121 results about "Lithium bicarbonate" patented technology

The invention discloses a preparation method of lithium trifluoromethanesulfinate, and belongs to the field of lithium ion battery materials. The preparation method of the lithium trifluoromethanesulfinate comprises the following steps: 1, mixing trifluoromethanesulfonyl chloride, lithium sulfite, lithium bicarbonate and a first solvent, and heating to react; 2, dissolving the concentrated crude product in a second solvent, and filtering and separating a lithium sulfate solid; and 3, concentrating the filtrate, adding a third solvent, uniformly stirring, filtering and separating the lithium chloride solid, and concentrating to obtain the lithium trifluoromethanesulfinate. According to the method for preparing the lithium trifluoromethanesulfinate, the yield can reach 94%, the operation is simple, byproducts are easy to separate, and the method is suitable for industrial production. In addition, the obtained by-product lithium sulfate can be used for preparing lithium sulfide, the by-product lithium chloride can be used for preparing solid electrolyte, and resource utilization is achieved.

The invention discloses a preparation method of battery-grade lithium hydroxide monohydrate, which comprises the following steps: causticizing a lithium sulfate concentrated solution, freezing and crystallizing to obtain a frozen solution, precisely filtering the frozen solution, filtering by adopting an alkali-resistant nanofiltration membrane, collecting a penetrating fluid, and when the permeability of the alkali-resistant nanofiltration membrane is reduced, filtering by adopting an alkali-resistant nanofiltration membrane to obtain the battery-grade lithium hydroxide monohydrate. The alkali-resistant nanofiltration membrane is cleaned by lithium bicarbonate thermal decomposition mother liquor of a lithium carbonate production line, and all collected penetrating fluid is subjected to evaporative crystallization and centrifugal drying to obtain the battery-grade lithium hydroxide monohydrate. By adopting a method of nanofiltration membrane impurity removal and primary evaporative crystallization, the nanofiltration membrane impurity removal is used for replacing the primary evaporative crystallization in the prior art, so that the energy consumption can be effectively reduced, the production cost is saved, the Si content of the nanofiltration solution is lower than 3ppm and lower than that of the primary evaporative crystallization heavy solution, and the method can be used for preparing high-quality battery-grade lithium carbonate. The Si content of the prepared lithium carbonate is lower than 20 ppm.

The invention discloses a method for converting lithium hydroxide into lithium carbonate. The method comprises the following steps: S1, preparing or taking a lithium hydroxide solution and a carbonate solution; s2, putting the lithium hydroxide solution and the carbonate solution into electrodialysis equipment, and carrying out electrodialysis treatment; and S3, after electrodialysis is finished, collecting a lithium carbonate solution, and sequentially carrying out lithium precipitation and solid-liquid separation on the lithium carbonate solution to obtain the battery-grade lithium carbonate. According to the method for converting lithium hydroxide into lithium carbonate disclosed by the invention, CO2 is replaced by carbonate, so that the generation of lithium bicarbonate is avoided, the lithium carbonate and the byproduct alkali liquor are directly obtained, the raw material source is wide, the preparation condition is mild, the production cost is greatly reduced, and the method has huge potential economic benefits.

The invention relates to the field of preparation of battery grade carbonic acid, and provides a method for preparing battery grade lithium carbonate by purifying crude lithium carbonate, the preparation method comprises the following steps: screening crude lithium carbonate from different sources, mixing lithium carbonate according to a certain solid-to-liquid ratio, and stirring to obtain dispersed slurry; cO2 gas is introduced into the obtained dispersed slurry for pre-hydrogenation treatment, and mixed slurry containing a lithium bicarbonate solution and solid lithium carbonate is obtained; adding a certain amount of lithium-containing reagent into the obtained mixed slurry, and heating the mixed slurry in a stirring state to obtain treated slurry; carrying out solid-liquid separation to obtain industrial-grade wet lithium carbonate and a lithium bicarbonate solution, and carrying out thermal decomposition on the lithium bicarbonate solution to obtain industrial-grade wet lithium carbonate; and carrying out size mixing, hydrogenation, thermal decomposition and solid-liquid separation on the two parts of industrial-grade wet lithium carbonate, and drying a filter cake to obtain the battery-grade lithium carbonate. The process flow is simple, the impurity removal efficiency is high, and the battery-grade lithium carbonate can be economically and efficiently prepared from the crude lithium carbonate raw materials with different sources and different qualities.

