483results about "Lithium halides" patented technology

This invention discloses a method for leaching lithium iron phosphate mixed powder with iron salts and recovering all components, belonging to the field of battery recycling. The invention uses an iron salt solution to leach the mixed powder, obtaining a lithium-containing leachate and leaching residue. Ferrous ions in the leachate are regenerated into ferric iron through acidification and oxidation, and recycled for leaching the next batch of mixed powder. After reaching a preset number of cycles, the leachate is used for re-leaching multiple batches of leaching residue to improve the lithium leaching rate. Ultimately, a enriched solution containing Li, Fe, Cu, and Al and graphite-containing iron phosphate residue are obtained. Copper is recovered from the enriched solution through iron powder replacement, and a high-purity lithium chloride solution is obtained through extraction and separation, while ferric chloride (recycled) and aluminum chloride crystals are also recovered. The leaching residue is treated with hydrochloric acid to obtain regenerated graphite, and the pH is adjusted with alkali to obtain high-purity iron phosphate. This method achieves full component recovery under mild conditions, reducing separation steps and chemical consumption through a "leaching-regeneration-leaching" cycle mechanism, thus achieving both environmental and economic benefits.

The present application discloses a method for recovering battery-grade iron phosphate and lithium salts from lithium iron phosphate waste materials and its application, comprising the following steps: S100, dissolving the lithium iron phosphate waste materials with a phosphoric acid solution, filtering to obtain a waste material dissolution solution; S200, adding an acid solution and an oxidant to the waste material dissolution solution to obtain a crystallization stock solution; S300, diluting the crystallization stock solution with water until its pH value is 1.0 to 1.5, and performing high-temperature crystallization to obtain hydrated iron phosphate and a lithium-containing filtrate; S400, roasting the hydrated iron phosphate to obtain battery-grade iron phosphate; S500, removing water from the lithium-containing filtrate to obtain solution a, circulating solution a to dissolve the lithium iron phosphate waste materials, and concentrating to obtain lithium salts. The present application uses a phosphoric acid solution as the leaching solvent, does not require the use of an alkali solution subsequently and can be leached cyclically, improving the economic benefits while enabling the efficient recovery of all elements of Li, Fe, and P, and also capable of obtaining a battery-grade iron phosphate product with an iron-to-phosphorus ratio meeting the requirements.

The invention belongs to the technical field of lithium ion battery positive electrode materials, and provides a plasma-assisted in-situ constructed lithium ion conductor coated high-nickel ternary positive electrode material as well as a preparation method and application thereof. Oxygen plasma active groups are formed through high-pressure ionization of oxygen, and the generated active groups interact with gas generated by thermal decomposition of an added solid source; the residual alkali on the surface of the high-nickel ternary positive electrode can be consumed, and a thin, continuous and compact lithium ion conductor coating layer with good conductivity is formed on the surface of the high-nickel ternary positive electrode material in situ, so that the development of the high-nickel ternary positive electrode material of the lithium ion battery is promoted. The high-nickel ternary positive electrode material prepared by the invention shows high specific capacity, excellent cycling stability, rate capability and first charge-discharge efficiency. Meanwhile, the preparation method provided by the invention is simple, rapid, efficient, convenient and low in cost, the residual alkali on the surface of the high-nickel ternary positive electrode material can be effectively removed, and the structural stability of the high-nickel ternary positive electrode material is improved.

The invention belongs to the technical field of hybrid supercapacitors, and discloses a coal-based hard carbon negative electrode material with high slope lithium storage capacity and a preparation method and application of the coal-based hard carbon negative electrode material. Washing the pulverized coal subjected to impurity removal with ultrapure water until the pH value is neutral, and then drying; pre-oxidizing the pulverized coal in an air atmosphere at 280-320 DEG C for 110-130 minutes, switching a gas atmosphere into a protective atmosphere after the pre-oxidation is finished, continuously heating, carbonizing at 1180-1220 DEG C for 110-130 minutes, washing with an acid solution to be neutral after the carbonization is finished, and drying to obtain a carbon material subjected to heat treatment; impregnating the surface of the carbon material subjected to heat treatment with lithium fluoride; and carrying out heat treatment on the material A at 280-320 DEG C in a protective atmosphere for 280-320 minutes to obtain the coal-based hard carbon negative electrode material with high slope lithium storage capacity. The power and capacity performance of the hybrid super capacitor can be improved, the intrinsic safety of the device can be further improved, and the hybrid super capacitor has great practical significance.

