2240 results about "Lithium" patented technology

Processes for extracting lithium from a clay mineral and compositions thereof are described. The extraction process includes providing a clay mineral comprising lithium, mixing a cation source with the clay mineral, performing a high-energy mill of the clay mineral, and performing a liquid leach to obtain a lithium rich leach solution.

A solid electrolyte includes: LiaAbEc(SO4)dJeXfHh, A is selected from alkaline earth metals and alkali metals other than Li, E is selected from Al, Ga, In, Sc, Y, Ti, Zr, Hf, and lanthanides, J is selected from OH, BO2, BO3, BO4, B3O6, B4O7, CO3, NO3, AlO2, SiO3, SiO4, Si2O7, Si3O9, Si4O11, Si6O18, PO3, PO4, P2O7, P3O10, SO3, SO5, S2O3, S2O4, S2O5, S2O6, S2O7, S2O8, BF4, PF6, BOB, (COO)2, N, AlCl4, CF3SO3, CH3COO, CF3COO, OOC—(CH2)2—COO, OOC—CH2—COO, OOC—CH(OH)—CH(OH)—COO, OOC—CH(OH)—CH2—COO, C6H5SO3, OOC—CH═CH—COO, OOC—CH═CH—COO, C(OH)(CH2COOH)2COO, AsO4, BiO4, CrO4, MnO4, PtF6, PtCl6, PtBr6, PtI6, SbO4, SeO4, TeO4, HCOO, and O, X is selected from F, Cl, Br, and I, 0.5≤a<6, 0≤b<6,0<c<2,0.1<d≤6.0, 0<e≤6.0, 0<f≤6.1, and 0≤h≤0.2, and a peak is observed at a diffraction angle 2θ=22.3°±1.0° in an X-ray diffraction pattern in which Cu-Kα is used as a line source.

The invention discloses a method for harmlessly treating lithium slag and preparing a water-stable material from the treated lithium slag. The method comprises the following steps: crushing the lithium slag; mixing a sulfuric acid-containing material with the crushed lithium slag to obtain a pulpified mixture; roasting, and carrying out chemical modification to obtain roasted slag; adding a material containing activated aluminum oxide into the roasting slag to obtain a mixed material; the mixed material is subjected to water leaching and filtering, and leaching residues and leaching liquid are obtained; and drying the leaching slag, adding an exciting agent, and grinding to finally obtain the detoxified lithium slag. And preparing the water-stable material from the detoxified lithium slag. Under the condition of effectively improving the quality of the cement-stabilized layer, the lithium slag resource is effectively utilized, the resource utilization rate is improved, and the mechanical strength and corrosion resistance of the cement-stabilized layer concrete can be effectively improved by matching with the exciting agent and the curing agent.

The invention discloses a uniformly radial positive electrode material precursor and a preparation method thereof. The cross section of the uniformly radial positive electrode material precursor is uniformly radial, and the shape of the uniformly radial positive electrode material precursor is divided into a core and an outer layer, the core is loose and porous, and the outer layer is in a regular radial shape; the method adopts a coprecipitation method to carry out two-stage reaction preparation, in the first reaction stage, an inner core layer is prepared; a second reaction stage: preparing a shell layer to reach a target particle size; the secondary particle D50 is 6.0-14.0 microns, the TD is greater than 1.90 g / cm, and the BET is less than or equal to 14m < 2 > / g; the precursor is small in structure core and compact in outer layer, particles grow in a radial mode from inside to outside, lithium ions can be separated and embedded out easily, the particle structure is more stable, and excellent rate performance and cycling stability are shown; a staged coprecipitation method is adopted, and controllable growth of a particle structure is realized by accurately controlling the ratio of oxygen to nitrogen and reaction conditions; according to the whole process design, the complex parameter adjusting range is reduced, and the production stability and repeatability are improved.

The invention relates to the technical field of cement clinker preparation, and particularly discloses a calcium sulphosilicate mineral clinker with high carbonization activity, a raw material and a preparation method and a hardening method of the calcium sulphosilicate mineral clinker. The clinker is prepared from the following mineral phases: 87.2 to 95.1 percent of calcium sulphosilicate, 2.6 to 9.5 percent of dicalcium silicate and the balance of unreacted raw materials, inevitable impurities and the like. Part of calcium elements in crystal lattices of the calcium sulphosilicate are replaced by at least one of lithium elements, sodium elements, potassium elements and strontium elements. The hardening method comprises the following steps: mixing the calcium sulphosilicate mineral clinker with water, and curing in a carbon dioxide environment to obtain the calcium sulphosilicate mineral hardened body. The mineral clinker disclosed by the invention has excellent carbonization activity, so that the mineral clinker can react with carbon dioxide to obtain high strength, high carbon sequestration is realized, carbon emission is reduced, and the mineral clinker has excellent mechanical properties.