The utility model discloses a lithium hydroxide mother liquor precipitated lithium carbonate production system which comprises a front-stage impurity removal system, a reaction kettle, a centrifugal machine, a first-stage size mixing tank, a first-stage size washing kettle, a first-stage centrifugal machine, a second-stage size mixing tank, a second-stage size washing kettle, a second-stage centrifugal machine and a drying machine, a flowmeter and a regulating valve are arranged on the carbon dioxide inlet pipe, and an inlet pipe disc is arranged in the reaction kettle and is communicated with the carbon dioxide inlet pipe. Compared with the prior art, the pre-stage impurity removal system is used for removing impurities from the lithium hydroxide mother liquor, the proportion of carbon dioxide is reasonably controlled, excessive generation of lithium bicarbonate is avoided, and proper feeding amount, temperature and stirring speed are adopted, so that the reaction speed is controlled, a target lithium carbonate crystal form is obtained, impurity carrying is reduced, and the lithium carbonate quality is improved. The two-stage process operation of normal-temperature reaction and high-temperature pyrolysis is adopted, so that complete pyrolysis of lithium bicarbonate is ensured, the solubility of lithium carbonate is reduced, and the yield of lithium carbonate is increased.

The present invention relates to the technical field of retired battery recycling, and to a DRT-based method for efficiently recovering lithium from retired battery powder, and an application thereof. The method comprises: mixing retired battery powder, a carbon reducing agent and an A-site reaction material containing rare earth ions or alkaline earth ions, and carrying out reduction roasting to form reduced battery powder containing a perovskite-type oxide ABO3; mixing the reduced battery powder with water, and introducing carbon dioxide for carbonization leaching, to obtain a leachate material; carrying out solid-liquid separation on the leachate material, wherein the filtrate contains lithium bicarbonate; and carrying out impurity removal and pyrolysis on the filtrate to obtain battery-grade lithium carbonate. According to the present invention, synthesis of a perovskite-type oxide during reduction of battery powder is coupled and coordinated with carbonization leaching, so that carbon dioxide can be fixed, making the carbonization reaction more complete, and reducing the leaching of nickel, cobalt and manganese metals to obtain a pure lithium solution; subsequently, only simple impurity removal is required to obtain battery-grade lithium carbonate by pyrolysis.

The invention relates to the technical field of lithium salt preparation, and discloses a method for one-step preparation of low-sulfur low-sodium battery-grade lithium carbonate by a freezing semi-carbonization process, the process of preparing a finished liquid by concentrating a purified liquid in a traditional process is omitted, a carbonizer is added into the purified liquid, sodium sulfate is separated out after freezing, and lithium sulfate is converted into lithium bicarbonate, so that the lithium carbonate is prepared. The concentration of sulfate ions and sodium ions in the purification liquid is greatly reduced, then the nucleation rate is controlled by adjusting the concentration and dosage of the precipitator, the production of the low-sulfur and low-sodium battery-grade lithium carbonate is realized, the production process of the lithium carbonate is simplified, the energy consumption and production cost of the battery-grade lithium carbonate are reduced, and the production cost of the battery-grade lithium carbonate is reduced. And the low-sulfur and low-sodium battery-grade lithium carbonate is prepared.