The invention provides lithium brine thallium removal equipment and a magnetic MOFs thallium removal agent preparation process thereof. The water pollution treatment device comprises a bottom plate, a tank body, a top cover, a mounting plate, a positioning frame, a driving mechanism and a discharging mechanism, the tank body is mounted on the upper surface of the bottom plate, the top cover is mounted on the upper surface of the tank body through bolts, the mounting plate is mounted on the upper surface of the top cover, and the positioning frame is mounted on the upper surface of the mounting plate. In the rotating process of the rotating drum, the rotating drum is automatically driven by the guide wheel to automatically ascend along with the thickness of the auxiliary plate, and when the guide wheel rotates to the vertical plane of the auxiliary plate, the guide wheel automatically falls to control the rotating drum to reset, so that the rotating drum can vertically move in the rotating process; in addition, small-amplitude vibration can be formed, so that the Fe3O4-coated UiO-66-NH2 nanoparticles are firstly treated into a liquid state and then are injected into the lithium leaching solution, and the concentration in the leaching solution can be ensured to be more uniform.

The invention belongs to the technical field of inorganic salt chemical industry. The invention provides a method for preparing anhydrous lithium chloride by using salt lake brine with low magnesium-lithium ratio, which comprises the following steps: pumping clear salt lake brine with low magnesium-lithium ratio into a plate-and-frame filter press for filtration, and sequentially performing microporous filtration and ultrafiltration on filtrate to obtain primary refined brine; filtering the primary refined brine through a nanofiltration membrane device to obtain secondary refined brine; allowing the secondary refined brine to pass through chelating resin to obtain magnesium-removed brine; mixing the magnesium-removed brine with an alkali solution, adjusting the pH value of the mixed solution, and pumping the mixed solution into a continuous extraction device for solvent extraction to obtain a lithium chloride solution; and evaporating and drying the lithium chloride solution in sequence to obtain an anhydrous lithium chloride product. The anhydrous lithium chloride product is prepared by adopting a nanofiltration membrane separation and solvent extraction combined process, the recovery rate of lithium ions is higher than 80%, the fresh water consumption of 1 ton of lithium chloride product is less than 50 cubic meters, the production cost is low, the chemical units are few, and the automation degree is high.

The utility model discloses a lithium chloride mother liquor refining system for extracting lithium from a salt lake, which comprises a sodium sulfate dissolving kettle, a primary crystallization reaction kettle, a primary plate-and-frame filter press, a secondary crystallization reaction kettle, a secondary plate-and-frame filter press, a microporous filter element filter, nano-filtration equipment, a resin adsorption filter, a filter residue stirring kettle and a precipitation residue filter press, the sodium sulfate dissolving kettle is communicated with the interior of the primary crystallization reaction kettle through a sodium sulfate solution pipeline, the filter residue stirring kettle is communicated with slag outlets of the primary plate-and-frame filter press and the secondary plate-and-frame filter press, and the filter residue stirring kettle is communicated with the interior of the sodium sulfate dissolving kettle through a precipitation slag filter press. Compared with the prior art, the lithium chloride mother liquor is used as a raw material, insoluble impurities, soluble ions and organic matters in the raw material are removed through deep crystallization and impurity removal, solid-liquid separation of precipitates is easy, and meanwhile, entrainment of lithium ions in the precipitates is reduced, so that lithium chloride refined liquor is obtained, and 99.9% battery-grade lithium carbonate can be directly prepared in a lithium precipitation process.

The invention relates to a preparation method of a membrane material, in particular to a preparation method of a nanofiltration membrane applied to magnesium-lithium separation. According to the preparation method of the polyamide nanofiltration membrane capable of avoiding the acyl chloride hydrolysis influence, provided by the invention, the acyl chloride hydrolysis is avoided by mainly utilizing interfacial polymerization of gas-phase amine and acyl chloride, and the application potential of the membrane can be well improved by adopting the hollow fiber as the support body.

Methods and systems for direct-write liquid phase epitaxy of ionic materials are provided for herein, and relate to the manufacture of metal halide optics among other applications. Deposition of the ionic material is induced by mixing at least two fluids of differing composition, wherein the solubility limit of the ionic material in the mixed solution is lower than predicted from a linear combination of the original fluids. This deposition process is spatially controlled using a printhead, enabling localized material deposition and the ability to create arbitrary geometries in turn. In some cases, at least one of the fluids is saturated with the ionic material and surrounds the substrate upon which deposition occurs.

