43results about "Lithium hexafluorophosphate" patented technology

This invention relates to the field of lithium battery technology and discloses a method for purifying lithium hexafluorophosphate by continuous flow crystallization. The method includes: (1) adding a first organic solvent to crude lithium hexafluorophosphate to dissolve it, preparing a saturated lithium hexafluorophosphate-organic solvent solution, filtering to remove insoluble matter, and obtaining a saturated lithium hexafluorophosphate solution; (2) feeding the saturated lithium hexafluorophosphate solution and the second organic solvent into a microchannel reactor for cooling using metering pumps, filtering the precipitated crystals, washing them with a cooled third organic solvent, and then vacuum drying. The lithium hexafluorophosphate precipitated by the method of this invention has high purity and stable quality, making it very suitable for industrial promotion and application.

The application provides a purification method of lithium fluoride, high-purity lithium fluoride, lithium hexafluorophosphate, an electrolyte and a device, and the purification method of the lithium fluoride comprises the following steps: performing water washing treatment on the lithium fluoride to be purified at 0-50 DEG C to obtain a mixture containing a first solid-phase product; performing ultrasonic treatment on the mixture at 20-25 kHz to obtain a second solid-phase product through filtration; performing fluorination reaction on the second solid-phase product with electronic-grade anhydrous hydrofluoric acid to obtain a third liquid-phase product; performing ion exchange on the third liquid-phase product by using a chelating resin at 0-80 DEG C, and then performing cooling evaporation crystallization, and obtaining a fourth solid-phase product through filtration; and performing cleaning treatment on the fourth solid-phase product by using inert gas at 150-250 DEG C to obtain high-purity lithium fluoride. The high-purity lithium fluoride obtained by the purification method has low content of lithium carbonate and other impurities, and is beneficial to improving the performance and stability of subsequent products.

In the crystallization system of the lithium hexafluorophosphate of the present invention, a first-stage crystallization kettle is connected to a lithium hexafluorophosphate mother liquor supply source through a lithium hexafluorophosphate mother liquor supply line; further connected to the lithium hexafluorophosphate mother liquor supply source through a mother liquor heat exchange line connected with a mother liquor heat exchanger; and further connected to a second-stage crystallization kettle through a first mother liquor delivery line configured to deliver lithium hexafluorophosphate mother liquor, a second-stage crystallization kettle is connected to a third-stage crystallization kettle through a second mother liquor delivery line configured to deliver lithium hexafluorophosphate mother liquor, a third-stage crystallization kettle is connected to a fourth-stage crystallization kettle through a crystalline particle delivery line configured to deliver small crystalline particles in the third-stage crystallization kettle; and further connected to a next process device through a first discharging line, and a fourth-stage crystallization kettle is connected to a next process device through a second discharging line. The crystallization system of lithium hexafluorophosphate of the present invention enables different crystallization stages to be carried out separately in different crystallization kettles, so as to realize continuous feeding and continuous discharging in the course of crystallization.

A method of producing lithium difluorophosphate, the method including: a step of obtaining a first raw material mixture by mixing lithium hexafluorophosphate, at least one selected from the group consisting of an oxide of phosphorus (A) and a lithium salt of a phosphoric acid (B), and a hydrocarbon solvent having from 6 to 12 carbon atoms; a step of obtaining a second raw material mixture by removing at least a part of the hydrocarbon solvent contained in the obtained first raw material mixture; and a step of producing a crude product containing lithium difluorophosphate by reacting the second raw material mixture.

A method for generating / synthesising a metal hexafluorophosphate is disclosed which comprises dissolving ammonium hexafluorophosphate in tetrahydrofuran (THF) solvent, and flowing the resulting dissol

Provided herein are compositions and methods of making compositions useful in the production of battery electrolyte precursors and battery electrolytes.

