1700results about "Lithium carbonates/bicarbonates" patented technology

The invention relates to a waste lithium iron phosphate battery recycling method, in particular to a graded recycling method for lithium, iron, phosphorus and graphite in a waste lithium iron phosphate battery, and belongs to the technical field of lithium ion batteries and resource recycling of the lithium ion batteries. According to the method, the mode that oxidizing roasting and selective leaching are combined is adopted, the leaching rate and selectivity of lithium are effectively improved, the leaching rate of the lithium element is close to 100% under the optimized condition, and limit recovery of the lithium element is achieved; meanwhile, aiming at the problem that iron and phosphorus in the leaching residues are difficult to utilize, a wet ball milling and secondary acid leaching method is combined, phosphorus and iron elements are separated from negative electrode graphite firstly, and graded recovery of iron, phosphorus and graphite is achieved. According to the method, the high recovery rate of lithium is realized, and meanwhile, high-added-value products such as ferric oxide and sodium phosphate are prepared by efficiently recovering ferric phosphate.

A method for recycling waste lithium iron phosphate, belonging to the technical field of material recycling. The method specifically separately reprocesses the precipitate and leachate obtained by separating and leaching waste lithium iron phosphate powder, using membrane concentration to highly enrich the lithium ions in the leachate and fully utilizing the filtrate generated during the treatment process, and ultimately can simultaneously and efficiently recover and obtain lithium salt and iron phosphate products. The entire method can achieve a lithium recovery rate of 95% or greater for waste lithium iron phosphate, the maximum concentration of impurity elements in the obtained iron phosphate not exceeding 5 ppm, and the quality of the iron phosphate product being relatively high.

The present disclosure relates to the field of sodium-ion battery technology, and specifically, to a method for preparing carbon-coated sodium iron fluorophosphate from waste lithium iron phosphate and the application thereof. The method for preparing carbon-coated sodium iron fluorophosphate from waste lithium iron phosphate includes: mixing a waste lithium iron phosphate material with an alkaline solution for reaction, followed by solid-liquid separation, to obtain an aluminum-containing filtrate and a lithium iron phosphate filter residue; mixing the lithium iron phosphate filter residue, aluminum chloride and sodium chloride uniformly, followed by vacuum calcination, to obtain a calcination material; and mixing the calcination material with at least one of a sodium source, an iron source and a phosphorus source uniformly to obtain a mixture to which a fluorine source, a carbon source and a solvent are added for uniformly mixing, followed by drying and calcination sequentially to obtain the carbon-coated sodium iron fluorophosphate. The method has the advantages of low costs, a high added value, a short process, and a high recovery rate, and the carbon-coated sodium iron fluorophosphate obtained from the method has excellent electrochemical performance.

A process and apparatus for lithium ion extraction. The process includes passing a lithium-containing brine through a lithium-adsorbent, then passing a desorption media through the lithium-adsorbent at a temperature above 40℃ to produce a lithium-enriched eluent. The lithium concentration of the eluent is further increased by passing it through a nanofiltration membrane and a reverse osmosis membrane. Preferably, the eluent is passed through these membranes more than once at a temperature above 40℃. The process is energy-efficient, because it is conducted entirely at temperatures above 40℃. Accordingly, there is no need to decrease the temperature of the lithium-enriched eluent before passing it through the nanofiltration membrane and the reverse osmosis membrane. Moreover, there is no need to increase the temperature of the nanofiltration reverse osmosis permeate before passing it through the lithium-adsorbent as a desorption media, nor is there a need to increase the temperature of the enriched lithium stream before lithium precipitation.