The invention provides analcime based on alkali grinding activation as well as a preparation method and application of the analcime. The preparation method of analcime comprises the following steps: S1, providing lithium slag; s2, ball-milling the solid material and water together to obtain a ball-milled product; the solid material comprises the lithium slag and an alkaline auxiliary material, and the alkaline auxiliary material comprises one or more of sodium hydroxide and potassium hydroxide; s3, mixing the ball-milled product with an alkaline solution to obtain a to-be-treated solution; performing hydro-thermal treatment on the to-be-treated liquid to obtain reaction liquid; and S4, carrying out solid-liquid separation on the reaction liquid to obtain a solid isolate containing analcime. The analcime with high crystallinity and high yield can be obtained, a new way is provided for preparation of the analcime, and a new way is also provided for resourceful treatment of the lithium slag.

The invention belongs to the technical field of energy storage materials, and particularly relates to a high-entropy oxide Fe0. 2Co0. 2Ni0. 2Cu0. 2Zn0. 2O and an ultrafast synthesis method and application thereof. According to the preparation method, ferroferric oxide, cobalt oxide, nickel oxide, copper oxide and zinc oxide with equal molar ratio are adopted as direct synthesis raw materials, toxic gases such as chlorine and nitrogen dioxide generated in the synthesis process of a metal salt precursor are avoided, and the uniformly distributed single-phase high-entropy oxide is synthesized in an ultrafast manner within 10 seconds by using a Joule heating technology; the synthesized high-entropy oxide is used as a lithium ion battery negative electrode material, and shows more excellent electrochemical performance and cycling stability compared with other high-entropy oxides prepared from transition metals with different proportions; in the preparation process, extra additives are not needed, operation is easy, the synthesis speed is high, the yield is high, element distribution is uniform, and the method has the advantages of being low in cost, high in efficiency and free of pollution and has the industrialization prospect.

The invention provides a leaching agent for removing thallium and beryllium in lithium slag and application. The leaching agent comprises a first leaching agent and a second leaching agent. The first leaching agent is an organic acid solution, and organic acid comprises carboxyl and at least one group of hydroxyl, sulfydryl, carbonyl and sulfonic acid group; the organic acid is single organic acid or mixed organic acid; the second leaching agent comprises a cationic agent and a reducing agent, the cationic agent can form at least one of K < + >, NH4 < + >, Mg < 2 + >, Na < + > and Fe < 3 + > in an aqueous solution, and the reducing agent comprises an inorganic reducing agent and / or an organic reducing agent. Organic acid in the first leaching agent can destroy the crystal structure of the lithium slag, and meanwhile groups such as carboxyl and hydroxyl can be complexed with thallium and beryllium ions so that the thallium and beryllium ions can be dissolved out more easily. On the basis, cations in the second leaching agent and the reducing solution accelerate the release of thallium and beryllium through ion exchange and reduction effects. The leaching agent can remove thallium and beryllium in the lithium slag at the same time, and the removal rate of thallium and beryllium is high.

Provided in the present application are a lithium-rich manganese-based precursor material, and a preparation method therefor and the use thereof. The preparation method comprises the following steps: in a protective gas atmosphere, mixing a nickel-cobalt-manganese mixed salt solution, a precipitator solution and a complexing agent solution, subjecting same to a co-precipitation reaction until particles enter a growth stage, starting the introduction of an oxygen-containing gas, and then continuously subjecting same to the co-precipitation reaction, so as to obtain a lithium-rich manganese-based precursor material. In the preparation method of the present application, by introducing the oxidizing atmosphere in the growth stage of the precursor material, the problems of compact particle growth, being prone to agglomerating and poor morphology in the existing preparation process for a lithium-rich manganese precursor material are solved, and a lithium-rich manganese-based precursor material having high dispersity and a high specific surface area is obtained.