The invention belongs to the technical field of electrolyte material preparation, and particularly relates to a method for continuously preparing lithium hexafluorophosphate. The preparation method comprises the following steps: pulping and uniformly mixing excessive liquid PF5 and solid LiF in a pulping kettle, introducing the mixed material into a continuous reactor, controlling the temperature in the reactor to be greater than 18.95 DEG C and the pressure in the reactor to be greater than 3.39 MPa so that the PF5 is in a supercritical state, carrying out stirring reaction, decompressing the reaction material, feeding the reaction material into a spray drying tower, and carrying out solid-gas separation, the solid-phase product is lithium hexafluorophosphate, and the gas-phase component is PF5 which is compressed, condensed and recycled as a reaction raw material. According to the preparation method, the supercritical PF5 serves as a reaction raw material and a heat and mass transfer carrier at the same time, the reaction efficiency can be remarkably improved, other solvents or gas phase components are not introduced, and therefore efficient and high-quality continuous preparation of lithium hexafluorophosphate is achieved.

The invention relates to a preparation process of high-purity lithium hexafluorophosphate, which comprises the following specific steps: S1, quantitatively adding anhydrous hydrogen fluoride into a corresponding reaction kettle body, and controlling the environment temperature in the reaction kettle body at-50 DEG C to-20 DEG C through a temperature control device; s2, maintaining the pressure in the reaction kettle body at 0.1-0.5 MPa, dispersing and adding solid phosphorus pentachloride into the reaction kettle body through a corresponding feeding device, and enabling the solid phosphorus pentachloride to react with the anhydrous hydrogen fluoride in the step S1 at the temperature of-50 DEG C to-20 DEG C to obtain phosphorus pentafluoride and gaseous hydrogen chloride, the gaseous hydrogen chloride escapes from the reaction liquid and then is discharged for recovery or absorption treatment; and S3, dispersing and adding lithium fluoride into the reaction kettle body through the feeding device, and carrying out complexing reaction on the lithium fluoride and phosphorus pentafluoride in the anhydrous hydrogen fluoride to obtain lithium hexafluorophosphate. The reaction process is high in controllability, so that the high-purity lithium hexafluorophosphate product can be stably prepared.

The application discloses a preparation method of a flame-retardant lithium hexafluorophosphate organic solution, lithium hexafluorophosphate and a lithium battery. The preparation method comprises the following steps: mixing and reacting a lithium hexafluorophosphate salt and a benign flame-retardant solvent solution containing a lithium compound to obtain a lithium hexafluorophosphate solution with a flame-retardant effect, wherein the benign flame-retardant solvent comprises at least one of a phosphate ester and a phosphite ester; removing part of the solvent in the lithium hexafluorophosphate solution with the flame-retardant effect to obtain a concentrated solution; adding a carbonate to the concentrated solution to remove impurities; and then removing the carbonate to obtain the flame-retardant lithium hexafluorophosphate organic solution. The preparation method of the flame-retardant lithium hexafluorophosphate organic solution provided by the application does not require a strict anhydrous and anaerobic reaction environment, and the reaction speed is fast. The obtained flame-retardant lithium hexafluorophosphate organic solution does not need to go through processes such as drying, crystallization and dissolution, and can be directly used in a battery and has a certain flame-retardant property. The performance of the flame-retardant lithium hexafluorophosphate organic solution is similar to that of a commercial electrolyte.

Disclosed are a process and continuous system for producing LiPF6, and a prepared mixture crystal, composition, electrolyte solution and lithium ion battery containing LiPF6. During preparation, a first feed stream containing PF5 and a second feed stream containing LiF and HF are introduced into a first microchannel reactor, a gas part of a product in the first microchannel reactor is introduced into a second microchannel reactor to react with a third feed stream containing LiPF6, LiF and HF, and a liquid part of the product in the first microchannel reactor is subjected to crystallization and drying to obtain LiPF6. The LiPF6 has the advantages of a high purity, a uniform particle size, a high product quality stability, etc., and is suitable for use as a component of an electrolyte solution of a lithium ion battery.

In the crystallization system of the lithium hexafluorophosphate of the present invention, a first-stage crystallization kettle is connected to a lithium hexafluorophosphate mother liquor supply source through a lithium hexafluorophosphate mother liquor supply line; further connected to the lithium hexafluorophosphate mother liquor supply source through a mother liquor heat exchange line connected with a mother liquor heat exchanger; and further connected to a second-stage crystallization kettle through a first mother liquor delivery line configured to deliver lithium hexafluorophosphate mother liquor, a second-stage crystallization kettle is connected to a third-stage crystallization kettle through a second mother liquor delivery line configured to deliver lithium hexafluorophosphate mother liquor, a third-stage crystallization kettle is connected to a fourth-stage crystallization kettle through a crystalline particle delivery line configured to deliver small crystalline particles in the third-stage crystallization kettle; and further connected to a next process device through a first discharging line, and a fourth-stage crystallization kettle is connected to a next process device through a second discharging line. The crystallization system of lithium hexafluorophosphate of the present invention enables different crystallization stages to be carried out separately in different crystallization kettles, so as to realize continuous feeding and continuous discharging in the course of crystallization.