The invention provides equipment and a process for extracting lithium from lepidolite frame residues and synthesizing urea gypsum, and relates to the technical field of solid waste resource recycling, the equipment comprises a reaction tank, a sealing plate, a reciprocating motion mechanism and a multi-point detection mechanism; the reciprocating motion mechanism comprises a bidirectional threaded lead screw and a threaded block, the bidirectional threaded lead screw is transversely and rotatably connected to the inner wall of the reaction tank, the threaded block is in threaded connection with the bidirectional threaded lead screw, and the bottom of the threaded block is slidably connected with a guide seat. According to the scheme, when the top of a rotating wheel is in contact with a concave position of a convex plate, a rotating seat can drive a sliding rod and a PH detector to move upwards under the action of a spring, so that the bottom end of the PH detector is separated from filtrate, and a plurality of convex parts are arranged on the convex plate, so that the filtrate is subjected to multi-point real-time detection; lithium ion loss caused by co-precipitation of lithium, iron and aluminum due to over-high local pH value of the filtrate is avoided, and the concentration of the lithium solution is effectively improved.

The invention provides a lithium precipitation mother liquor lithium recovery method based on countercurrent centrifugal extraction. The method comprises the following steps: S1, pretreating a lithium precipitation mother liquor to obtain a lithium-containing pre-extraction solution; s2, conveying the lithium-containing pre-extraction liquid to a centrifugal extraction system, fully mixing the lithium-containing pre-extraction liquid with an organic phase, and sequentially carrying out multi-stage countercurrent centrifugal extraction; performing phase splitting to obtain raffinate and a lithium-loaded organic phase; s3, the lithium-loaded organic phase enters a washing section to be subjected to multi-stage countercurrent centrifugal washing; s4, performing multi-stage countercurrent centrifugal reverse extraction on the washed lithium-loaded organic phase to obtain a lithium-rich solution; and S5, synthesizing the lithium-rich solution and a sodium carbonate solution to obtain the battery-grade lithium carbonate. The lithium recovery method has the characteristics of rapidness, high efficiency, low equipment investment, small occupied area, less extraction agent consumption and short process flow.

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.

The invention provides a method for recycling lithium iron phosphate, which comprises the following steps: S1, obtaining lithium iron phosphate black powder, and washing the lithium iron phosphate black powder by using alkali liquor to obtain aluminum-removed black powder and aluminum-containing lithium filtrate; s2, the aluminum-removed black powder is subjected to acid leaching treatment with acid liquor, and acid leaching liquor is obtained; s3, carrying out reduction precipitation treatment on the acid leaching solution by using a composite reducing agent to obtain a copper-removed leaching solution and solid-phase copper-containing slag; s4, adding a phosphorus source and an oxidizing agent into the copper-removed leaching solution, adding alkali to adjust the pH value, and carrying out oxidation precipitation treatment to obtain iron phosphate precipitate and a first lithium-containing solution; and S5, adjusting the pH value of the aluminum-lithium-containing filtrate in the step S1 by using an acid solution to obtain aluminum filter residues and a second lithium-containing solution. According to the method, iron phosphate with relatively high purity can be obtained; meanwhile, the obtained first lithium-containing solution and the second lithium-containing solution are relatively low in impurity ion content and can be used for obtaining a lithium salt product with relatively high purity.

The invention provides a method for recovering a lithium iron phosphate material from a waste battery, and relates to the technical field of battery material recovery. The method comprises the following steps: pre-treating the waste battery; treating a positive plate; and material recovery. Wherein the positive plate treatment specifically comprises the step of soaking the positive plate by adopting a first soaking agent. And crushing the positive plate soaked in the first soaking agent. Soaking the crushed positive plate in a second soaking agent, and filtering to obtain a first filter residue taking the positive active material as a main component; and drying, grinding and screening the first filter residue to remove impurities so as to obtain the lithium iron phosphate impurity-removed material. According to the method for recovering the lithium iron phosphate material from the waste battery, provided by the invention, impurities in the recovered lithium iron phosphate material can be reduced, and the purity of the recovered lithium iron phosphate material is increased; the performance of the lithium iron phosphate material synthesized again after the lithium iron phosphate in the waste battery is recycled can meet the brand-new battery-grade raw material requirement.