The invention discloses a method for selectively extracting rubidium from lithium ore tailings in a short process, and relates to the field of comprehensive utilization of mineral waste. The method comprises the following steps: grinding the lithium ore tailings into powder; adding an additive into the lithium ore tailing powder, and fully stirring and mixing; roasting the mixture to obtain a calcined clinker; directly carrying out water leaching on the calcined clinker; rubidium enrichment liquid and leaching residues are obtained from the leaching liquid through solid-liquid separation; the rubidium extraction composite material is mixed with rubidium enrichment liquid, and selective adsorption of rubidium is achieved; and recycling the composite material, and the like. According to the method, efficient selective recovery of rubidium in the lithium ore tailings is achieved, the water leaching time is shortened, the water leaching temperature and the rubidium extraction roasting reaction temperature are reduced, the separation efficiency of impurities in the lithium ore tailings and the selective recovery efficiency of the rubidium element are remarkably improved, and efficient selective recovery of rubidium in the lithium ore tailings is achieved.

The present disclosure relates to the extraction of lithium from underground reservoirs of naturally occurring brines. Described herein are systems and methods to extract lithium entrapped within reservoirs that were previously inaccessible.

A positive electrode active material may include a compound represented by formula 1 or formula 2: Li(1.333−0.667x−y)Mn(0.667−0.333x)NixA(y−a)MaO2 (1), Li(1.333−0.667x−z−a)Mn(0.667−0.333x−0.5y)Ni(x−0.5y+z)A(y+a−b)MbO2 (2). A is Co, Cr, or a combination thereof, M is W+6, Ta+5, V+5, or a combination thereof, 0<x<0.5, 0<y<0.333, 0<x<0.04, 0<x−0.5y+z<0.5, 0<y+a−b<0.333, and 0<b<0.04.

The invention discloses a lithium-rich manganese-based positive electrode material with a core-shell structure, the general formula of the lithium-rich manganese-based positive electrode material is Li < 1 + a > Mn < x > Co < y > Ni < z > O < 2-b-d > (XOc) X < d >, the lithium-rich manganese-based positive electrode material has the core-shell structure, the core is a lithium-rich manganese-based material Li < 1 + a > Mn < x > Co < y > Ni < z > O < 2-b > (XOc) doped with disordered polyanions, and the shell is a lithium-rich manganese-based material Li < 1 + a > Mn < x > Co < y > Ni < z > O < 2-d > X < d > doped with gradient non-metal ions. The invention also provides a preparation method of the lithium-rich manganese-based positive electrode material with the core-shell structure, and the lithium-rich manganese-based positive electrode material with the core-shell structure is prepared by adopting a combined means of rapid Joule heat treatment and surface plasma cleaning treatment. The polyanion-doped bulk phase disordered structure design and the surface gradient non-metal ion-doped core-shell structure are realized. Wherein the bulk phase polyanions can fix transition metal elements to inhibit migration of the transition metal elements to a lithium layer, harmful consumption of active sites is reduced, and a lattice structure is stabilized. In addition, strong bond energy between surface nonmetal and transition metal elements can inhibit dissolution of transition metal in the circulation process, irreversible oxidation of oxygen is reduced, and generation of harmful phase change is inhibited.

The invention discloses a method for selectively recycling phosphorus pollutants in low-concentration phosphorus-containing sewage and preparing high-quality blue iron ore and application, and belongs to the technical field of water treatment and recycling thereof. According to the method, the low-concentration phosphorus-containing sewage is adsorbed by a phosphorus specific nano adsorption material HFO-201, and then the material is desorbed by adopting sodium hydroxide and sodium chloride with specific concentrations. The desorbed filtering material and the filtered material can be repeatedly used for adsorbing phosphorus in low-concentration sewage. After the pH value of the filtered desorption solution is adjusted to a certain concentration, FeCl2 with a certain concentration is added, and high-quality blue iron ore (Fe3 (PO4) 2.8 H2O) can be generated by keeping the pH value through sodium hydroxide under an anaerobic condition. The phosphorus product recovered by the process can be used for preparing a high-value phosphate fertilizer and a high-energy-density energy storage material, namely lithium iron phosphate (LiFePO4). The HFO-201 used in the invention can realize low-concentration phosphorus adsorption through an ammonium group combined with a D-201 matrix and loaded HFO nanoparticles. And moreover, after alkali desorption, the damage to the material is very low, and the material can be repeatedly used. And finally, the process of producing the high-quality blue iron ore through phosphorus recovery of the desorption solution is simple and easy to operate. Through XRD, ICP and other detection, it is found that the phosphorus recovery product is determined to be the blue iron ore, and the purity is very high. Through economic analysis and life cycle evaluation, it can be found that the method has remarkable economical efficiency, and the influence on the environment in the production process is small.