This invention discloses a method for preparing phosphorus pentafluoride and co-producing difluorochloromethane. The method includes the following steps: 1) vaporizing PCl and reacting it with CHF3 and Cl2 in a reaction tube equipped with a supported catalyst to undergo a fluorine-chlorine exchange reaction, yielding a mixed gas containing products such as PF5 and CHClF2; 2) fractionating the mixed gas in a distillation column, collecting the product PF5 and unreacted CHF3 mixture from the top of the condenser. This mixture is then directly reacted with a LiF carbonate solution to convert it into a high-value-added lithium hexafluorophosphate solution; another product, CHClF2, is collected from the body of the distillation column. This invention utilizes CHF3, a high-temperature-effect, long-life fluorine chemical byproduct, as a fluorine source and PCl3 as a phosphorus source. Through the fluorine-chlorine exchange reaction of CF3H, PCl3, and Cl2, it converts into high-value-added PF5 gas, which is further converted into LiPF6, while simultaneously co-producing CHClF2, thus realizing the resource utilization of fluorine and possessing significant economic and social benefits.

The invention relates to reaction equipment for preparing lithium hexafluorophosphate, which comprises a reaction kettle body, and a stirring shaft is rotatably mounted in the reaction kettle body; the feeding assembly comprises a set of discharging hoppers, and fixing plug bodies are installed on the bottom sides of the discharging hoppers in a liftable mode; the dispersing and discharging assembly comprises a set of arc-shaped guide grooves formed in the lower side of the fixed plug body, and the middles of the arc-shaped guide grooves protrude upwards; when the arc-shaped material guide groove rotates to pass through the bottom side of the fixed plug body, the driving mechanism drives the fixed plug body to leave the discharging opening of the discharging hopper; the heat exchange jacket is fixedly mounted on the outer side of the reaction kettle body, corresponding fixing grooves are concavely formed in the bottom side of the reaction kettle body at intervals, and corresponding heat exchange containers are respectively mounted in the fixing grooves in a swinging manner. According to the invention, the blanking uniformity of the material can be effectively and greatly improved, and the uniformity of the reaction temperature of the material in different reaction area ranges can be effectively and obviously improved.

The application discloses a continuous preparation process and device of liquid lithium hexafluorophosphate, and comprises the following operation steps: A10), continuously feeding lithium fluoride suspension to the top of a hexafluoride reaction plate tower; continuously feeding gaseous high-purity phosphorus pentafluoride to the bottom of the hexafluoride reaction plate tower; A20), carrying out reaction in the hexafluoride reaction plate tower, and feeding the reaction product from the bottom of the hexafluoride reaction tower into a bottom tank; A30), feeding the remaining reaction product output by a circulating heat exchanger into a liquid lithium hexafluorophosphate product extraction tank in one way and into a lithium fluoride suspension preparation kettle in the other way; and A40), connecting a filter to the product extraction end of the product extraction tank to remove the excessive solid-phase material after reaction, so as to obtain the liquid lithium hexafluorophosphate, the hydrogen chloride content of which is less than 25 ppm, and the hydrogen fluoride is not detected; the application has high continuous level and stability, does not need additional deacidification treatment, and has obviously higher output efficiency, and does not have the hidden troubles of shutdown maintenance due to problems such as blockage.

Disclosed are a manufacturing apparatus and manufacturing method for lithium hexafluorophosphate. The disclosed manufacturing apparatus for lithium hexafluorophosphate is configured to synthesize lithium hexafluorophosphate by reacting phosphorus pentafluoride with lithium fluoride and liquid anhydrous hydrogen fluoride, and comprises: a plurality of reactors connected to each other in series; and a plurality of recrystallizers connected to each other in series and installed downstream of the plurality of reactors so as to recrystallize the lithium hexafluorophosphate synthesized in the presence of phosphorus pentafluoride.