The invention discloses a filtering device for lithium liquid extraction, and relates to the technical field of lithium liquid extraction. Comprising a tank body and a tank cover movably connected to the top of the tank body, the top of the tank cover and the left side of the tank body are fixedly connected with a discharging pipe and a feeding pipe respectively, a filter drum is arranged in the tank body, and the anti-blocking assembly is arranged in the tank body and used for reducing the blocking probability of the filter drum; the anti-blocking assembly comprises a flow guide baffle arranged on the inner wall of the left side of the tank body and corresponding to the feeding pipe, a spring is fixedly connected between the flow guide baffle and the side wall of the tank body, the right side of the flow guide baffle is fixedly connected with a cleaning arm, and the right side of the cleaning arm is fixedly connected with a cleaning brush; a connecting seat is arranged at the top of the filter cartridge; by avoiding direct impact on a specific area and continuous cleaning treatment, the smoothness of the filter cartridge is greatly guaranteed, meanwhile, lithium bicarbonate mother liquor entering the tank body also penetrates through the filter cartridge from different directions, the capturing and intercepting area of the filter cartridge is increased, and the capturing effect of the resin trapper is optimized.

The present invention discloses a method for recycling waste lithium battery materials, comprising the following steps: S1. Acid leaching the battery black powder; S2. Adding iron powder to remove copper; S3. Adding an oxidizing agent; S4. Adding extractant A to extract calcium and zinc to obtain a raffinate; S5. Adding extractant P507 to the raffinate obtained in S4 to extract cobalt and nickel to obtain a raffinate containing manganese, magnesium, and lithium; S6. Adding extractant Cy-272 to the raffinate obtained in S5 to extract nickel and magnesium to obtain a raffinate containing lithium; S7. Adding liquid caustic soda to the raffinate obtained in S6, filtering under pressure, concentrating, crystallizing, and centrifuging to separate anhydrous sodium sulfate and centrifugal mother liquor; cooling and filtering the centrifugal mother liquor, adding soda ash to the filtrate to obtain crude lithium carbonate, washing with water, pulping, injecting carbon dioxide to generate a lithium bicarbonate solution, and finally forming lithium carbonate. The present invention can balance the recovery rate and recovery purity of metallic lithium. When the recovery rate reaches over 90%, the purity can reach over 98%.

This invention provides a continuous production apparatus for preparing lithium bicarbonate using CO2, relating to the field of lithium carbonate preparation technology. It includes a feeding system, a mixing reaction unit, a clarification and separation unit, a frame, and a control system. The feeding system's organic phase feeding unit, aqueous phase feeding unit, and gas inlet unit enable precise proportioning and conveying of multiple materials. The preparation container of the mixing reaction unit is divided into multiple stirring chambers by annular baffles, each corresponding to a set of impellers. Optimized impeller parameters and axial spacing design, coupled with a microporous aeration device at the bottom of the preparation container, form a highly efficient composite flow field, enhancing three-phase mixing efficiency. The clarification and separation tank improves the gradient separation of the gas, liquid, and liquid phases through filter baffles. Through the coordinated operation of these systems, mixing reaction and product separation can be efficiently completed, achieving continuous production of lithium bicarbonate solution, ensuring product uniformity, and significantly improving CO2 utilization and gas-liquid mass transfer efficiency, which is of great significance for the industry's green and low-carbon transformation.

The utility model relates to the technical field of lithium carbonate preparation devices, in particular to a continuous carbonization and purification device for lithium carbonate. The utility model provides a lithium carbonate continuous carbonization and purification device which comprises three carbonization towers, a purification liquid storage tank, a pyrolysis tower, a pyrolysis heater, a thickener, a liquid storage tank and a centrifugal machine which are sequentially connected through pipelines, and the three carbonization towers are divided into a first-stage carbonization tower, a second-stage carbonization tower and a third-stage carbonization tower; the carbonization towers are sequentially arranged in series, and the step-by-step conveying of slurry is realized through a discharge pump arranged at the upper part of a pipeline; one side of the pyrolysis tower is connected with a recovery system for condensing and recovering carbon dioxide; the recovery system comprises an indirect condenser, a normal pressure buffer tank, a compressor unit, a pressurization buffer tank, a two-stage condenser, a water tank, a liquid storage tank and a vaporizer which are sequentially connected through pipelines. According to the carbonization and purification device, the carbonization tower, the pyrolysis tower and the recovery system are designed, so that the water dissolving and purification conversion operation between lithium carbonate and lithium bicarbonate is realized.

