203 results about "Lithium sulphate" patented technology

The invention discloses high-purity lithium sulfide as well as a preparation method and application thereof. The preparation method comprises the step that lithium hydride, lithium hydroxide and a sulfur source are subjected to a heating reaction in a dry inert atmosphere, and the high-purity lithium sulfide is obtained. The molar ratio of lithium hydride to lithium hydroxide is X: (10-X), and X is 1-6. The invention also discloses the prepared high-purity lithium sulfide and application of the high-purity lithium sulfide in preparation of sulfide solid electrolyte. Lithium hydroxide and lithium hydride are mixed to serve as a lithium source in lithium sulfide preparation, the lithium hydroxide quickly and uniformly reaches the reaction temperature by means of the characteristic that the lithium hydride reacts with a sulfur source to release heat and produce gas, the lithium hydride reacts to produce gas, meanwhile, discharging of product water vapor is facilitated, and oxygen in the environment is isolated; and hardening and generation of a side reaction product lithium sulfate are prevented, the conversion rate of lithium hydroxide to lithium sulfide is improved, and the raw material and process cost for preparing lithium sulfide is remarkably reduced.

The invention relates to the technical field of preparation of lithium sulfide, in particular to a method for preparing lithium sulfide through hydrogen reduction of lithium sulfate. According to the specific technical scheme, the method for preparing the lithium sulfide by reducing the lithium sulfate through the hydrogen comprises the steps that the lithium sulfate is smashed to be micron-sized and then fed into a fluidized bed reactor, then high-purity hydrogen preheated to 850 DEG C is introduced into the fluidized bed reactor from the bottom of the fluidized bed reactor, the reaction temperature is controlled to be 850 + / -20 DEG C, and the reaction time is controlled to be 5-10 min. The hydrogen reduction method is relatively low in reaction temperature (700-900 DEG C), hydrogen is used as a clean reducing agent, a reaction byproduct is only water, and the problems of insufficient purity, high energy consumption, serious environmental pollution and the like in a traditional lithium sulfide preparation method can be avoided. The introduction of the fluidized bed technology can greatly enhance the gas-solid phase heat and mass transfer efficiency, realizes the continuity and automation of the process, and is an important path for realizing the industrialization of the reaction.

The invention relates to the technical field of battery raw materials, in particular to a preparation method of lithium sulfide powder, the lithium sulfide powder and application, and the preparation method comprises the following steps: uniformly mixing lithium sulfate and a carbon source according to a preset proportion to obtain a first mixture; performing first heat treatment on the first mixture in inert gas to obtain a second mixture; and performing second heat treatment on the second mixture in reducing gas to obtain the lithium sulfide powder. The product obtained by the preparation method disclosed by the invention is the lithium sulfide powder, and the obtained lithium sulfide powder has the advantages of less oxygen and carbon impurities, higher purity and high reaction activity, and meets the synthesis requirements of the electrolyte; according to the preparation method, in the process of preparing lithium sulfide, toxic gas and organic solvent are not used, the reaction temperature is low, the energy consumption is low, the requirement on production equipment is low, the process is simple, the cost is low, harmful gas emission is avoided, safety and environment friendliness are achieved, and industrialization is easy to achieve.

The application discloses a method for preparing high-purity battery-grade lithium sulfide by reducing lithium sulfate with a reducing gas. The specific steps are as follows: raw material lithium sulfate and inert wave-absorbing substances are mixed, uniformly mechanically ball-milled, tablet-pressed, sieved, put into a microwave reactor, and then a reducing gas is introduced for microwave heating reaction; after cooling to room temperature, the mixture is discharged into another reactor, ethanol is added for dissolution, mechanical stirring is carried out, and then standing and filtration are performed; the inert wave-absorbing substances are recycled and reused; an ethanol solution of dissolved lithium sulfide is obtained; crude lithium sulfide is obtained by heating and distillation; after freeze-drying, the crude lithium sulfide is heated and secondarily calcined in a rotary furnace under the protection of inert gas, and finally battery-grade high-purity lithium sulfide is obtained. By mixing the inert wave-absorbing substances with the lithium sulfate and heating by the microwave method, the contact surface of the lithium sulfate and the gas can be improved, and in addition, the internal heating method can be used to avoid the lithium sulfide formed on the outer surface from wrapping the raw material lithium sulfate, so as to affect the hydrogen reduction efficiency.