The crystallizer comprises a vertical container, the vertical container is installed on a fixing support through an elastic mechanism, and a vibration unit is further installed on the vertical container; a jacket matched with the vertical container in shape is arranged outside the vertical container, a refrigerant cavity is formed between the jacket and the vertical container, and the jacket is further provided with a refrigerant inlet and a refrigerant outlet which are communicated with the refrigerant cavity; the vertical container is provided with a mother liquor feed port, a nitrogen inlet, a mother liquor outlet and a discharge port; the discharge port is positioned at the bottom of the vertical container and is used for discharging crystallized materials, and meanwhile, a discharge valve for controlling the discharge port to be opened and closed is also arranged at the discharge port; the nitrogen inlet and the mother liquor outlet are positioned at the top of the vertical container, and a mother liquor insertion pipe downwards extending into the vertical container is also arranged at the mother liquor outlet. The device is simple in structure, easy to operate and capable of prohibiting external air from making contact with materials, controlling the amount of insoluble substances of lithium hexafluorophosphate and ensuring the stability of the quality of lithium hexafluorophosphate.

The application relates to a preparation method of a hexafluorophosphate, and belongs to the field of battery electrolytes. The preparation method comprises the following steps: carrying out an electrolysis reaction on anhydrous HF, phosphorus powder and an alkali metal fluoride salt to generate the hexafluorophosphate. The weak fluorine is electrolyzed from the anhydrous HF, and then the weak fluorine, the phosphorus powder and the alkali metal fluoride salt are reacted to directly synthesize the hexafluorophosphate by one-pot method, so that the yield is higher and the operation is simple. Compared with the reaction of fluorine gas and elemental phosphorus, the reaction of the weak fluorine obtained by the electrolysis method and the phosphorus powder is more moderate, easy to control and high in safety.

The present application relates to the technical field of chemical engineering, and provides a lithium hexafluorophosphate solution, and a preparation method therefor and a device therefor. The method comprises: performing a first contact reaction on a first phosphorus pentafluoride gas and a lithium fluoride solution to obtain a first reaction product; performing a second contact reaction on the first reaction product and a second phosphorus pentafluoride gas to obtain a second reaction product; and performing a third contact reaction on the second reaction product and a third phosphorus pentafluoride gas to obtain the lithium hexafluorophosphate solution. The phosphorus pentafluoride gas is step-fed, such that the feeding ratio of phosphorus pentafluoride to lithium fluoride can be dynamically and accurately controlled; and according to the reaction kinetic characteristics, the reaction process is optimized, and the chemical reaction speed between phosphorus pentafluoride and lithium fluoride is accelerated, so the lithium hexafluorophosphate solution can be efficiently synthesized in a short time, and the purity and the yield of the lithium hexafluorophosphate solution are improved.

The present invention belongs to the technical field of lithium-ion battery materials, and specifically relates to a method for synthesizing lithium hexafluorophosphate from lithium tripolyphosphate. The synthesis method comprises the following steps: uniformly mixing lithium tripolyphosphate and phosphorus pentoxide in an ether solvent to obtain a first mixture; introducing a mixed gas of hydrogen fluoride and nitrogen into the first mixture for a mixing reaction to obtain a second mixture; performing solid-liquid separation on the second mixture, and concentrating the filtrate after the solid-liquid separation under reduced pressure, recrystallizing, and drying under reduced pressure to obtain lithium hexafluorophosphate. The present invention uses lithium tripolyphosphate, phosphorus pentoxide, and hydrogen fluoride as raw materials, and adopts a method of uniformly introducing hydrogen fluoride gas into the reaction to directly react and synthesize lithium hexafluorophosphate in an ether solvent. The method has the advantages of mild reaction conditions, high reaction efficiency, high product purity, and high yield. The method solves the problems of high by-products and high costs in the industrial production of lithium hexafluorophosphate.

A method for recovering lithium salts from a lithium battery waste mass, comprising: (a) dissolving the lithium salts in the lithium battery waste mass in a weight of water equivalent to 100 to 0.1 times the weight of the lithium battery waste mass, either in a one-time process or in a continuous process; (b) evaporating the aqueous solution to dryness; and (c) agitating the dry residue with a solvent comprising water, a carbonate, or a mixture thereof.

