decatungstate and sodium ascorbate in a solvent, wherein the solvent is acetonitrile and water, and the volume ratio of acetonitrile to water is 4:1-1:1.
3. 3. The method for preparing the lithium trifluoromethylsulfinate according to claim 1, wherein the reaction is carried out at room temperature for 6-12 hours.
4. 4. The method for preparing the lithium trifluoromethylsulfinate according to claim 1, wherein the post-treatment comprises the specific steps of evaporating and concentrating the reaction solution to be viscous, adding absolute ethyl alcohol for dissolving, filtering, concentrating the filtrate again, adding a mixed solvent for recrystallization, cooling, precipitating white crystals, filtering and collecting the white crystals, and drying.
5. 5. The method for preparing lithium trifluoromethylsulfinate according to claim 4, wherein the mixed solvent is acetonitrile and toluene, and the volume ratio of acetonitrile to toluene is 3:1-1:1.
6. 6. The method for preparing lithium trifluoromethylsulfinate according to claim 4, wherein the drying is vacuum drying, and the drying temperature is 100-120 ℃.
7. 7. The method for preparing lithium trifluoromethylsulfinate according to claim 1, wherein the molar ratio of sodium sulfite, lithium carbonate, tetrabutylammonium decatungstate and sodium ascorbate is 1.0:0.55-0.7:0.01-0.03:1.0-2.0.
8. 8. The method for preparing lithium trifluoromethylsulfinate according to claim 1, wherein the molar ratio of the introduced amount of trifluoromethane gas to sodium sulfite is 1:1.0-2.0.
9. 9. A lithium trifluoromethylsulfinate, characterized in that it is prepared by the process for preparing a lithium trifluoromethylsulfinate according to any one of claims 1 to 8.
10. 10. The method of claim 9, wherein the lithium trifluoromethylsulfinate is used in lithium ion battery lithium supplement, energy storage device or pharmaceutical chemical field.

Description

Lithium trifluoromethylsulfinate and preparation method and application thereof Technical Field The invention belongs to the technical field of organofluorine industry, and particularly relates to lithium trifluoromethylsulfinate, a preparation method and application thereof. Background Lithium triflate (CF 3SO2 Li) is a fluorine-containing lithium salt with unique physical and chemical properties, has the strong electron-withdrawing property of trifluoromethyl and the ion conductivity of lithium sulfinate in the molecular structure, and has wide application prospect in the fields of new energy, pharmaceutical chemistry, material science and the like by virtue of excellent electrochemical stability, good solubility and compatibility with various materials, and particularly has irreplaceable important value in the field of lithium ion batteries. In the field of lithium ion batteries, the trifluoromethyl sulfinic acid lithium is taken as a novel lithium carrier molecule, the accurate supplement of lithium ions can be realized, the capacity attenuation problem of the lithium battery caused by active lithium ion loss is effectively solved, the service time of the battery is greatly prolonged, meanwhile, the lithium battery is stable in air and relatively low in synthesis cost, is perfectly matched with graphite, silicon carbon negative electrodes and various positive electrode materials, can be widely applied to scenes such as electric automobiles and energy storage power stations, and provides key technical support for the upgrading development of the lithium battery industry. At present, the preparation method of the lithium trifluoromethylsulfinate is mainly prepared by reacting a pre-functionalized high-activity fluorine-containing reagent with sulfite. CN120817877a discloses a method for preparing trifluoromethyl sulfonyl chloride, which uses trifluoromethyl sulfonyl chloride and lithium sulfite as raw materials, and carries out nucleophilic substitution reaction in organic solvent, and sulfur atoms in sulfonyl chloride are attacked by sulfite anions to generate lithium trifluoromethyl sulfinate, and then the target product is obtained through steps of filtering, concentrating, recrystallizing and the like. The reaction path of the method is relatively direct, and has certain convenience in small-scale preparation in a laboratory, but is limited by the characteristics of raw materials, so that large-scale mass production is difficult to realize. CN120794890A is a conversion method of trifluoromethyl sulfinate, sodium trifluoromethyl sulfinate is used as a starting material, alkylation reaction is carried out with benzyl halide to generate S-benzyl trifluoromethyl sulfinate, hydrogenation reduction reaction is carried out in the presence of a catalyst to remove benzyl, and lithium salt replacement is carried out to finally obtain lithium trifluoromethyl sulfinate. Therefore, the prior art has high production cost, relies on pre-functionalized high-activity fluorine-containing reagents such as trifluoromethyl sulfonyl chloride or sodium trifluoromethyl sulfinate, has complex synthesis process and harsh reaction conditions, leads to high market price and directly pushes up the preparation cost of lithium trifluoromethyl sulfinate. Secondly, the reaction flow is complex and the yield is low, particularly the trifluoromethyl sulfinate conversion method is the most typical, which involves multi-step reactions such as alkylation, hydrogenation reduction, lithium salt replacement and the like, each step of reaction needs to strictly control the reaction conditions, and separate separation and purification operations need to be carried out. Finally, the environmental burden is heavy, a large amount of organic waste liquid is generated in each step of separation and purification process, and if the waste liquid is improperly treated, the waste liquid can pollute the soil, water and other environments. Disclosure of Invention The invention aims to overcome the technical defects of high production cost, complex reaction flow, low yield and heavy environmental burden in the preparation of the lithium trifluoromethylsulfinate in the prior art, provides the lithium trifluoromethylsulfinate, the preparation method and the application thereof, the preparation method is efficient, low in cost and environment-friendly, and the prepared lithium trifluoromethylsulfinate is high in purity and yield, and can be applied to effectively supplementing active lithium ions lost by a battery, obviously recovering the battery capacity and prolonging the cycle life of the battery. The preparation method of the lithium trifluoromethylsulfinate comprises the steps of firstly mixing sodium sulfite, lithium carbonate, tetrabutylammonium decatungstate and sodium ascorbate to dissolve in a solvent to obtain a uniform and stable reaction system, carrying out deoxidization treatment on the system (preferably adopting high-purity nitrogen to repl