A method including pretreating ground lithium-containing ceramics to form alkali coated ceramics, leaching the alkali coated ceramics to form a leachate comprising a filtrate and a solid residue, preferentially extracting lithium from the filtrate to form a lithium rich solution and a raffinate, precipitating a crude lithium carbonate from the lithium rich solution and purifying the crude lithium carbonate to produce a battery grade lithium carbonate. A method including leaching a slurry comprising lithium-containing ceramics, water, a strong base, and an alkaline earth metal oxide / hydroxide at a pressure ranging from 0 to 1450 psi and at a temperature ranging from 100 to 500°C to form a leached slurry comprising a liquid filtrate and a solid residue, processing the liquid filtrate to recover a lithium-rich organic solution, and processing the lithium-rich organic solution to produce a battery-grade lithium compound and sodium sulfate.

The invention relates to the technical field of aluminum electrolyte recovery, in particular to a waste aluminum electrolyte resource utilization method. The waste aluminum electrolyte resource utilization method comprises the following steps that waste aluminum electrolyte and a reactant are subjected to a reaction in a closed container, a product obtained after the reaction is completed is washed in water, then first solid-liquid separation is carried out to obtain a solid, aluminum fluoride is obtained after drying, and aluminum fluoride is obtained after second solid-liquid separation is carried out. The reactant is selected from one or two of anhydrous aluminum chloride and polyaluminum chloride, and the reaction temperature is not lower than 200 DEG C. By utilizing the physical characteristic that the melting point of the reactant is higher than the boiling point, the reactant forms a solid phase-liquid phase-gas phase three-phase coexistence system in a closed space at the temperature higher than the melting point and the boiling point, so that the reactant can more efficiently perform molecular collision and mutual diffusion at an interface, thereby accelerating the reaction rate and improving the conversion rate.

The invention discloses an adsorbent / catalyst based on waste lithium battery recovery and a preparation method and application thereof, and the preparation method comprises the following steps: discharging and disassembling a waste lithium battery, mixing and ball-milling the obtained positive electrode material, metal scrap, PVC and negative electrode graphite material, adding water in the ball-milling process, and carrying out mechanochemical reaction; and after the ball milling is finished, carrying out water leaching treatment on a ball milling product, drying filter residues after the water leaching treatment, and calcining in an inert atmosphere at the calcining temperature of 350-900 DEG C for 0.5-4 hours to obtain the pollutant removal adsorbent / catalyst. The process flow is completed at normal temperature and normal pressure by adopting a mechanochemical method, high-temperature operation is not needed, and the problem of high energy consumption of pyrometallurgy is avoided. Meanwhile, strong acid or strong alkali is not used, no waste liquid or toxic gas is discharged, and compared with a traditional wet metallurgy / wet modified adsorbent / catalyst process, a resource recovery and material preparation technology which is more environmentally friendly and conforms to the green and low-carbon concept is achieved.

The invention belongs to the field of electrochemistry, and particularly relates to a method for electrochemical lithium extraction of a decommissioned lithium battery assisted by a pseudocapacitor cathode, which comprises the following steps: a) providing an anode electrode and a cathode electrode; the anode electrode is an anode electrode made of a recycled retired lithium battery anode material or an retired lithium battery anode plate; the cathode electrode contains a Prussian blue analogue, the Prussian blue analogue is prepared by mixing citrate, transition metal salt and cyanide in water for reaction, and the transition metal salt is one or more of cobalt salt, ferric salt, copper salt and nickel salt; and b) immersing the anode electrode and the cathode electrode into the electrolyte, and electrifying to carry out electrochemical lithium extraction. According to the method, a pseudocapacitance material with a lithium discharging characteristic is adopted as a cathode to replace a common metal pole plate or a carbon material, a pseudocapacitance reaction with a corrected electrode potential is adopted to replace a hydrogen evolution reaction on the cathode of an existing system, and finally, low-energy-consumption and high-selectivity recovery of lithium is realized.