The invention provides a lithium hexafluorophosphate continuous crystallization method and a lithium hexafluorophosphate crystal, and the lithium hexafluorophosphate continuous crystallization method comprises the following steps: mixing a hydrogen fluoride solution containing lithium hexafluorophosphate with an auxiliary agent gas, and carrying out continuous crystallization on the mixed material, carrying out multi-stage cooling on the mixed material in the continuous crystallization process; the auxiliary agent gas comprises one or more of boron trifluoride, silicon tetrafluoride and arsenic pentafluoride. By introducing auxiliary agent gas and combining gradient cooling, crystal ordered growth of lithium hexafluorophosphate can be promoted, and stable production of controllable continuous crystal of lithium hexafluorophosphate can be realized; and meanwhile, the adopted assistant gas does not influence the purity of the product, so that high-quality lithium hexafluorophosphate crystals can be continuously obtained, and the method is suitable for industrial production.

The present invention provides a method for producing phosphorus trifluoride and a method for producing phosphorus pentafluoride, which have high reaction efficiency, low reaction temperature and an excellent energy efficiency. The method for producing phosphorus trifluoride comprises: a step of introducing phosphorus trichloride and hydrogen fluoride into a first reactor; and a step of discharging phosphorus trifluoride from the first reactor, wherein the first reactor contains carbon material. The method for producing dichloro-phosphorus trifluoride comprises a step of introducing the phosphorus trifluoride obtained above and chlorine into a second reactor; and a step of discharging dichloro-phosphorus trifluoride from the second reactor. The method for producing phosphorus pentafluoride comprises: a step of introducing the dichloro-phosphorus trifluoride obtained above and hydrogen fluoride into a third reactor; and a step of discharging phosphorus pentafluoride from the third reactor. The method for producing lithium hexafluorophosphate comprises a step of introducing the phosphorus pentafluoride obtained above and lithium fluoride into a fourth reactor; and a step of discharging lithium hexafluorophosphate from the fourth reactor.

The application provides a preparation method and application of a sodium hexafluorophosphate concentrated solution and belongs to the field of batteries. Sodium halide and phosphorus pentachloride are reacted in a solvent (first reaction), a precursor solution generated in the reaction is reacted with hydrogen fluoride (second reaction), a sodium hexafluorophosphate solution is generated, and then degassing, filtration, concentration, dilution and resin deacidification are sequentially performed to obtain the sodium hexafluorophosphate concentrated solution. Then, impurities are removed by degassing, filtration, concentration, dilution and deacidification resin to obtain a final product. The sodium hexafluorophosphate concentrated solution product obtained by the application can be used as an electrolyte salt for a sodium ion battery electrolyte, and has the same or higher battery performance as that of a common sodium hexafluorophosphate crystal.

The application relates to a preparation method of lithium hexafluorophosphate and belongs to the field of preparation of lithium hexafluorophosphate. The preparation method comprises the following steps: carrying out high-pressure dry reaction of lithium fluoride solid and phosphorus pentafluoride gas, then continuously introducing the phosphorus pentafluoride gas to pressurize to 3.4 MPa or above and keep pressure, and cooling and decompressing to prepare lithium hexafluorophosphate; the pressure of the high pressure is 0.9-2.5 MPa, and the particle size of the lithium fluoride solid is 200-600 meshes. The reaction system is pressurized to 3.4 MPa or above and kept pressure, so that the phosphorus pentafluoride gas reaches a gas-liquid supercritical state, the fine lithium hexafluorophosphate crystal particles are rearranged and grown in the environment, and are approximately dissolved in the gas-liquid supercritical state of the phosphorus pentafluoride; in this way, the phosphorus pentafluoride can penetrate into the crystal grain and further react with the lithium fluoride, the residual lithium fluoride impurities are reduced, and the purity of the lithium hexafluorophosphate is improved.