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

The invention discloses electronic-grade lithium sulfide as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing lithium sulfate with hydrogen under a vacuum condition, and carrying out a reduction reaction to prepare the electronic-grade lithium sulfide. According to the preparation method of the electronic-grade lithium sulfide, lithium sulfate is reduced through hydrogen, no waste gas or waste water is generated in the process, environment friendliness is achieved, unreacted hydrogen and water vapor return to the hydrogen storage tank, hydrogen can be reused, the water vapor settles to the bottom of the tank to be recycled after being condensed, the technological process is short, and the product purity is high; the method is suitable for large-scale popularization and application.

The invention discloses a method for separating and recycling phosphorus, iron and lithium in battery black powder, and relates to the technical field of battery recycling. The method comprises the following steps: carrying out acid leaching on battery black powder to obtain a battery black powder leaching solution and filter residues; an oxidizing agent is added into the battery black powder leaching solution, the pH of the solution is adjusted to 1.8-2.5, solid-liquid separation is conducted after the reaction is completed, and iron phosphate sediment and a lithium-containing solution are obtained; adjusting the pH value of the lithium-containing solution to 10-12, and carrying out solid-liquid separation after the reaction is completed to obtain a metal precipitate and a lithium sulfate solution; dissolving the iron phosphate precipitate in a sulfuric acid solution, adding a reducing agent to reduce ferric iron into ferrous iron, separating out ferrous sulfate by adopting an alcohol precipitation method or an ammonium sulfate crystallization method, and performing solid-liquid separation after the reaction is completed to obtain ferrous sulfate precipitate or ammonium ferrous sulfate crystals and mother liquor; and evaporating and concentrating the mother liquor, and extracting to obtain a phosphoric acid solution. According to the method, the three elements of phosphorus, iron and lithium in the battery black powder can be recycled, and the environmental problem caused by stacking of the lithium extraction slag can be avoided.

The utility model discloses a liquid-phase synthesis system of lithium sulfide. Comprising a first lithium sulfate dissolving device, a first barium sulfide dissolving device, a chemical combination reaction device, a first separation device and a second separation device, the liquid phase after-treatment unit is used for concentrating, purifying and drying the liquid phase to obtain lithium sulfide, and the solid phase after-treatment unit is used for washing and drying the solid phase to obtain barium sulfate; the first lithium sulfate dissolving device and the first barium sulfide dissolving device are both connected with a raw material inlet of the combination reaction device; and a reaction product outlet of the combination reaction device is connected with the first separation device. The liquid-phase synthesis system of the lithium sulfide has the advantages that products are easy to separate, the purity of the lithium sulfide products is high, the liquid-phase synthesis system of the lithium sulfide is very suitable for industrial-scale production, and the produced high-purity anhydrous lithium sulfide is very suitable for solid-state battery anode materials and has huge potential economic benefits.

The invention discloses a method for preparing high-purity lithium sulfide from a lithium sulfate mother liquor, which comprises the following steps: preparing a lithium sulfate concentrated liquor: adding 98% concentrated sulfuric acid into the lithium sulfate mother liquor to adjust the pH value, adjusting the pH value to 6-7, carrying out precise filtration to filter out possible impurities to obtain a filtrate, introducing the filtrate into an MVR evaporation system, and concentrating the mother liquor to obtain a concentrated liquor, performing freezing crystallization on the concentrated solution by using a cooling crystallizer, and then performing centrifugal separation under the action of a centrifugal machine to obtain solid slag which is mirabilite and a solution which is lithium sulfate concentrated solution; and preparing crude lithium sulfide: performing evaporative crystallization on the obtained lithium sulfate concentrated solution, adding pure water for slurrying, and performing centrifugal filtration and cleaning for 2-3 times. The impurity content is effectively controlled through a multi-stage purification process, the Li2S product with the purity larger than or equal to 99.95% is finally obtained, the key technical problem of direct conversion from a liquid battery recycling material to a solid battery positive electrode raw material is solved, and core material support is provided for lithium battery industry closed loop and industrial product iteration.