The invention relates to the technical field of extraction and utilization of electrolytic aluminum lithium-containing waste, in particular to a method for selectively extracting lithium from electrolytic aluminum waste. The method comprises the following steps: (1) coarsely crushing the electrolytic aluminum waste; (2) calcining or combusting the electrolytic aluminum waste to remove carbon; (3) carrying out two-stage lithium leaching on the carbon-removed filter residues by controlling leaching conditions; (4) performing two-stage impurity removal on the lithium leachate; and (5) concentrating and denitrifying the impurity-removed liquid, precipitating lithium, carbonizing and crystallizing to prepare the battery-grade lithium carbonate. According to the method, after carbon in the electrolytic aluminum waste is removed through a calcination or combustion method, lithium in the waste aluminum slag is dissolved out into the leaching solution by controlling the leaching conditions, and aluminum, iron, sodium and most fluorine in the waste aluminum slag are not dissolved out and are left in the leaching slag. And performing simple impurity removal, concentration and denitration on the leachate to prepare the battery-grade lithium carbonate. The method is simple in process, low in reagent consumption and high in lithium extraction rate.

The invention provides a method and equipment for producing Li2CO3 based on coordinated roasting of lepidolite and spodumene. The method for producing Li2CO3 based on coordinated roasting of lepidolite and spodumene comprises the steps that S1, ore pretreatment is conducted, specifically, lepidolite and spodumene with the particle size smaller than 5 mm are evenly mixed according to the mass ratio of 1: (1-3), and the mixed ore is finely ground till the particle size is smaller than 75 microns; s2, additive mixing, wherein a composite additive is added into the mixed ore obtained after fine grinding and evenly mixed with the ore, and the composite additive is composed of fluoride, sulfate and a fluxing agent; and S3, coordinated roasting, wherein the mixed materials are fed into a rotary kiln to be roasted. According to the method for producing Li2CO3 based on coordinated roasting of the lepidolite and the spodumene, the lepidolite and the spodumene are roasted in a coordinated mode, the structural and chemical property differences of the lepidolite and the spodumene are utilized, advantage complementation is achieved, the overall extraction rate of lithium is increased, compared with a single lithium extraction technology, the lithium recovery rate can be increased by 10%-20%, and the waste residue generation amount is reduced.

The invention discloses a method for recycling a waste lithium battery positive electrode material, and relates to the technical field of lithium battery positive electrode materials. When the lithium battery positive electrode material is prepared, the waste lithium iron phosphate battery is discharged and then disassembled, a current collector is separated through cyclic soaking in cold and hot water, lithium ions are selectively leached through sulfuric acid-hydrogen peroxide after calcination, and the recycled lithium carbonate is obtained through recycling; preparing a carbonic acid ternary precursor by using a coprecipitation method; mixing the carbonic acid ternary precursor, recycled lithium carbonate, silicon monoxide, lithium fluoride and neodymium oxide, and performing secondary calcination to obtain a doped modified ternary positive electrode material; compounding and coating lanthanum, aluminum and zinc on the surface of the doped modified ternary positive electrode material by using a potassium-sodium alloy reduction method to prepare a coated modified ternary positive electrode material; and mixing the coated modified ternary positive electrode material with a conductive agent and a binder, and coating a carbon-coated aluminum foil with the mixture to prepare the lithium battery positive electrode material. The lithium battery positive electrode material prepared by the invention has high charge-discharge specific capacity, long cycle life and good rate capability.

The invention discloses a method for extracting lithium from gas field produced water with a high sodium-lithium ratio, and belongs to the technical field of chemical engineering. The mass ratio of sodium to lithium in the gas field produced water is (100-1000): 1, and the method comprises the following steps: S1, nanofiltration: carrying out nanofiltration on the gas field produced water, and intercepting divalent ions to obtain nanofiltration produced water and nanofiltration concentrated water; s2, adsorbing and extracting lithium, namely adjusting the pH value of the sodium-filtered produced water, treating the sodium-filtered produced water through a lithium-sodium adsorption and separation device filled with an adsorbent to realize sodium-lithium separation, and collecting the adsorbed lithium-extracted produced water; s3, desorption of lithium ions: eluting the adsorbent with an acid solution to desorb the lithium ions from the adsorbent, and collecting an eluent; s4, concentration: carrying out reverse osmosis treatment on the eluent, and treating the reverse osmosis concentrated solution through an electrodialysis device to obtain a concentrated lithium-containing concentrated solution; and S5, lithium precipitation: adjusting the pH value of the lithium-containing concentrated solution, adding a lithium precipitation agent, and crystallizing and precipitating lithium to obtain industrial-grade lithium carbonate. The process is simple, the lithium recovery rate during lithium precipitation can be effectively increased, and full-automatic continuous operation can be achieved.