The present application relates to the technical field of lithium hexafluorophosphate production, and discloses a production process of high-purity lithium hexafluorophosphate, which comprises the following process flow: dry base lithium fluoride is obtained by dehydrating and drying lithium fluoride; under the protection of nitrogen, hydrofluoric acid reacts with diaphosphorus pentoxide to generate lithium hexafluorophosphate; the obtained lithium hexafluorophosphate solution further reacts with sulfur trioxide at room temperature under the condition that the pressure is controlled to be 0.02 MPaG to generate phosphorus pentafluoride gas; the gas is introduced into a lithium fluoride mixed solvent to react with lithium fluoride, and the target crude product lithium hexafluorophosphate solution is obtained, and the reaction is ensured to be carried out under the protection of nitrogen; the lithium hexafluorophosphate solution is further purified, crystallized, crushed and dried, and the high-purity product lithium hexafluorophosphate crystal can be obtained, which can effectively save raw materials, improve the preparation efficiency of lithium hexafluorophosphate, adapt to the demand of mass production, improve the purity, reduce the requirement of preparation and processing procedures, and reduce the preparation cost.

The application belongs to the field of new energy, and discloses a preparation process of lithium hexafluorophosphate, which comprises the following steps: step 1: lithium fluoride and phosphorus pentachloride are reacted in an organic solvent to obtain a first mixture; and step 2: a fluorination reagent is added into the first mixture to obtain lithium hexafluorophosphate; the fluorination reagent is one or more of potassium fluoride, ammonium fluoride, calcium fluoride, potassium bifluoride and ammonium bifluoride. The process can obtain lithium hexafluorophosphate by a solvent method, and the yield is not less than 88%. Meanwhile, the application also discloses lithium hexafluorophosphate obtained based on the process.

Provided herein are compositions and methods of manufacturing compositions useful in producing battery electrolyte precursors and battery electrolytes.

The application discloses a lithium hexafluorophosphate tail gas comprehensive utilization system and method, which comprises a tail gas compressor, a tail gas pre-cooler, a gas-liquid separator, a 1# tower, a partial condenser, a 1# tower reflux tank, a reboiler, a 2# tower, an HCl absorption device and a drying device; after pre-cooling, the tail gas is separated by the gas-liquid separator, the liquid phase enters the 1# tower for separation, the anhydrous hydrogen fluoride product is obtained from the tower kettle, the gas phase at the top of the 1# tower is refluxed after partial condensation, the liquid is sent to the 1# tower and the 2# tower respectively, the gas phase obtained by the gas-liquid separator is sent into the 2# tower to contact with the liquid taken out from the top of the 1# tower to recover the remaining hydrogen fluoride, the recovered tail gas is introduced into the HCl absorption device to prepare hydrochloric acid, the nitrogen-containing tail gas is introduced into the drying device to obtain qualified nitrogen gas which is reused to the lithium hexafluorophosphate production section. Compared with the conventional pressurized rectification, the system has lower operating pressure, energy consumption and HF content in the terminal HCl tail gas, and a large amount of nitrogen gas is recycled and utilized, thereby reducing the production cost.

This invention provides a method for preparing a lithium hexafluorophosphate solution with reduced reaction byproduct content, belonging to the field of lithium-ion electrolyte manufacturing technology. It solves the problems of excessively high reaction byproduct content and difficulty in removing impurities in existing preparation methods. The invention includes the following steps: S1 organic solvent preparation; S2 purification of phosphorus pentafluoride gas preparation; S3 suspension mixture preparation; S4 initial stage lithium hexafluorophosphate solution preparation; S5 impurity adsorption; S6 preliminary filtration; S7 deacidification; S8 precision filtration. Through high-purity raw material preparation, strict reaction control, effective impurity removal steps, and the application of precision filtration technology, this invention successfully prepares a high-purity lithium hexafluorophosphate solution with low impurity content.

This invention provides a method for preparing lithium hexafluorophosphate. The method comprises the following steps: Step 1, adding molecular sieves to acetonitrile solvent, shaking well, and allowing to stand; Step 2, filtering the settled mixture to obtain treated acetonitrile solvent, and regenerating the filtered molecular sieve for reuse; Step 3, preparing a mixture of dried potassium hexafluorophosphate and the treated acetonitrile solvent in a container; Step 4, stirring the solution in the container, adding lithium hydride while stirring, and simultaneously introducing ammonia gas to catalyze the reaction until completion; Step 5, filtering the reactants from Step 4, performing vacuum distillation on the filtrate to recover some solvent, and then cooling to crystallize, obtaining a complex of lithium hexafluorophosphate and acetonitrile; Step 6, filtering the complex from Step 5 and vacuum drying to obtain lithium hexafluorophosphate. This method provides a green process for preparing lithium hexafluorophosphate that is safe, economical, and environmentally friendly.