The invention discloses a lithium dihydrogen phosphate preparation method, which comprises: S1, mixing a refined lithium sulfate solution with an extraction agent solution, and carrying out standing layering to obtain an upper layer solution; s2, mixing the upper-layer solution with a detergent, washing, and separating to obtain a washing solution; s3, mixing the washing liquid with a phosphoric acid solution, and standing for layering to obtain a lower-layer solution; s4, mixing the lower-layer solution with a component regulator; and carrying out solid-liquid separation. An extracting agent in the extracting agent solution comprises at least one of benzoyl trifluoroacetone, trialkyl phosphine oxide and sulfonated calixarene. The specific extraction agent efficiently selects lithium ions to separate impurities, lithium dihydrogen phosphate is obtained through direct reverse extraction after washing, lithium dihydrogen phosphate does not need to be converted into other lithium products to prepare lithium dihydrogen phosphate, and the process production period is shortened. In addition, lithium dihydrogen phosphate is prepared through washing and reverse extraction after impurities are efficiently selected and separated through an extraction agent; the purity is high; the battery grade lithium dihydrogen phosphate can be obtained.

The invention discloses a quick-hardening early-strength concrete mineral additive and a preparation method thereof, and belongs to the technical field of building materials. The additive comprises the following components in parts by weight: 50-75 parts of a mineral active material (compounded by silica fume, slag powder and metakaolin), 15-30 parts of a composite activator (sodium silicate, lithium sulfate and triethanolamine synergistically), 5-10 parts of a sustained-release microcapsule (calcium sulphoaluminate coated with nano-silica) and 2-5 parts of an auxiliary thickening agent (compounded by HPMC and a water reducing agent). The preparation method comprises the steps of mineral activation, excitant reaction and mixing of the microcapsule and the thickening agent. After the additive is doped into concrete, the 3h compressive strength is greater than or equal to 15MPa, the initial setting time is less than or equal to 5min, and the additive has low resilience (less than or equal to 13%), high durability (impermeability is greater than or equal to P11) and environmental adaptability (-5 DEG C strength fluctuation ratio is less than or equal to 9%). And compared with the prior art, the cost is reduced by 40%, and the method has remarkable economic and social benefits.

The invention discloses lithium sulfide and a preparation method thereof. The preparation method comprises the following steps: (1) carrying out ball-milling mixing on iron powder, sodium sulfide and lithium sulfate in a first inert atmosphere to obtain a mixture; (2) calcining the mixture in a second inert atmosphere for the first time to obtain a reaction material; (3) stirring and washing the reaction material with an alcohol solvent in a third inert atmosphere, filtering to obtain filtrate and a filter cake, performing reduced pressure distillation on the filtrate to obtain a lithium sulfide crude product, washing the filter cake with deionized water, and filtering to obtain a solid by-product; and (4) carrying out secondary calcination on the lithium sulfide crude product in a fourth inert atmosphere to obtain lithium sulfide. The preparation method provided by the invention has the advantages of few synthesis steps, simple product purification and environmental protection.

The invention discloses a method for directly preparing high-purity Li2S by utilizing carbothermal reduction, which comprises the following steps: ball-milling and mixing Li2SO4.H2O and a carbon source, and carrying out first-step calcination in an air atmosphere at the calcination temperature of 450-550 DEG C to obtain a first-step calcination product; carrying out ball-milling mixing on the first-step calcined product and sublimed sulfur powder, tabletting, and carrying out second-step calcination at the calcination temperature of 700-800 DEG C under the protection of inert gas to obtain a second-step calcined product; and continuously performing third-step calcination on the second-step calcination product under the protection of inert gas at the calcination temperature of 850-950 DEG C to obtain the product Li2S. Lithium sulfate and a high-purity carbon source are adopted as main raw materials, sublimed sulfur powder is introduced in the second-step calcination process to inhibit generation of Li2O, after the carbon source is consumed in the second-step calcination process, a mixture of lithium sulfide and residual lithium sulfate is obtained, the temperature continues to rise, third-step calcination is conducted, the residual lithium sulfate is molten, volatilized and removed, and the lithium sulfide is obtained. And discharging the mixture out of the tubular furnace along with the gas flow of the inert gas to obtain high-purity lithium sulfide.