The application discloses a method for recycling battery-grade iron phosphate and lithium carbonate by using waste lithium iron phosphate battery materials. The method comprises the following steps: ①electrified crushing and disassembling the waste lithium iron phosphate battery materials, slurry, concentrated sulfuric acid leaching, pressure filtration, and obtaining an acid leaching solution; ②removing copper, aluminum and fluorine in the acid leaching solution in sequence; ③adjusting the iron-phosphorus ratio and pH value of the solution to precipitate iron phosphate, then aging the iron phosphate, two-stage pressure filtration and washing, drying and roasting to obtain battery-grade iron phosphate; ④removing iron from the solution after precipitating iron phosphate, pressure filtration, evaporation crystallization, adding sodium carbonate to precipitate lithium, and obtaining crude lithium carbonate, which is washed, slurried, carbonized, pressure filtered to prepare lithium bicarbonate filtrate, and then the lithium bicarbonate filtrate is refined, the resin is used to remove calcium and magnesium, thermal decomposition, centrifugal washing separation and drying to obtain battery-grade lithium carbonate. The application has high recovery rate of valuable elements, good impurity removal effect, can obtain battery-grade iron phosphate and lithium carbonate, and has high-efficiency and environmental protection process design, and is suitable for industrial application.

A method for the extraction of lithium from a lithium bearing material containing alpha spodumene, the method comprising the steps of: Converting at least a portion of the alpha spodumene present in the lithium bearing material to beta spodumene; Subjecting the lithium bearing material to a leaching process at an elevated pressure in the presence of potassium carbonate to produce a leaching solution containing lithium carbonate; Performing a carbonation process on the leaching solution to convert at least a portion of the lithium carbonate to lithium bicarbonate; Performing a solid-liquid separation process on the leaching solution to separate a leach residue from the leaching solution; Precipitating lithium carbonate from the leaching solution; and Separating precipitated lithium carbonate from the leaching solution.

The preparation method comprises the following steps: mixing a lithium source material, water, a first solvent and quaternary amine alkali, reacting the quaternary amine alkali with carbon dioxide in a reaction atmosphere containing carbon dioxide to generate HCO3 <->, reacting the HCO3 <-> with lithium ions in the lithium source material to generate lithium bicarbonate, and collecting a water phase after the reaction; decomposing lithium bicarbonate in the water phase to generate lithium carbonate, collecting a solid phase, and decomposing lithium carbonate in the solid phase to generate lithium oxide to obtain an intermediate; dissolving quaternary ammonium iodide in a second solvent, adding the intermediate, converting the lithium oxide into lithium hydroxide, carrying out ion exchange on the lithium hydroxide and the quaternary ammonium iodide to generate lithium iodide, and collecting a liquid phase; and collecting the lithium iodide in the liquid phase. According to the present invention, based on the characteristics of the specific quaternary ammonium base and the quaternary ammonium iodide salt, the Li in the lithium source material is selectively reinforced, carbonized and leached, the anion impurities in the lithium source material are removed, the anion exchange in the organic phase is achieved, and the high-purity anhydrous lithium iodide is prepared.

The present application relates to the field of battery raw material preparation, and discloses a lithium bicarbonate pyrolysis device for preparing lithium carbonate, comprising a reactor body, a stirring mechanism, a clamping mechanism, and a toggle mechanism. After the lithium bicarbonate solution is injected into the main reactor body, the stirring paddle stirs the solution at the bottom of the main reactor body. At the same time, since the plug in the clamping mechanism is inserted into the thread groove of the threaded rod, the clamping mechanism is driven to move upward by the threaded rod. At this time, the toggle mechanism moves upward together with the clamping mechanism. As the toggle mechanism moves upward, under the relative resistance of the solution, the hinge plate rotates downward, so that the heated solution located above the toggle mechanism and near the inner wall of the main reactor body flows toward the threaded rod below the toggle mechanism, thereby making the temperature of the solution in the main reactor body uniform, avoiding the gradient distribution of the solution with high edge temperature and low center temperature due to low heat exchange efficiency, which in turn causes the wall sticking phenomenon.

