107 results about "Oxalate salt" patented technology

Method for preparing a catalyst composition comprising indium bismuth alloy which method comprises (a) combining at least an indium containing salt, a bismuth containing salt and an oxalate salt in a liquid to obtain a precursor mixture; (b) combining the precursor mixture with a reducing agent to obtain a suspension comprising the catalyst composition; and (c) separating the catalyst composition from the suspension, wherein a support material is either added to the precursor mixture or to the reducing agent, and to catalyst composition comprising indium bismuth alloy obtainable by this method.

The invention belongs to the technical field of medicine crystals, and relates to cordycepin-oxalate as well as a preparation method and application thereof. The invention relates to a preparation method of cordycepin-oxalate. The preparation method comprises the following steps: (1) physical mixing: sufficiently and uniformly mixing oxalic acid and cordycepin-crystal form II crystals; (2) liquid auxiliary grinding: adding an auxiliary agent, and continuously grinding to obtain a solid mixture; and (3) drying the solid mixture to obtain the cordycepin-oxalate. According to the method, the cordycepin-oxalic acid eutectic salt is prepared for the first time, the dissolution rate of the cordycepin-oxalic acid eutectic salt is obviously lower than the dissolution rate of cordycepin reported in the prior art, and the cordycepin-oxalic acid eutectic salt has extremely high potential medicinal application value. The cordycepin-oxalic acid eutectic salt has important technical innovation and market application potential due to the slow release effect.

The invention discloses a method and device for continuously preparing lithium difluoro (oxalato) borate and a lithium difluoro (oxalato) borate solution, and belongs to the technical field of electrolyte salt synthesis, the method comprises the following steps: continuously pumping chlorosilane and a first mixed solution formed by oxalate and an ester solvent into a first dynamic microchannel reactor, and carrying out a first reaction to obtain a reaction product, wherein the mass flow ratio of the first mixed solution to the chlorosilane is (4-10): 1; continuously pumping the reaction product into a second dynamic micro-channel reactor, continuously pumping a second mixed solution formed by lithium tetrafluoroborate and an ester solvent into the second dynamic micro-channel reactor, and carrying out a second reaction at a temperature of 20-70 DEG C and a rotating speed of 200-400 r / min to obtain a mixed reaction solution; and separating a reaction product in the mixed reaction liquid to obtain the lithium bis (fluoro) oxalato borate. According to the method for continuously preparing the lithium difluoro (oxalato) borate, the continuous production of the lithium difluoro (oxalato) borate can be realized, and the quality of the lithium difluoro (oxalato) borate is high.

The invention discloses a method for recycling retired lithium iron phosphate batteries and producing iron phosphate. The method comprises the following steps: adding alkali into a mixed solution containing Fe < 3 + >, Li < + > and PO4 < 3-> obtained after acid leaching to adjust the pH value, separating out an iron phosphate solid, reacting iron phosphate with acid and a reducing agent, and then reacting with oxalate, so that the iron element is mainly recovered in the form of ferrous iron; reacting the lithium salt solution by a method of adding an alkaline carbonate solution or introducing carbon dioxide gas to generate lithium carbonate precipitate, and recovering lithium carbonate; the recycled ferrous chloride can be used for preparing a ferric iron solution, and the ferric iron solution is directly used for producing iron phosphate, so that the iron element is regenerated and reused in the lithium iron phosphate.

A preparation method of N '-((2S, 3S)-2-(benzyloxy) pent-3-yl) formylhydrazine oxalate enzyme belongs to the field of medical intermediates, and comprises the following steps: step 1, preparing a buffer solution of a compound enzyme preparation; step 2, adding (2S)-2-benzyloxy-3-pentanone into a solvent A, and then adding a buffer solution of the compound enzyme preparation for reaction; 3, filtering, and carrying out an activation reaction on the filtrate; 4, filtering, removing the solvent, adding the obtained solid into a solvent B, and then adding formylhydrazine for reaction; 5, filtering, removing the solvent, adding the obtained solid into a solvent C, and then adding oxalic acid for reaction; and 6, drying the solid obtained by filtering to obtain the N '-((2S, 3S)-2-(benzyloxy) pent-3-yl) formylhydrazine oxalate. According to the method, the yield of the N '-((2S, 3S)-2-(benzyloxy) pent-3-yl) formylhydrazine oxalate can be increased, and the production cost is effectively reduced.

The invention relates to the field of hydrometallurgy, and discloses a method for converting hafnium oxalate feed liquid into hafnium sulfate feed liquid, which comprises the following steps: adding a sulfuric acid solution and an oxidizing agent into the hafnium oxalate feed liquid, and reacting at a certain temperature to obtain the hafnium sulfate feed liquid. Oxidants used in the method are preferably hydrogen peroxide and ozone, other impurity ions are not introduced, and the purity of the product is not influenced at all. Oxidation products are H2O and CO2 and are basically free of pollution to the environment. The process of evaporation, filtration, calcination, redissolution and the like of a traditional evaporation method and an alkali precipitation-redissolution method is not needed, the operation is simple, the efficiency is high, the cost is low, and the operability is high. The method for adding the sulfuric acid solution and the oxidizing agent into the oxalate feed liquid is also suitable for converting oxalate solutions of other metal ions into sulfate solutions, including but not limited to zirconium oxalate, titanium oxalate, thorium oxalate, scandium oxalate, niobium oxalate, tantalum oxalate, vanadium oxalate, cobalt oxalate, cesium oxalate and rubidium oxalate.