The invention discloses a preparation method of high-purity lithium sulfide based on a carbon reduction method, and belongs to the technical field of material preparation. Comprising the following steps: S1, mixing anhydrous lithium sulfate with a reducing agent, and adding absolute ethyl alcohol as a solvent, S2, drying a material subjected to wet grinding, removing the absolute ethyl alcohol solvent and water, and transferring the material into a tubular furnace or an atmosphere sintering furnace to obtain a dried material; s3, the environment temperature in the furnace is increased to 600-800 DEG C at the heating rate of 5-12 DEG C / min, heat preservation is conducted for 30-60 min, and a reduction reaction is conducted; s4, after a reduction reaction product is cooled to the room temperature, adding absolute ethyl alcohol, stirring until the absolute ethyl alcohol is fully dissolved, completing solid-liquid separation through a suction filtration device, collecting filtrate and distilling; and S5, drying the distilled product to obtain the high-purity lithium sulfide. By accurately controlling the raw material purity, the reaction parameters and the purification process, the product purity is greater than or equal to 99.5%, the yield is greater than or equal to 89%, and the high-performance application requirements of solid-state batteries and the like are completely met; the method is simple in process steps, moderate in equipment requirements and suitable for large-scale industrial production.

The invention discloses a method for preparing high-purity lithium sulfide by recycling a waste lithium ion battery positive electrode material. The method comprises the following steps: selectively leaching lithium from lithium manganate, lithium iron phosphate and a waste ternary positive electrode material; the lithium-rich lixivium is subjected to precipitation, purification and impurity removal, and a high-purity lithium sulfate refined solution is obtained; drying the high-purity lithium sulfate refined liquid to obtain anhydrous lithium sulfate; mixing and ball-milling anhydrous lithium sulfate and carbon powder to obtain a first precursor; carrying out high-temperature calcination on the first precursor in an inert gas atmosphere to obtain a second lithium sulfide precursor; dissolving, evaporating and crystallizing the second precursor to obtain a lithium sulfide intermediate; and crushing the lithium sulfide intermediate, and carrying out secondary sintering to obtain the high-purity lithium sulfide. The preparation method is simple, lithium is selectively extracted from the positive electrode material of the waste lithium ion battery, the loss of lithium ions is reduced, the preparation cost of lithium sulfate is reduced by adopting the high-purity lithium sulfate filtrate, the method is simple in process, and the purity of the obtained lithium sulfide can reach 99.5% or above.

The invention belongs to the technical field of building materials, and provides an early-strength cement-based grouting material and a preparation method thereof.The early-strength cement-based grouting material is prepared from, by weight, 500-600 parts of sulphoaluminate cement, 200-300 parts of Portland cement, 40-100 parts of lithium slag, 1-3 parts of a coagulant, 0.5-1 part of an early strength agent, 5-8 parts of a water reducing agent, 0.5-2.5 parts of a thickening agent, 0.3-0.9 part of a defoaming agent and 260-310 parts of water; the coagulant is sodium metaaluminate and / or potassium metaaluminate; the early strength agent is selected from one or more than two of lithium carbonate, lithium sulfate, calcium formate, calcium acetate, calcium propionate, calcium butyrate and nano silicon dioxide. According to the technical scheme, the problems of poor dispersion resistance and low early strength of a cement-based grouting material in a flowing water environment in the prior art are solved.