A positive electrode active material may include a compound represented by formula 1 or formula 2: Li1.10Mn0.52Ni(0.38-x)A(x-a)MaO2 (1), Li1.12Mn0.51Ni(0.37-x)A(x-a)MaO2 (2). A is Co, Cr, or a combination thereof, M is W+6, Ta+5, V+5, or a combination thereof, 0<x<0.1, 0<a<0.04, and 3.8<average oxidation state of Mn ion<4.0.

The invention provides a method for preparing a lithium slag-based molecular sieve by melting lithium slag with assistance of eutectic salt, and relates to the technical field of molecular sieves. The method comprises the following steps: carrying out acid pickling pretreatment on a lithium slag raw material to obtain pretreated lithium slag; co-grinding and uniformly mixing the pretreated lithium slag and eutectic salt, and reacting at 200-350 DEG C for 2-6 hours to obtain eutectic lithium slag; carrying out aging treatment and crystallization treatment on the eutectic lithium slag, carrying out solid-liquid separation, washing the solid to be neutral, and drying to obtain a lithium slag-based molecular sieve; wherein the eutectic salt comprises an alkali solvent and an auxiliary salt, the alkali solvent is sodium hydroxide, and the auxiliary salt is at least one of chlorine salt, villiaumite, carbonate, sulfate and nitrate; the molar ratio of the alkali flux to the auxiliary salt is (4-19): 1. According to the method, the eutectic salt system is introduced in the lithium slag alkali fusion stage, meanwhile, the molar ratio of the alkali flux to the auxiliary salt in the eutectic salt is controlled to be (4-19): 1, the alkali fusion reaction temperature is reduced, the reaction of the lithium slag and alkali is promoted, the molecular sieve yield is increased, the product morphology can be regulated and controlled, and a specific molecular sieve can be formed in a guiding mode.

The invention provides a positive active material with a lithium fluoride layer as well as a preparation method and application of the positive active material. The positive active material comprises a high-nickel ternary positive material and the lithium fluoride layer covering the surface of the high-nickel ternary positive material, and the thickness of the lithium fluoride layer is 10-100 nm. In the positive electrode active material with the lithium fluoride layer, the surface of the high-nickel ternary positive electrode material is covered with the lithium fluoride layer, and lithium fluoride has excellent chemical stability, conductivity and lithium ion transmission rate, so that the positive electrode active material is coated with the lithium fluoride layer with the thickness of 10-100nm, thereby ensuring that the positive electrode active material has relatively good ion transmission performance; the internal strain and phase change of the high-nickel ternary positive electrode material are inhibited, and the risk that the high-nickel ternary positive electrode material generates cracks is reduced; the interface performance is improved, and the active material is isolated from the electrolyte, so that the risk of side reaction between the high-nickel ternary positive electrode material and the electrolyte is reduced, and the high-nickel ternary positive electrode material is prevented from being dissolved and delithiated.

The invention discloses a titanium-based lithium ion sieve and a preparation method thereof, the titanium-based lithium ion sieve comprises a lithium titanium oxide and a cerium-based solid solution, and the cerium-based solid solution comprises oxygen vacancies; in a Raman spectrum of the cerium-based solid solution, the peak intensity ratio I < 603 + / -0.2 > / I < 465 + / -0.2 > of spectrum peaks at the positions of 464.8 cm <-1 > to 465.2 cm <-1 > and the positions of 602.8 cm <-1 > to 603.2 cm <-1 > is equal to 0.05-0.3. When the titanium-based ion sieve provided by the embodiment of the invention is used for an adsorbent, the titanium-based ion sieve has the advantages of high adsorption efficiency, low solution loss rate, stable structure, good reusability and the like.

The invention provides a detoxification method and system based on nanofiltration treatment of lithium ore smelting slag, and the method comprises the following steps: step S1: carrying out acid leaching treatment on the lithium ore smelting slag by using an inorganic acid liquid, so that acid-soluble components in the lithium ore smelting slag are dissolved in the inorganic acid liquid to obtain an acid leaching liquid and detoxified smelting slag; s2, the acid leaching solution is subjected to oxidation treatment, metal ions with intermediate valence in the acid leaching solution are oxidized into metal ions with high valence, and an oxidized acid leaching solution is obtained; s3, carrying out nanofiltration treatment on the oxidized pickle liquor to intercept high-valence metal ions in the oxidized pickle liquor so as to obtain concentrated liquor and permeate liquor; s4, using the permeate liquid as the inorganic acid liquid in the step S1 for acid leaching treatment. According to the method, toxic components in the lithium ore smelting slag can be fully separated, and resource utilization is easier.