The invention belongs to the technical field of sodium-ion battery positive electrode material preparation, and particularly discloses a double-modified sodium-ion battery layered oxide positive electrode material and a preparation method thereof, and the preparation method comprises the following steps: S1, synthesizing a P2-type sodium-ion battery nickel-manganese-based layered oxide by using a high-temperature solid-phase method; s2, uniformly mixing two or more of lithium fluoride, sodium fluoride, calcium fluoride or magnesium fluoride in proportion to prepare a multi-element fluoride coating material; and S3, uniformly mixing the P2-type sodium-ion battery nickel-manganese-based layered oxide and the multi-fluoride coating material according to a ratio, and then carrying out high-temperature quenching treatment to obtain the surface fluoride-coated and near-bulk-phase-doped dual-modified sodium-ion battery layered oxide positive electrode material. According to the dual-modified layered oxide positive electrode material for the sodium-ion battery and the preparation method, surface fluoride coating and near bulk phase doping are cooperatively utilized, so that the high-voltage cycle performance of the layered oxide positive electrode material for the sodium-ion battery is improved.

The present disclosure provides a method of recovering a spent battery cathode material comprising lithium and at least one of nickel, cobalt and / or manganese, the method comprising: heating the spent battery cathode material in a reducing atmosphere to form a heat-treated spent battery cathode material comprising LiF and one or more of LijO, LiOH and LijCOs; washing the heat treated waste battery cathode material in an aqueous solvent to extract lithium-containing species and fluorine-containing species wherein the aqueous solvent is free of alkaline earth metal hydroxides or other species intended to reduce or prevent soluble fluorine species from remaining dissolved in the aqueous solvent; separating an aqueous solvent comprising lithium and fluorine species from the heat treated waste battery material; after separating an aqueous solvent comprising lithium and fluorine species from the heat-treated waste battery material, treating the aqueous solvent to separate lithium species from fluorine species; recycling a lithium substance in the form of lithium hydroxide or lithium carbonate; forming an acidic aqueous recovery feed comprising one or more of nickel, cobalt and / or manganese by leaching the heat treated waste battery cathode material with a mineral acid after the step of separating the aqueous solvent from the heat treated waste battery material; and recovering one or more of nickel, cobalt and / or manganese from the acidic aqueous recovery feed by a further process step selected from one or more of solvent extraction, solid phase extraction, electrochemical extraction and precipitation processes.

The invention provides a boron gradient-doped positive electrode precursor and a preparation method thereof, a positive electrode material and a battery. The positive electrode precursor comprises a boron-doped ternary material core and a boron-doped ternary material layer coated outside the boron-doped ternary material core, the mass fraction of the boron element in the boron-doped ternary material core is lower than that of the boron element in the boron-doped ternary material layer. In the boron gradient-doped positive electrode precursor provided by the invention, boron doping is performed in the boron-doped ternary material core and the boron-doped ternary material layer, so that a B-O bond with relatively high bond energy is formed, and lattice stress accumulation in the positive electrode precursor is reduced, thereby improving the structural stability and thermal stability of the positive electrode precursor and the positive electrode material; in addition, through gradient doping of boron, the electrochemical performance of the positive electrode material is ensured, the surface and interface structure of the positive electrode precursor is strengthened, the expansion of cracks is inhibited, and the structural stability of the positive electrode precursor is improved.

The present invention provides a method for producing lithium hydroxide, comprising the steps of reacting lithium carbonate and calcium hydroxide in a liquid to obtain a solution containing lithium hydroxide, and performing solid-liquid separation on the solution into a liquid component containing lithium hydroxide and a solid component containing lithium derived from the lithium carbonate, and recovering lithium hydroxide from the liquid component.

The invention discloses a salt lake brine evaporative crystallization method and device, and the crystallization method comprises the following steps: spreading and straightening a brine absorbing cloth, setting the included angle between the brine absorbing cloth and the horizontal plane to be 80-90 degrees, immersing the lower end of the brine absorbing cloth in brine, and carrying out evaporative crystallization; after evaporative crystallization, the lower end of the halogen absorbing cloth is removed from the brine, and salt on the halogen absorbing cloth is collected; the aperture of the halogen absorbing cloth is lt; the top end of the halogen absorbing cloth is positioned at the height gt above the brine; 7 m. Under the action of wind energy and solar energy, the brine evaporation speed of the brine absorption cloth per unit area is more than 20 times that of the salt pan solar pond per unit area, and the occupied area of the evaporation device and the salt pan can be effectively reduced.