The utility model relates to the technical field of coating devices, and discloses separation equipment for lithium sulfate solution production, which comprises a separation equipment body and a feed port fixedly connected to the top of the separation equipment body, and further comprises a discharge pipe fixedly connected to the bottom of the separation equipment body, a control chamber is fixedly connected to the bottom of the reaction chamber and communicates with the feeding port, a sealing plate is fixedly connected to the interior of the control chamber, and a quantity control mechanism is further arranged in the separation equipment body. Through the arrangement of the reaction chamber, the control chamber and the sealing plate, the effect of conveniently controlling the quantity of a lithium sulfate solution by a worker is achieved, the subsequent separation effect is improved, and the problem that in the using process of existing separation equipment, the lithium sulfate solution is often directly poured into a separation net at a time, and the separation efficiency is affected is solved. And the problem that the separation effect is poor due to the fact that too much liquid is poured at a time is possibly solved.

A method for producing lithium sulfide according to the present invention is characterized by having a raw material mixing step (S1) in which lithium sulfate and a carbon material are mixed to form a mixed raw material, and a thermal reduction step (S2) in which the mixed raw material is heat-treated in a non-oxidizing atmosphere and the lithium sulfate is thermally reduced to generate lithium sulfide, the method also being characterized in that a carbon powder having a specific surface area measured by the BET method of 55 m2 / g or greater is used as the carbon material. A method for producing a sulfide-based solid electrolyte according to the present invention is characterized in that lithium sulfide produced through the method for producing lithium sulfide according to the present invention is used as a raw material.

The utility model discloses an evaporation and concentration system suitable for lithium sulfate purification, which is characterized in that an outlet of a raw material tank is sequentially connected with a cold side of a condensate water preheater and a cold side of a non-condensable steam preheater through an outlet of a feeding pump, and then is connected with a tube pass inlet of a heater together with an outlet pipeline of a material circulating pump; a tube pass outlet of the heater is connected with a material inlet of the integrated separator, and a material outlet of the separator is connected with an inlet of the material circulating pump; a secondary steam outlet of the integrated separator is connected with an inlet of a steam compressor through a scrubber tower, and a compressed steam pipe is connected with a shell pass steam inlet of a heater; a shell pass condensed water outlet of the heater is connected with an inlet of a condensed water tank; an outlet of the condensed water tank is connected with a hot side of the condensed water preheater through a condensed water pump; a shell pass extraction opening of the heater is connected with the hot side of the non-condensable steam preheater through a non-condensable gas conveying pipe, and a hot side outlet of the condenser is connected with a vacuumizing system. The system is high in evaporation efficiency and low in operation cost and equipment investment.

The present disclosure is directed to systems and methods of leaching lithium sources using sodium sulfate. The process can include mixing a lithium source, a first sodium sulfate, and lithium hydroxide in a reactor and leaching the lithium source in the mixture in the reactor to form residual solids and a lithium sulfate leachate.

The invention discloses a lead-lithium battery negative electrode material composite formula and a processing technology, and belongs to the technical field of lead-lithium batteries, the lead-lithium battery negative electrode material composite formula comprises the following components by weight: 80-90 parts of a high-entropy lead powder composite material, 2-5 parts of a novel composite expanding agent, 1-3 parts of a conductive reinforcing agent, 5-8 parts of a lithium sulfate-MOF electrolyte with a concentration of 0.5-1.5 mol / L, and 3-6 parts of a binder, the negative electrode material has the advantages of being capable of effectively dispersing the additive and avoiding overgrowth of lead sulfate crystals, and the problems that an existing negative electrode material composite formula of the lead-lithium battery cannot avoid overgrowth of the lead sulfate crystals and an existing processing technology cannot ensure uniform dispersion of the additive, and then the discharge performance and the overall service life of the lead-lithium battery are affected are solved.

The present invention relates to a method for recovering lithium from a lithium-containing waste liquid, the method including the steps of: filtering a cathode material wash solution to separate solid metals contained in the basic waste liquid; adding sulfuric acid to the cathode material wash solution from which the solid metals have been filtered to acidify it and convert lithium carbonate or lithium hydroxide into lithium sulfate; concentrating the wash solution converted into lithium sulfate to obtain a high-concentration lithium sulfate solution; and mixing the high-concentration lithium sulfate solution with a resultant product obtained by leaching from an ore.