The invention relates to the technical field of lithium carbonate preparation, and provides a method for extracting battery-grade lithium carbonate from lithium precipitation mother liquor. The method comprises the following steps: adding lime milk into the lithium precipitation mother liquor to adjust the pH value, and then filtering to obtain a calcium and magnesium removal raw material; treating the calcium and magnesium removal raw material with calcium removal resin to obtain a refined raw material; performing three-stage extraction on the refined raw material and a lithium extraction extractant to obtain a lithium-loaded extractant; carrying out three-stage washing on the lithium-loaded extraction agent and pure water to obtain a clean lithium-loaded extraction agent; reacting the clean lithium-loaded extracting agent with pure water and carbon dioxide in a reverse extraction tower to obtain a lithium bicarbonate solution; treating the lithium bicarbonate solution through an oil removal resin column and a calcium and magnesium removal resin column in sequence to obtain a clean lithium bicarbonate solution; and pyrolyzing the lithium bicarbonate solution, and centrifugally separating to obtain a battery-grade lithium carbonate product. According to the method, efficient enrichment and purification of lithium are realized through multi-stage separation and conversion, and the strict requirement of battery-grade lithium carbonate on purity is finally met.

The invention discloses a method for preparing a silicon alloy and lithium carbonate by taking lithium ore as a raw material and application of the silicon alloy and the lithium carbonate. The method comprises the following steps: S1, carrying out high-temperature carbon thermal reduction smelting treatment on a mixed raw material, and cooling to obtain a silicon alloy and a lithium-rich product; s2, carrying out mixed acid roasting, leaching, impurity removal and lithium precipitation treatment on the lithium-rich product by using sulfuric acid, and carrying out centrifugal separation to obtain crude lithium carbonate; s3, the crude lithium carbonate is placed in deionized water, CO2 gas is introduced for a carbonization reaction, a lithium bicarbonate solution is obtained, then the lithium bicarbonate solution is subjected to thermal decomposition treatment, and final lithium carbonate is obtained. According to the method, the iron oxide with low cost is adopted as the raw material, the silicon alloy and the lithium-rich product are prepared through high-temperature reduction of the lithium ore, then the lithium element is extracted from the lithium-rich product through the wet process technology, and multi-component comprehensive utilization of lithium, silicon and aluminum resources in the lithium ore is achieved.

The invention belongs to the field of preparation of medical materials, and particularly relates to a preparation method of medical-grade high-purity lithium carbonate, which comprises the following steps: carrying out replacement reaction on metal lithium and deionized water to prepare a lithium hydroxide solution; introducing carbon dioxide gas into the lithium hydroxide solution, carrying out carbonization treatment, controlling the pH at the end point of the carbonization reaction to be 8-10.5, and then carrying out solid-liquid separation treatment to obtain a lithium bicarbonate solution; carrying out heat preservation treatment on the lithium bicarbonate solution at the temperature T and the pressure P, and separating to obtain pharmaceutical-grade high-purity lithium carbonate; the temperature T ranges from 90 DEG C to 98 DEG C, and the P ranges from 0.01 Mpa to 0.09 Mpa. According to the method, lithium carbonate is synthesized by utilizing a reaction mechanism of replacement-carbonization and thermal insulation transformation treatment, and on the basis, the combination of the pH value of carbonization and the temperature T and pressure P of thermal insulation treatment is further matched, so that the nucleation behavior of lithium carbonate can be accidentally controlled, the nucleation wrapping of impurities is reduced, and the purity of lithium carbonate is improved. Therefore, lithium carbonate which meets medical application requirements and has excellent particle size uniformity can be prepared with high direct yield based on a simple means.