The invention provides a preparation method of battery-grade lithium salt, and relates to the technical field of new energy materials. Starting from battery-grade lithium sulfate, part of lithium sulfate is reduced under hydrogen to obtain battery-grade lithium sulfide; part of lithium sulfate reacts with sodium carbonate to obtain battery-grade lithium carbonate, the battery-grade lithium carbonate reacts with hydrochloric acid to obtain lithium chloride, lithium chloride is electrolyzed to obtain metal lithium, and the metal lithium reacts with sulfur, is reduced and is converted into battery-grade lithium sulfide; part of lithium sulfate reacts with sodium hydroxide to obtain battery-grade lithium hydroxide, and then the battery-grade lithium hydroxide reacts with hydrogenation tail gas to obtain battery-grade lithium sulfide. Further, the battery-grade lithium sulfide can be obtained from the lithium-containing ore through the steps of calcination, sulfuric acid leaching, purification and the like. Through conversion and adjustment among different lithium salts, the cost of the lithium sulfide can be adjusted according to different conditions, and low-cost and large-scale mass production of the lithium sulfide is realized.

The present disclosure provides various characteristics for treating tail brine extracted from a bromine plant, when said brine contains residual bromine and chlorine with low pH and high ORP values that will be used in a lithium extraction production facility. The method conditions the extracted tail brine by adding either sodium hydroxide or ammonium hydroxide to bring its pH levels to between 5.5 and 6.5. The conditioned tail brine then gets pre-treated with hydrazine in either less than 70 ppm if used in combination with sodium hydroxide; or 195 ppm if used with ammonium hydroxide until the ORP levels have reached to below 100 mV. The extracted tail brine is then processed through DLE processing device having four groups of adsorption columns filled with lithium adsorption resins that, after treating the extracted tail brine, discharges the raw eluate solution to an effluent tail brine tank using an effluent tail brine pump connected to the DLE processing device.

The invention discloses a method for circularly leaching lithium iron phosphate mixed powder from ferric salt and recovering all components, and belongs to the field of battery recovery. The method comprises the following steps: leaching mixed powder by adopting an iron salt solution to obtain a lithium-containing leaching solution and leaching residues; ferrous ions in the leachate are regenerated into ferric iron through acidification and oxidation, the ferric iron is cyclically used for leaching the next batch of mixed powder, after the preset cycle number is reached, the leachate is used for re-leaching treatment of multiple batches of leaching residues, and the lithium leaching rate is increased. And finally obtaining enriched liquid containing Li, Fe, Cu and Al and iron phosphate slag containing graphite. And replacing the enriched liquid with iron powder to recover copper, extracting and separating to obtain a high-purity lithium chloride solution, and simultaneously recovering ferric chloride (recycling) and aluminum chloride crystals. And treating the leaching residues with hydrochloric acid to obtain regenerated graphite, and adjusting the pH value with alkali to obtain high-purity iron phosphate. According to the method, all-component recovery is achieved under the mild condition, separation steps are reduced through a leaching-regeneration-leaching circulation mechanism, chemical consumption is reduced, and the method has both environmental and economic benefits.

Producing high purity lithium solution from a source brine containing at least 1 mg Li / kg brine, preferably 10 mg / kg, more preferably 25 mg Li / kg brine; treating the source brine, if necessary in pretreatment steps; processing the treated brine in a lithium adsorption step; after the adsorption step, desorbing the adsorbed lithium in a desorption step; after the desorption step, treating the desorption effluent in an enrichment step. Specified optional steps and new features can be used to increase lithium concentrations and purity.

The invention relates to a method for high-value recovery of a positive electrode material of a waste lithium iron phosphate battery, which mainly comprises the following steps: adding a lithium iron phosphate positive electrode material, ammonium chloride and hydrogen peroxide into a ball milling tank for grinding, controlling the mass ratio of the ammonium chloride to the lithium iron phosphate positive electrode material to be 5: 2-7: 2, and controlling the volume mass ratio of the hydrogen peroxide to the lithium iron phosphate positive electrode material to be (18-22): 1mL / g; after grinding, washing out the mixture from the ball-milling tank by using deionized water, and then carrying out water leaching treatment to fully leach out metal lithium; excessive ammonium fluoride is added into the filtrate, and reaction liquid and a product lithium fluoride are obtained after reaction; and carrying out adsorption treatment on the reaction liquid by using defluorination resin, regenerating the defluorination resin through elution, combining and concentrating the collected effluent and eluent to obtain an ammonium chloride solution, and recycling the ammonium chloride solution to a chlorination reaction stage. According to the invention, through H2O2 reinforced mechanical chlorination coupling fluorination reaction, nearly total recovery of the waste lithium iron phosphate battery positive electrode material and high value of the product are realized, and the process is simpler and more environment-friendly.