The invention discloses a double-site doped titanium lithium ion sieve adsorbent as well as a preparation method and application thereof. The adsorbent is a lithium removal product of a double-site doped titanium lithium ion sieve adsorbent precursor, the chemical general formula of the double-site doped titanium lithium ion sieve adsorbent precursor is Li (2-x) MxTi (1-y) NyOz, M is at least one of Na < + >, K < + >, Zn < 2 + >, Co < 2 + >, Ni < 2 + >, Mg < 2 + > and Al < 3 + > and occupies Li site, N is at least one of Cr < 3 + >, Fe < 3 + >, Zr < 4 + >, Nb < 5 + >, Ta < 5 + >, V < 5 + >, Mo < 6 + > and W < 6 + > and occupies Ti site, x is larger than or equal to 0.001 and smaller than or equal to 0.5, and y is larger than or equal to 0.001 and smaller than or equal to 0.5. Metal cations are introduced to replace Li sites and Ti sites at the same time, Li site substitution enlarges interlayer spacing and improves Li < + > diffusion rate, Ti site substitution regulates local chemical bond and electron distribution, stabilizes lattice structure and enhances electron conduction, and through double-site doping, 'ion-electron 'double channels are constructed, so that a collaborative optimization effect is achieved. The double-site doped titanium lithium ion sieve adsorbent disclosed by the invention is applied to adsorption and extraction of lithium in a Bayer process sodium aluminate solution, and the adsorbent shows excellent adsorption performance.

The invention discloses a composite separation membrane for enriching < 6 > Li isotope and application. The composite separation membrane comprises a functional membrane and at least one supporting membrane; the functional film comprises a plurality of pore channels penetrating through the first surface and the second surface of the functional film, and the pore channel diameter of each pore channel is 0.4-0.7 nm; a lithium ion trapping functional group or a macrocyclic compound and a derivative thereof are modified at an inlet of the first surface of the pore channel. The strength of the lithium isotope separation effect depends on the diameter of a pore channel of the composite separation membrane and functional groups modified at an inlet, does not change along with the migration time and the lithium ion migration proportion, and has long-term continuous stability.

The invention relates to the technical field of new energy, in particular to a nickel-free lithium-rich manganese-based positive electrode material and a preparation method thereof. The preparation method comprises the following steps: (1) preparing a precursor: mixing a lithium source, a sodium source and a manganese source according to a stoichiometric ratio of a chemical formula # imgabs0 #, grinding, and calcining in an oxidizing atmosphere to form a P3 type layered precursor; (2) ion exchange: mixing the P3 type layered precursor obtained in the step (1) with a lithium salt, and carrying out sodium-lithium ion exchange through a solid-phase reaction to form a sodium-deficient intermediate; and (3) annealing treatment: carrying out heat treatment on the material subjected to ion exchange to obtain the lithium-rich manganese-based positive electrode material with the O3 type layered structure. According to the invention, only substances composed of three elements of Li, Mn and O are used for synthesizing the positive electrode material, so that the use of materials containing cobalt and nickel is avoided.

The invention discloses a method for simultaneously extracting lithium and silicon from a lithium-containing mineral, which comprises the following steps: carrying out reduction reaction on the lithium-containing mineral under the action of a metal reducing agent to prepare a reduction product, and carrying out atmosphere ball milling and water leaching on the reduction product in an inert gas atmosphere to obtain a lithium-rich water leaching solution and a first solid; carrying out first dilute acid leaching on the first solid to obtain a lithium-rich pickle liquor and a second solid; obtaining a silicon nanomaterial from the second solid; the lithium-rich pickle liquor or a mixture of the lithium-rich pickle liquor and natural minerals and an alkali solution are dropwise added into water at the same time, stirring is conducted, pH is regulated and controlled, heating stirring is conducted for a period of time for dynamic crystallization, then static crystallization is conducted, and solid-liquid separation is conducted to obtain lithium-rich supernate and a third solid; a layered multi-metal hydroxide is obtained from the third solid. According to the method, a lithium extraction process and a silicon nano material preparation process are coupled, elements such as lithium and silicon in minerals are fully utilized, comprehensive utilization of the elements is realized, waste of resources is avoided, and economic benefits are greatly improved.