The invention discloses a novel process for preparing battery-grade lithium carbonate from lithium precipitation mother liquor. The process comprises the following steps: mixing quick lime and the lithium precipitation mother liquor, adjusting alkali and removing fluorine; filtering calcium ions in the mixed solution, calcining the filtered calcium slag, and supplementing quick lime and carbon dioxide; mixing the obtained filtrate with an organic extraction agent for extraction; mixing the obtained loaded organic phase with pure water, and washing; carrying out reverse extraction on the obtained washed loaded organic phase; the obtained strip liquor is subjected to oil removal; decalcifying the deoiled strip liquor through resin; and pyrolyzing the obtained strip liquor, filtering and drying to obtain battery-grade lithium carbonate, and circulating the pyrolyzed liquor back to the strip-extraction section to supplement the water phase. According to the method, the mother liquor obtained after lithium precipitation of the lepidolite leaching solution serves as the raw material, the extraction-carbon dioxide reverse extraction process is carried out after alkali adjustment, the technological process is greatly shortened, the lithium recovery rate is increased, and the problems that energy consumption is large due to the fact that the lithium precipitation mother liquor is concentrated again or the grade of the lithium precipitation raw material solution is reduced due to the fact that the lithium precipitation mother liquor and the leaching solution are mixed are solved.

The invention relates to the technical field of battery negative electrode materials, in particular to a preparation method of a high-capacity silicon-carbon negative electrode material. According to the invention, the problems of low battery capacity and poor cycling stability of a battery assembled by using a silicon-carbon negative electrode material as a negative electrode material are solved. The preparation method comprises the following steps: controlling the particle size of iron nanoparticles, carrying out heating reaction to prepare pretreated silicon powder, cleaning, and modifying with a silane coupling agent to obtain nano silicon powder; carrying out microwave-assisted high-temperature calcination on the phenolic resin to obtain porous carbon; adding nano silicon powder and lithium carbonate into porous carbon, performing ball milling, adding titanium dioxide, performing ball milling again, and performing aluminum phosphate coating; then phenolic resin is used as a carbon source for carbon layer coating and high-temperature sintering, and the prepared silicon-carbon material is used for manufacturing a negative pole piece and assembling a battery; the battery capacity is improved by controlling the particle size of the nano micro powder and cooperating with porous carbon loading; and through microwave-assisted high-temperature calcination and the synergistic effect of the carbon coating layer and lithium carbonate, the cycle stability of the battery is improved, and the comprehensive performance of the battery is effectively improved.

The present invention provides a system and method for extracting lithium from salt lake brine and preparing battery-grade lithium carbonate. The system includes a coagulation and precipitation system, a filtration system, an adsorption and desorption system, a calcium and magnesium removal system, a boron removal system, a concentration system, an evaporation system, and a lithium precipitation system connected in sequence. The calcium and magnesium removal system includes a first-stage reverse osmosis concentration unit, a first-stage nanofiltration calcium and magnesium removal unit, a second-stage reverse osmosis concentration unit, a multi-stage nanofiltration calcium and magnesium removal unit, and a calcium and magnesium ion exchange unit connected in sequence. The boron removal system includes a first-stage nanofiltration boron removal unit, a multi-stage nanofiltration boron removal unit, and a boron ion exchange unit connected in sequence. After the lithium precipitation system, there are also a precision filtration system and a water washing and drying system connected in sequence. By adopting the process of the present invention, the lithium recovery rate is improved, and the product is battery-grade lithium carbonate, greatly improving the resource utilization and recovery rate of the lithium extraction system, reducing the amount of externally added water and the consumption of sodium carbonate in the process of the lithium precipitation system.