The invention provides a method for preparing high-purity lithium sulfate from a lithium-sodium mixed solution. The method comprises the following steps: providing a lithium-sodium mixed sulfate solution; the method comprises the following steps: based on a Li2SO4-Na2SO4-H2O ternary system phase diagram, evaporating and concentrating a lithium-sodium mixed sulfate solution to be saturated, and then freezing and denitrifying to obtain a denitrified solution; evaporating the denitrated solution to a co-saturation point of lithium-sodium mixed sulfate, carrying out lithium precipitation, and separating to obtain a lithium precipitation mother solution and a lithium sulfate monohydrate crude product; purifying the lithium sulfate monohydrate crude product to obtain a high-purity lithium sulfate product; freezing and crystallizing the lithium precipitation mother solution, and separating to obtain a lithium-sodium mixed sulfate hydrate and a frozen solution; the lithium-sodium mixed sulfate hydrate is returned to the lithium-sodium mixed sulfate solution, and the frozen liquid is returned to the denitrated liquid. According to the method, the process is simplified, the lithium recovery rate is increased, cost reduction and efficiency improvement are achieved, material recycling can be achieved in the whole process, and the development prospect is good.

This invention provides a method and apparatus for lithium recovery from a high-sodium, low-lithium solution via cryogenic sodium precipitation and targeted extraction. The method comprises the following steps: S1, weighing sodium sulfate and lithium sulfate samples, dissolving them in deionized water to prepare a high-sodium, low-lithium solution; S2, determining the lithium and sodium ion content of the high-sodium, low-lithium solution using ICP-MS and atomic absorption spectroscopy; S3, freezing the high-sodium, low-lithium solution prepared in step S1 in a circulating freezer to obtain a solid-liquid mixture. The method and apparatus provided by this invention achieve low lithium carryover during sodium precipitation from a high-sodium, low-lithium solution, further realizing high-efficiency lithium resource recovery. Compared with traditional processes, the lithium carryover rate during sodium precipitation can be reduced to 0.2%, reducing energy consumption and operational difficulty while improving lithium recovery rate, making it suitable for industrial production.

A method for producing battery-grade lithium dihydrogen phosphate using lithium-containing brine includes the following steps: (1) adding sodium hydroxide solution to lithium-containing mother liquor, adding the mixed solution to sodium dihydrogen phosphate solution, maintaining the pH of the system at 9-11, reacting, separating the solid and liquid phases to obtain lithium phosphate precipitate and mother liquor; (2) adjusting the slurry, adding concentrated sulfuric acid to react, separating the solid and liquid phases to obtain a mixed solution of liquid-phase lithium dihydrogen phosphate and lithium sulfate; (3) vacuum cooling and crystallization separation to obtain lithium dihydrogen phosphate crystals. This invention achieves efficient recovery of lithium ions from low-concentration lithium-containing brine, eliminating the need for conventional processes such as electrodialysis and MVR for further concentration of lithium-containing mother liquor. It also avoids the use of phosphoric acid in the acidification process, saving raw material costs, reducing the amount of water added in the acidification process, and reducing energy consumption in the crystallization separation process. The resulting battery-grade lithium dihydrogen phosphate is of stable quality, uniformly distributed, and bright white in color, suitable for preparing lithium-ion battery cathode materials, and has a low cost.

The application discloses a method for preparing battery-grade lithium phosphate based on step-by-step precipitation and double washing and application thereof. The method takes crude lithium sulfate as raw material, and through an integrated process of step-by-step precipitation and double washing, the problem of the wrapping of impurity sodium ions and sulfate in the lithium precipitation process of the crude lithium sulfate is solved, and the production cost of the lithium phosphate is reduced, so that the method is suitable for the industrialized production of lithium ion battery positive material precursors. The application mainly controls the impurity content from two aspects. Through step-by-step precipitation and crystal type induced generation, the wrapping of impurities in the product crystal grains can be reduced, and the double washing scheme can remove the residual impurities in the crystal grain gaps. The purpose of the crystal type induced generation is to guide the generation of large crystals and reduce the specific surface area, so that the Na adsorption amount is reduced.