The invention relates to a low-temperature graphite negative electrode material and a preparation method thereof, and belongs to the technical field of high polymer materials. According to the prepared low-temperature graphite negative electrode material, firstly, the surface of graphite is pre-oxidized through potassium persulfate, phosphorus pentoxide and concentrated sulfuric acid, and then under the action of sodium nitrate, potassium permanganate and hydrogen peroxide, graphite oxide is prepared; then, ammonium molybdate hydrate and thioacetamide are used as a molybdenum source and a sulfur source, graphite oxide is used as a supporting material, a molybdenum disulfide-graphite compound is synthesized, and the conductivity and the cycling stability are improved; secondly, the surface of the negative electrode is coated with amorphous resin carbon / nickel oxide, so that the ion diffusion efficiency of the low-temperature graphite negative electrode material is enhanced, and the electrochemical lithium storage performance is improved in a low-temperature environment; and finally, the surface of the amorphous resin carbon / nickel oxide is coated with a layer of polythiophene film, so that the rate capability of the negative electrode material is improved due to large surface area and high pores.

The present disclosure provides a field quantitative analysis method and system of lithium, and relates to the technical field of field quantitative analysis of lithium. The method includes: measuring a laser-induced breakdown spectroscopy of a lithium-containing mineral, to obtain spectral data of the lithium-containing mineral; taking the spectral data as an input, and determining a mineral class of the lithium-containing mineral based on a trained mineral classification model; and taking the spectral data as the input, and determining content of lithium in the lithium-containing mineral based on a calibration curve corresponding to the mineral class.

The present invention relates to the extraction of lithium from liquid resources such as natural and synthetic brines, leachate solutions from clays and minerals, and recycled products.

Provided herein are ion-selective separation membranes including a polymer matrix and a metal compound dispersed within the polymer matrix. The metal compound includes HaLibXcOa, where a is from 1 to 1.5, b is from 0 to 0.1, c is from 1 to 2, d is from 4 to 4.5, and X includes manganese or titanium.

The present disclosure relates to the extraction of lithium from liquid resources such as natural and synthetic brines, leachate solutions from clays and minerals, and recycled products.

The invention discloses a technological method for extracting lithium, rubidium and cesium through a lepidolite chlorate method. The technological method comprises the steps that lepidolite, calcium chloride, sodium chloride and calcium oxide are mixed and then roasted, and clinker is obtained; leaching the clinker under an acidic condition to obtain brine; performing impurity removal treatment on the brine to obtain purified clear liquid; performing lithium precipitation on the purified clear liquid through sodium carbonate liquid; the method comprises the following steps: extracting filtered waste liquid subjected to lithium precipitation through an extracting agent and a dispersing agent, washing a rubidium and cesium oil phase obtained by extraction by adopting two-section multi-stage cross flow of different detergents to obtain an organic phase, and carrying out reverse extraction on the obtained organic phase to reversely extract rubidium and cesium into reverse water; and preparing salt from the reverse water in an evaporation drying manner. According to the method, after the lepidolite is subjected to roasting transformation leaching, the leaching rate of lithium can reach 94% or above, the leaching rates of rubidium and cesium can reach 98% or above, the process of extracting lithium, rubidium and cesium from the lepidolite to prepare corresponding salt products is environmentally friendly, energy-saving, low in energy consumption, low in cost and high in extraction rate, and wide industrial application prospects are achieved.

The present invention provides a method for refining crude lithium, and belongs to the technical field of metal purification. The present invention melts the crude lithium material and then performs a first static sedimentation to obtain a supernatant melt 1, a low-impurity crude lithium melt, and a high-impurity crude lithium melt from top to bottom; the supernatant melt 1 is subjected to vacuum distillation under the condition of electromagnetic stirring without a paddle to volatilize low-boiling impurities, and then subjected to a second static sedimentation to form a bottom lithium melt and a supernatant melt 2; the supernatant melt 2 is separated to obtain purified lithium. The present invention performs vacuum distillation under the condition of electromagnetic stirring without a paddle, which not only realizes dynamic distillation of materials, reduces the distillation temperature, and improves the direct recovery rate of lithium, but also prevents the occurrence of cold zones inside to cause condensation and reflux of Na and K, thereby reducing the distillation efficiency and preventing secondary contamination of the product.