To provide an extractant for selectively extracting lithium salt, a method for recovering lithium salt, and a method for producing lithium salt.SOLUTION: A lithium salt extractant comprises at least one selected from a group consisting of a compound represented by a general formula (1) and a compound represented by the general formula (2) (where X1, X2, X3 and X4 independently represent an oxygen atom, a sulfur atom, a sulfinyl group, a sulfonyl group, a carbonyl group, or an imino group).SELECTED DRAWING: None

The invention discloses a method for extracting tantalum and niobium by roasting and melting tantalum and niobium concentrate through villiaumite after multiple times of acid leaching, which comprises the following steps: fully grinding the tantalum and niobium concentrate through a grinding machine, sieving, and fully mixing with concentrated acid according to a certain mass ratio for first acid leaching; filtering the mixed solution, and washing with pure water; mixing the filter residues with concentrated acid according to a certain mass ratio, carrying out secondary acid leaching, filtering, and washing the filter residues with pure water; drying the filter residue, and fully mixing with villiaumite according to a certain mass ratio; fully grinding the mixed solid roasting material by using a grinding machine; roasting and melting the materials; and leaching the roasted material with water or dilute acid, filtering after leaching is completed, and collecting filtrate. According to the method, most impurity ions can be effectively removed through secondary acid leaching impurity removal in the leaching process. And the fluorine salt roasting cost is low, the tantalum-niobium leaching effect is good, the tantalum-niobium leaching rate can reach 90% or above, and the comprehensive utilization rate of resources is high.

The invention provides a method for recovering all elements of a waste lithium iron phosphate battery positive electrode material. The method comprises the following steps: crushing the waste lithium iron phosphate positive electrode material, and performing nitrogen airflow crushing; adding hydrogen peroxide into the crushed material, performing ultrasonic treatment for multiple times, and performing microwave radiation treatment while performing ultrasonic treatment to obtain a mixture; diluted hydrochloric acid is added into the mixture, ultrasonic treatment is carried out multiple times while stirring is carried out, microwave radiation treatment and filtering are carried out while ultrasonic treatment is carried out, the pH value is adjusted to 3.5-4, then stirring and standing are carried out, a leaching material is obtained, filtering is carried out, and leaching residues and a leaching solution are obtained; the leaching residues are dried and roasted, and iron phosphate is obtained; concentrating the leachate, adjusting the pH value to 9.5-10, standing, filtering, and dropwise adding a sodium carbonate aqueous solution for reaction; and filtering and drying to obtain lithium carbonate. According to the recycling method, resource recycling of all elements can be achieved, the overall recycling rate of iron and lithium is high, and the purity of obtained lithium carbonate and iron phosphate is high.

The invention discloses a method for separating iron and lithium in a lithium iron phosphate iron salt leaching solution and recycling iron phosphate, and belongs to the technical field of waste lithium battery recycling. The method comprises the following steps: constructing a bis (2-ethylhexyl) phosphate and trioctyl decyl tertiary amine mixed extraction system for selective extraction of Fe < 3 + >, adopting phosphoric acid for reverse extraction, recycling phosphoric acid reverse extraction liquid, preparing iron phosphate and the like. According to the method, efficient enrichment of Fe < 3 + > and efficient elution of Fe < 3 + > from a loaded organic phase are realized. The purity of the raffinate Li solution is relatively high, so that the subsequent preparation of battery-grade lithium carbonate is facilitated. The strip liquor can be recycled for multiple times, an iron intermediate is precipitated through pH adjustment, and the FePO4 product can be finally prepared through washing, aging and high-temperature calcination. The method is high in extraction selectivity, recyclable in process and mild in operation condition, has good separation effect and resource utilization efficiency, and is suitable for popularization and application of a Fe / Li separation process in lithium battery recovery.