The invention provides a device system and method for preparing high-purity lithium carbonate through micron / nano bubble deep carbonization-pyrolysis. The device system comprises a slurrying device, a first-stage deep carbonization device, a second-stage deep carbonization device, a pyrolysis device, a nano bubble generator, a first-stage micro bubble generator and a second-stage micro bubble generator. The slurrying device, the first-stage deep carbonization device, the second-stage deep carbonization device and the pyrolysis device are sequentially connected along the material flow direction; the first-stage deep carbonization device is bidirectionally connected with the first-stage microbubble generator; the secondary deep carbonization device is bidirectionally connected with the nano bubble generator; and the pyrolysis device is bidirectionally connected with the secondary microbubble generator. A micro-bubble generator or a nano-bubble generator is introduced into the first-stage deep carbonization device, the second-stage deep carbonization device and the pyrolysis device, so that the CO2 mass transfer rate is increased, the deep carbonization of lithium carbonate and the pyrolysis process of lithium bicarbonate are enhanced, and a uniform and fine high-purity lithium carbonate product can be efficiently prepared.

The invention discloses a method for removing impurities in industrial-grade lithium carbonate based on vegetable-tanned leather scraps, relating to the technical field of lithium carbonate purification, including: leather making, soaking leather scraps in a vegetable tanning agent for treatment, then washing and drying to obtain vegetable-tanned leather; preparing vegetable-tanned leather filter cloth; sizing, dispersing industrial-grade lithium carbonate in water to obtain a slurry; hydrogenation, introducing carbon dioxide into the slurry to obtain a hydrogenated feed liquid; filtering, filtering the hydrogenated feed liquid using a vegetable-tanned leather filter cloth; thermal decomposition, heating the lithium bicarbonate solution; solid-liquid separation, obtaining a mother liquor and battery-grade wet lithium carbonate; powdering, crushing the battery-grade wet lithium carbonate after drying to obtain battery-grade lithium carbonate dry powder. The present invention prepares vegetable-tanned leather by reacting leather scraps with glutaraldehyde and tannin, and then making a vegetable-tanned leather filter cloth for the impurity removal process of industrial-grade lithium carbonate, which can effectively filter and remove impurities, has good economy, and has high impurity removal efficiency.

This method (S05) for producing purified lithium carbonate comprises: a slurrying step (S51) in which water is added to lithium carbonate that contains 400 mass ppm or more of calcium so as to produce a lithium carbonate slurry; a bicarbonation step (S52) in which a CO2 gas is blown into the lithium carbonate slurry so as to produce lithium bicarbonate, thereby obtaining a lithium bicarbonate solution; a first solid-liquid separation step (S53) in which calcium carbonate suspended in the lithium bicarbonate solution is separated; a purified lithium carbonate crystallization step (S54) in which the lithium bicarbonate solution after the removal of the calcium carbonate is warmed so as to decompose the lithium bicarbonate, thereby precipitating purified lithium carbonate; a second solid-liquid separation step (S55) in which the precipitated purified lithium carbonate is separated from the mother liquid; and a mother liquid returning step (S56) in which the mother liquid obtained in the second solid-liquid separation step (S55) is returned to the slurrying step (S51).

Provided is a method for producing a lithium carbonate from a basic lithium- and aluminum-containing waste liquid generated during a positive electrode material production process, the method comprising the steps of: (a) filtering the waste liquid to remove metal solids; (b) injecting carbon dioxide into the waste liquid removed of the metal solids, thereby converting a lithium hydroxide into a lithium bicarbonate; (c) adding an anion exchange resin to the lithium bicarbonate-containing waste liquid to convert a lithium sulfate into a lithium hydroxide; (d) injecting carbon dioxide into the lithium hydroxide-containing waste liquid to convert the lithium hydroxide into a lithium carbonate; and (e) concentrating the lithium carbonate-containing waste liquid using an evaporator and then recovering a solid lithium carbonate.