The invention discloses a lithium source impurity removal method, lithium phosphate and a preparation method thereof, and belongs to the technical field of battery materials. The invention solves the problem of how to provide a method for preparing high-purity lithium phosphate from a lithium source in lithium ore. The method comprises the step of removing impurities from a lithium source, and specifically comprises the following steps: roasting lithium ore, and leaching a product obtained after roasting to obtain a lithium sulfate solution; adding one or more of ammonia water, ammonia gas or liquid ammonia into the lithium sulfate solution to adjust the pH value to 8-11, and then filtering to obtain primary purified mother liquor; adding monoammonium phosphate or / and diammonium phosphate into the primary purified mother liquor, adjusting the pH value to 8-11 again, reacting under the stirring condition, and filtering to obtain secondary purified mother liquor; and adding EDTA (Ethylene Diamine Tetraacetic Acid) into the secondary purified mother liquor to obtain the lithium sulfate purified mother liquor. And adding one or more of ammonia water, ammonia gas or liquid ammonia into the monoammonium phosphate solution to adjust the pH value to 8-11, and adding the purified lithium sulfate mother liquor into the monoammonium phosphate solution to obtain the high-purity lithium phosphate.

A process for preparing metal oxide comprising (i) at least one metal chosen from nickel and cobalt and optionally (ii) at least one metal chosen from manganese, lithium and aluminum. The process comprising:reacting a metal sulfate comprising (i) at least one metal chosen from nickel and cobalt and optionally (ii) at least one metal chosen from manganese, lithium and aluminum with lithium hydroxide and optionally a chelating agent to obtain a solid comprising a metal hydroxide comprising (i) at least one metal chosen from nickel and cobalt and optionally (ii) at least one metal chosen from manganese, lithium and aluminum, and a liquid comprising lithium sulfate, the metal sulfate comprising (i) at least one metal chosen from nickel and cobalt and optionally (ii) at least one metal chosen from manganese, lithium and aluminum;separating the liquid and the solid from one another to obtain the metal hydroxide;submitting the liquid comprising lithium sulfate to an electromembrane process for converting the lithium sulfate into lithium hydroxide; andreusing at least a first portion of said lithium hydroxide obtained by the electromembrane process for reacting with the metal sulfate;reacting at least a second portion of said lithium hydroxide obtained by the electromembrane process with the obtained metal hydroxide to obtain a mixture of metal hydroxides; androasting said mixture of metal hydroxides to obtain the metal oxide.

The invention relates to the technical field of piping inverted filter bricks, in particular to a cement-based piping inverted filter brick and a preparation method thereof. Which comprises Portland cement, mineral powder, fly ash, silica fume, recycled aggregate and an additive. The method comprises the following steps: mixing the recycled aggregate, the Portland cement, the mineral powder and the silica fume; sequentially adding latex powder, a water reducing agent, sodium citrate, tartaric acid, lithium sulfate or lithium carbonate, cellulose ether, a defoaming agent and a dispersing wetting agent, and uniformly stirring; after being uniformly stirred to prepare mortar, the mortar and tap water are uniformly stirred and mixed at a high speed, and the addition amount of the water is 8-10% of the total mass of the mortar; the cement-based piping anti-filtration mortar is poured into a mold to prepare the high-strength piping anti-filtration brick, and the high-strength piping anti-filtration brick is used after being cured to a specified age after being demolded, so that the effects of increasing the manufacturing speed of the piping anti-filtration well, reusing the materials and not preparing the materials of the piping anti-filtration well are realized, and the manpower and the time are saved.

The application belongs to the technical field of lithium ion battery negative electrode materials, and particularly relates to a MXene two-dimensional material, a graphite negative electrode material and a preparation method of the MXene two-dimensional material, the preparation method of the MXene two-dimensional material being as follows: lithium sulfate solution is added into a MXene dispersion liquid, stirred uniformly, vacuum dried, calcined at 300-500 DEG C, and the MXene two-dimensional material is obtained; and the application can effectively improve lithium ion conductivity and improve the performance of a battery.