To provide a method which enables inexpensive production with a high yield of lithium hydroxide with a low amount of impurities such as sodium from lithium-containing water including a lithium ion and a chloride ion.SOLUTION: A production method of lithium hydroxide includes: a crystallizing step of crystallizing lithium hydroxide (LiOH) from lithium-containing water including a lithium ion and a chloride ion; a solid-liquid separation step of performing solid-liquid separation treatment of concentrated liquid including the LiOH to obtain the LiOH as a solid product and filtrate; a carbonation step of producing lithium carbonate from the filtrate by carbonation; a lithium carbonate recovery step of evaporating at least a part of ammonia from a mixed liquid obtained in the carbonation step and performing solid-liquid separation treatment of the resultant treated liquid to obtain lithium carbonate as a solid product; a lithium hydroxide production step of converting the obtained lithium carbonate into LiOH followed by solid-liquid separation treatment to obtain an aqueous LiOH solution (1) as a liquid component; and a recrystallizing step of crystallizing LiOH from the aqueous solution (1).SELECTED DRAWING: Figure 2

The invention provides lithium fluoride as well as a preparation method and application thereof. The mass content of carbonate in the lithium fluoride is less than or equal to 1000mg / kg; d10 of the lithium fluoride is smaller than or equal to 10 microns, D50 of the lithium fluoride is smaller than or equal to 20 microns, and the bulk density of the lithium fluoride is 0.9-1.2 g / cm < 3 >. The lithium fluoride provided by the invention has a specific size specification and relatively low carbonate impurity content, and the lithium fluoride is beneficial to preparation of electrolyte salt capable of improving the electrical performance of a battery.

The present invention relates to a composition comprising lithium carbonate obtained from black mass. The composition can be obtained by a process comprising (i) mixing black mass with a liquid to provide black mass slurry; (ii) converting lithium into a lithium salt in and removing graphite from the black mass slurry of step (i); (iii) separating dissolved lithium carbonate from solids in the black mass slurry of step (ii) to provide a lithium-enriched liquid fraction and a lithium-depleted solid fraction; optionally, reducing the lithium salt in the lithium-enriched liquid fraction of step (iii) to provide elementary lithium; (v) optionally, purifying the lithium salt in the lithium-enriched liquid fraction of step (iii) or the elementary lithium of step (iv); and (vi) optionally, solidifying the lithium salt of step (iii) or (v) or the elementary lithium of step (iv) or (v).

The present invention relates to a method for comprehensive recovery and treatment of lithium-containing overhaul slag and carbon slag. The preparation process is: firstly, the overhaul slag or carbon slag is ball-milled into powder, and the fineness is greater than 200 meshes; sodium hydroxide solution is prepared, and the concentration is 3%-15%, and the ground powder is added to the sodium hydroxide solution, and the solid content is controlled to be 3%-10%; stirring at 60℃-90℃ for 2h-5h; filtering to obtain filter residue and filtrate, and carbon dioxide is introduced into the filtrate under stirring conditions for carbonization to obtain cryolite slurry, and cryolite and sodium carbonate solution are obtained by filtration and separation; the filter residue is subjected to secondary alkaline leaching with calcium hydroxide slurry, and the filter residue and filtrate are obtained by filtration and separation, and the filter residue is sent to a cement plant as a raw material for making cement, and the filtrate is added to the above sodium carbonate solution to precipitate lithium to obtain lithium carbonate, so as to realize the comprehensive recovery and utilization of lithium, sodium, aluminum and fluorine in the overhaul slag / carbon slag. The comprehensive recovery rates of lithium and fluorine are 85% and 80% respectively.

The invention relates to a method for recycling aluminum, iron and lithium from waste lithium iron phosphate batteries. The method comprises the following steps: firstly, separating a positive electrode material of a waste battery cell, removing a binder through high-temperature treatment, adding the positive electrode material into a NaOH solution and a viscous liquid cosolvent, finally stirring and dissolving, neutralizing and adjusting the pH value through sulfuric acid, and precipitating and recovering aluminum; then sulfuric acid is matched with hydrogen peroxide, residual filter residues are stirred and dissolved, the pH value is adjusted in multiple steps, iron and lithium are precipitated respectively, and Fe (OH) 3 and Li2CO3 precipitates are obtained in sequence; the viscous liquid cosolvent disclosed by the invention is prepared from 1-aminoethyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imine salt and boric acid powder; the recovery rate of aluminum, lithium and iron is high, the recovery cost is low, and the economic value is high.