The present application relates to the technical field of separation and purification of inorganic materials, and specifically discloses a method for preparing lithium carbonate from lithium ore. The preparation method comprises: pre-treating the lithium ore, adding water, stirring and leaching, and filtering to obtain a leachate; adding a complexing agent to the leachate, mixing, filtering, collecting a filter cake, adding deionized water and a complexing agent to the filter cake, and simultaneously introducing carbon dioxide to obtain a solution containing lithium bicarbonate; mixing with a cationic chelating resin, reacting, filtering, and collecting a filtrate to obtain a first mixed solution; mixing the first mixed solution with an anion exchange resin, reacting, filtering, and collecting a filtrate to obtain a second mixed solution; adding sodium carbonate to the second mixed solution, mixing, filtering, and obtaining a crude lithium carbonate product; repeatedly washing with water, filtering, and drying to obtain lithium carbonate. The method for preparing lithium carbonate from lithium ore of the present application has the advantages of reducing impurities and improving the purity of lithium carbonate through the synergistic effect between the steps.

The utility model discloses a carbonization device. The carbonization device comprises a carbonization tower, a cooling mechanism and a turbidity meter, the carbonization tower is provided with a return port and a discharge port which are communicated with the interior of the carbonization tower; the cooling mechanism comprises a cooler and a material circulating pump, the discharging end of the cooler is communicated with the material returning opening of the carbonization tower, and the material circulating pump is connected between the discharging opening of the carbonization tower and the feeding end of the cooler, so that materials can circularly flow in the cooler and the carbonization tower; and the turbidity meter is arranged at the discharge hole of the carbonization tower. A material containing lithium carbonate is carbonized in the carbonization tower to form lithium bicarbonate, and in the carbonization process, the material circularly flows in the cooler and the carbonization tower through the material circulating pump, so that the material is cooled, and the carbonization effect of the lithium carbonate is improved. Meanwhile, the turbidity meter can be used for detecting the turbidity of the material at the discharge hole of the carbonization tower, so that the carbonization degree can be judged according to the turbidity, the carbonization degree is ensured to meet the requirement, and the subsequent purification effect is ensured. The utility model further discloses a purification system.

The invention provides a method for preparing lithium carbonate by using lithium iron phosphate waste batteries, which comprises the following steps: adding inorganic acid and hydrogen peroxide into dispersion liquid containing lithium iron phosphate battery powder, reacting the dispersion liquid under the conditions that the pH value is 2.1-2.5 and heating is performed, and performing suction filtration and washing to obtain first filtrate; adding a composite impurity removal agent containing sodium hydroxide and calcium hydroxide into the first filtrate under the hot bath condition, reacting the first filtrate under the condition that the pH value is 10-10.5, and performing suction filtration and washing to obtain second filtrate; performing extraction and carbon dioxide back extraction on the second filtrate to obtain back extraction liquid containing lithium bicarbonate; and pyrolyzing lithium bicarbonate in the back extraction liquid to obtain lithium carbonate.

According to the invention there is provided a process comprising admixing lithium iron phosphate (LFP), an oxidizing agent, carbon dioxide, and water; separating an aqueous solution that includes lithium carbonate and / or lithium bicarbonate from the admixture.

This invention discloses a method for the green recycling of all components of waste lithium iron phosphate batteries, belonging to the field of new energy resource recycling technology. The invention involves crushing and slicing the waste batteries in an aqueous solution continuously purged with carbon dioxide, prioritizing the non-destructive separation of the negative electrode graphite; the metal sheets are sorted to obtain the iron shell, separator, copper foil, and aluminum foil containing powder; a gas-liquid-solid Fenton reaction system is constructed using carbon dioxide, hydrogen peroxide, and lithium iron phosphate, simultaneously degrading PVDF and electrolyte, and performing dealuminization and lithium impregnation under mild, acid- and alkali-free conditions; the slurry is subjected to two-stage sieving to obtain delithiated iron phosphate powder, and lithium bicarbonate solution is heated and decomposed to obtain lithium carbonate, achieving a closed-loop carbon dioxide recycling process. This invention solves the problems of high energy consumption from high-temperature roasting, significant pollution from strong acids and alkalis, difficulty in separating mixed components, and damage to graphite and metal foil in traditional recycling methods. It achieves high-purity recycling of all components—negative electrode graphite, copper foil, aluminum foil, iron phosphate, and lithium—with low energy consumption and no high-salt wastewater, making it suitable for large-scale application.