The present disclosure introduces advanced techniques for critical mineral processing using solid electrolyte membranes. In particular, a novel electrolytic and environmental direct lithium extraction (MOBILE) process, may be used comprising an extractor unit featuring alternating lithium and sodium storage modules, a lithium collection tank, and a precipitation stage. The MOBILE process offers several key advantages over traditional methods, including enabling selective lithium extraction from low-concentration feed solutions while reducing chemical consumption and minimizing environmental impact. Furthermore, the MOBILE process demonstrates faster extraction times and superior adaptability to diverse feed solution compositions. Its modular and scalable design allows for flexible adaptation to various feed solutions and production capacities, making it a versatile solution for lithium extraction across different scenarios. The MOBILE process represents a significant advancement in critical mineral processing, offering a more efficient, environmentally friendly, and adaptable method for lithium extraction and related mineral processing applications.

The invention belongs to the technical field of batteries, and particularly discloses a lithium manganese iron phosphate material and a preparation method thereof, a secondary battery and an electric device. The lithium iron manganese phosphate material comprises an inner core and a shell, wherein the inner core is lithium iron manganese phosphate coated with lithium iron phosphate; the shell is positioned on at least part of the surface of the inner core; the shell comprises a fluorine-containing passivator and a carbon material, and based on the total mass of the lithium manganese iron phosphate material, the mass percentage content of fluorine is 0.5%-2.0%, and the mass percentage content of carbon is 1.0%-2.0%. The lithium manganese iron phosphate material has good structural stability and strong conductivity, and is convenient for the battery to give consideration to cyclicity and gram volume exertion at the same time.

The invention relates to a surface-modified co-doped lithium-rich manganese-based positive electrode material and a preparation method thereof. The surface-modified co-doped lithium-rich manganese-based positive electrode material comprises a bulk phase part and a surface part, the bulk phase part is a cation co-doped lithium-rich manganese-based material, the chemical formula is Li < 1.2 > Ni < 0.17 > Co < 0.16-x > M < x > Ru < y > Mn < 0.47-y > O < 2 >, in the formula, M is at least one of V, Cr and Fe, x is more than or equal to 0.06 and less than or equal to 0.14, and y is more than or equal to 0.05 and less than or equal to 0.2; the surface part is a selenium-halogen composite modified layer coating the bulk phase part in situ, contains selenide and lithium halide, and is formed by heat treatment of a bulk phase material, a selenium source and a halogen source in an inert atmosphere. The positive electrode material provided by the invention has excellent structural stability and high lithium ion diffusion coefficient, has good interface compatibility with halide electrolyte, and has high energy density and long cycle stability when being used in a halide all-solid-state battery.

The present invention provides a method for recovering lithium and iron phosphate from waste lithium iron phosphate. The method comprises: providing a crude lithium iron phosphate residue; formulating the crude lithium iron phosphate residue into a slurry, and introducing Cl2 gas into the slurry, while adding FeCl3 as a catalyst, to carry out a catalytic oxidation lithium extraction reaction; filtering the reacted slurry to obtain a lithium-containing filtrate and a crude iron phosphate filter residue; crystallizing lithium chloride from the lithium-containing filtrate to obtain purified lithium chloride; subjecting the crude iron phosphate filter residue to acid leaching, followed by filtration to obtain an iron phosphate precursor; and calcining the iron phosphate precursor to obtain iron phosphate. The method of the present invention enables full-element recovery of lithium iron phosphate from waste lithium iron phosphate, and can improve the energy utilization rate.

The embodiment of the invention provides a halide electrolyte with a core-shell structure, a preparation method and a solid-state battery. The halide electrolyte with the core-shell structure comprises an inner core and a coating layer coating the surface of the inner core. Wherein the inner core is a crystalline halide electrolyte, the coating layer is an amorphous sulfide electrolyte, and the amorphous sulfide electrolyte comprises LiBr, LiI and Li3PS4. According to the scheme, the conductivity and the air stability of the halide electrolyte with the core-shell structure are effectively improved.