The invention discloses a method for preparing battery-grade lithium fluoride by using crude lithium carbonate, which comprises the following steps: S1, adding ultrapure water into a reactor filled with crude lithium carbonate, stirring, then adding an impurity removal agent, and continuously stirring to obtain crude lithium carbonate slurry; s2, introducing CO2 into the crude lithium carbonate slurry for carbonization, and filtering to obtain a lithium bicarbonate solution; s3, adding a complexing agent into the lithium bicarbonate solution, heating, cooling, filtering and washing to obtain a wet filter cake; s4, adding ultrapure water into the reactor filled with the wet filter cake, and stirring to prepare lithium carbonate slurry; and S5, introducing the lithium carbonate slurry and hydrofluoric acid into a reaction kettle in a manner of simultaneously dropwise adding to react to obtain a wet lithium fluoride product, and performing suction filtration and drying on the wet product to obtain the battery-grade lithium fluoride. The preparation method provided by the invention is suitable for preparing crude lithium carbonate from various raw materials; the preparation process is simple and low in cost; and the quality of the obtained product meets the industrial standard requirements of battery-grade lithium fluoride YS / T 661-2016.

The utility model discloses improved lithium bicarbonate pyrolysis equipment, which belongs to the technical field of lithium recovery, and adopts the technical scheme that the improved lithium bicarbonate pyrolysis equipment comprises a support frame, a pyrolysis tank and a negative pressure tank are arranged on the support frame, the pyrolysis tank is connected with the negative pressure tank through a pipeline, the pyrolysis tank is communicated with a heat supply pipe and a feeding pipe, and the negative pressure tank is communicated with the heat supply pipe. The pyrolysis tank comprises a flow guide part and a standing part, a spiral track is arranged on the inner surface of the flow guide part, the standing part comprises a rotating rod, a connecting frame is fixedly connected to the end of the rotating rod, a standing disc is slidably connected to the end of the connecting frame, a plurality of liquid leakage holes are formed in the standing disc in a penetrating mode, and the liquid leakage holes are communicated with the rotating rod. A supporting rod used for shielding the liquid leakage hole is arranged at the position, corresponding to the liquid leakage hole, of the connecting frame, a plug is installed at the bottom of the standing part, and a sampling hole is formed in the plug. The equipment can improve the lithium precipitation rate, sample and detect at any time, and accelerate the lithium precipitation rate.

The present invention discloses a nickel-cobalt-manganese ternary cathode material, a preparation method thereof and an application thereof, belonging to the technical field of lithium ion battery materials. The preparation method of the material comprises the following steps: dissolving nickel salts, cobalt salts and manganese salts in a solvent, adding a mixed solution composed of an organic carboxylic acid and ammonia water to obtain a solution B; preparing a solution C containing lithium bicarbonate and ammonium bicarbonate; mixing the solution B and the solution C and then carrying out a hydrothermal reaction to obtain a precursor of the ternary cathode material, and roasting the precursor to obtain the nickel-cobalt-manganese ternary cathode material. During the above hydrothermal reaction process, the pyrolysis of bicarbonate and the precipitation of four metal ions of nickel, cobalt, manganese and lithium occur simultaneously in the whole system, so that nickel, cobalt, manganese and lithium are uniformly distributed in the prepared precursor, and the migration paths of various elements in the subsequent calcination process of the precursor with uniform distribution of each component are short, which is beneficial to the formation of a lamellar phase and the integrity of the material lattice, thereby playing a role in improving the electrochemical performance of the material.