The invention provides a lithium ion battery negative electrode material as well as a preparation method and application thereof. The lithium ion battery negative electrode material is a porous silicon carbon material coated with lithium phosphate. The preparation method is simple and efficient, lithium phosphate salt is uniformly distributed on the surface of the porous silicon carbon material through solvent wet coating, the lithium phosphate salt is decomposed into LiF and LixPyOz through sintering and heating, and LiF and LixPyOz coating layers are generated in situ on the surface of the porous silicon carbon negative electrode material of the lithium ion battery, so that the porous silicon carbon material uniformly coated with LiF and LixPyOz is obtained, the advantages of LiF and LixPyOz are combined, and the porous silicon carbon material has the advantages that the porous silicon carbon material can be used for preparing the lithium ion battery negative electrode material through cooperation of LiF and LixPyOz; the silicon-carbon material prepared by the method has the characteristics of high strength, high stability and high ionic conductivity, can effectively inhibit volume expansion of the silicon-carbon material in the charge-discharge process, block penetration of electrons and reduce capacity loss of the silicon-carbon material in the reaction process, is used for manufacturing a lithium ion battery and remarkably improves the cycling stability of the battery.

Pairing of Li2ZrCl6 (LZC) and Li6PS5Cl (LPSC) solid electrolytes, which increases the effective electrochemical and chemical stability window of the electrolyte of lithium-based solid-state batteries, and enables stable cycling with a high voltage cathode and a metallic anode, with the potential to greatly enhance solid-state battery energy density.

The invention provides a residual alkali in-situ conversion LiF-Li3PO4-LiAlO2 coating layer-based repaired and regenerated ineffective ternary positive electrode material and a preparation method and application thereof. The preparation method comprises the following steps: S1, mixing, grinding and calcining an ineffective ternary material and Li2CO3 or LiOH.H2O to obtain a repaired ternary material; and S2, mixing the repairing ternary material with NH4F or NH4H2PO4 or Al2O3, grinding, and calcining, so as to obtain the LiF-Li3PO4-LiAlO2 in-situ co-coated NCM positive electrode material. When the prepared LiF-Li3PO4-LiAlO2 in-situ co-coated LiNi < x > Co < y > Mn < z > O < 2 > (NCM) positive electrode material is used as a positive electrode material of a lithium ion battery, the air stability, the thermal stability and the electrochemical stability of the material can be effectively improved, so that the high-value recovery of invalid LiNi < 0.5 > Co < 0.2 > Mn < 0.3 > O < 2 > (NCM < 523 >) is realized. And the method reduces the residual lithium salt on the surface of the regenerated material, and compared with a common recovery method, the interface stability is effectively improved.

The invention pertains to a recycling process of a material comprising a halide solid electrolyte (HSE) of formula (I) M3-z(Mek+)fX3-z+k*f, said process comprising successively: a) adding at least one ammonium salt of X' to a solution comprising the HSE, wherein X and X' are halogens, in particular independently chosen from Cl, Br, I and any combination thereof; b) filtering and evaporating the solution obtained in step a) to obtain a dry powder; c) heating the dry powder obtained in step b), and d) obtaining a recycled HSE of formula (I). The invention further concerns a cathode composite and an electrolyte comprising a recycled HSE obtained from the recycling process according to the invention and an all-solid-state battery comprising such a cathode composite and / or electrolyte.

The present disclosure discloses a raw brine treatment system, a raw brine treatment method, and a lithium compound. The raw brine treatment system includes: an ion exchange adsorption unit (100), where the ion exchange adsorption unit (100) includes one or more adsorption columns (110), a part of raw brine to be treated is subjected to adsorption treatment in an adsorption process (111) and then subjected to desorption treatment with desorption water in a desorption process (112); a desorption water extraction unit (200), where another part of the raw brine to be treated and / or a part of adsorption tail solution of the ion exchange adsorption unit (100) enters the desorption water extraction unit (200), the desorption water extraction unit (200) is configured to extract the desorption water from the raw brine and / or the adsorption tail solution that enters the desorption water extraction unit (200), and the desorption water extraction unit (200) is connected to the ion exchange adsorption unit (100); and a recovery unit (300), where the recovery unit (300) is connected to the ion exchange adsorption unit (100) and the desorption water extraction unit (200).

The present invention relates to a method for improving the yield of a lithium solution through concentration and crystallization, and, more specifically, to improving the yield of a lithium solution by reacting a low-concentration lithium solution with a fluorine compound so as to prepare lithium fluoride, and then concentrating and crystallizing a filtrate.