The present invention discloses a Prussian blue-based sodium-ion battery positive electrode material, a preparation method, and applications thereof. The method comprises: mixing sodium ferrocyanide, oxalate, and a non-aqueous solvent, subjecting the mixture to a ball-milling reaction, and washing the product after the ball-milling reaction to remove unreacted raw materials and a portion of sodium oxalate generated by the reaction, thereby obtaining the Prussian blue-based sodium-ion battery positive electrode material. The present invention can synthesize Prussian blue-based compounds with low defects and low interstitial water molecule content, thereby improving the sodium storage performance and capacity utilization of such materials; it also reduces the probability of side reactions in the electrolyte causing cell bloating. In addition, the use of oxalate-based raw materials can also generate a sodium oxalate-based positive electrode sodium supplement during the synthesis of the Prussian blue-based compound, thereby replenishing sodium ion loss caused by SEI film formation or other side reactions during the initial charge.

The invention provides a spherical nickel oxide material and a preparation method thereof. The preparation method comprises the following steps: S1, carrying out first mixing on raw materials including a nickel salt solution and an alkali solution to obtain a first mixed solution; s2, performing second mixing on raw materials including the first mixed solution, a surfactant and a dispersing agent to obtain a second mixed solution; s3, sequentially carrying out third mixing and aging reaction on raw materials comprising the second mixed solution and an oxalate solution to obtain a third mixed solution; and S4, sequentially centrifuging, washing, drying and roasting the third mixed solution to obtain the spherical nickel oxide material, wherein the pH value of the first mixed solution is 5.0-6.8; the roasting temperature is 300 to 550 DEG C; according to the preparation method, the needle-shaped spherical nickel oxide material with uniform particle size can be obtained, so that the surface activity and the specific surface energy of the nickel oxide material are enhanced, and the nickel oxide material can be better applied to the fields of gas sensitive materials and the like.

The invention discloses an additive for a secondary battery, a non-aqueous electrolyte for the secondary battery and the secondary battery, the electrolyte comprises a main salt, a non-aqueous solvent and an additive, the main salt is selected from a main lithium salt or a main sodium salt, the additive at least comprises a diester compound shown as a structural formula (I), and can also comprise boron-containing oxalate and a basic additive, the specific structure is shown in the specification. By adding the diester compound into the electrolyte, the initial impedance of the battery can be effectively reduced, the low-temperature discharge performance is improved, and meanwhile, the high-temperature storage and high-temperature circulation of the battery are improved.

The application provides a kind of alkali leaching recovery method of waste oxide battery positive material, comprising: with the mixed aqueous solution of glycine, alkali and oxalate as the alkali leaching bottom solution, adding waste oxide battery positive material, soluble ferrous salt into the alkali leaching bottom solution, and carrying out leaching reaction. The method can realize the reduction of high-valence metal in oxide waste lithium ion battery positive material by using the reducing property of ferrous ion, can effectively improve the leaching efficiency of valuable metal, shorten the time of alkali leaching, and obtain higher metal leaching rate. And the leaching method can effectively avoid the entry of iron ion into liquid phase in the leaching process, causing a series of problems such as difficult separation of valuable metal in subsequent process, the reagent used is simple, the method condition is simple and easy to control, the energy consumption is low, the efficiency is high, and it has considerable industrial application prospect.

The present application relates to a kind of recycling method of avibactam intermediate production waste liquid, belong to pharmaceutical chemical technology field;The present application will be in the 5-benzyloxyamine piperidin-2S-formic acid ethyl ester oxalate in avibactam intermediate production waste liquid by desalination into free state, under the condition of ethyl acetate as solvent, using the dilute solution of m-chloroperbenzoic acid drop, homogeneous reaction in organic solvent, effectively improve the utilization of raw material, with the advantage of less by-product, and have higher recovery rate than prior art, in addition, the present application also prepares a kind of activated carbon loaded sodium triacetoxyborohydride, can play the role of catalytic sodium triacetoxyborohydride reduction amination reaction, improve the utilization of sodium triacetoxyborohydride, and prevent sodium triacetoxyborohydride from contacting with water.

A method of recovering iridium in a platinum group metal refining process by dissolving iridium from a solid iridium containing material into an aqueous solvent to produce an iridium containing solution, wherein the solution is acidic and / or is acidified by addition of an acid (e.g. HCl) after dissolution of the iridium; adding an aliphatic polyamine (e.g. diethylenetriamine or ethylenediamine) to the solution to precipitate the iridium as an iridium polyamine salt; and separating the precipitated iridium polyamine salt from the solution. A majority of the iridium is dissolved in its +3 oxidation state and remains in this state throughout the precipitation and separation steps. The sold iridium (e.g. an iridate or an iridium oxide) can be reduced from its +4 oxidation state when it dissolved using an oxalate or oxalic acid reducing agent. The solution comprises substantially no rhodium or ruthenium.

The invention relates to the technical field of medicines, and discloses a salt, a crystal form and a composition of an AXL kinase inhibitor as well as a preparation method and application of the salt, the crystal form and the composition of the AXL kinase inhibitor, and the salt is hydrochloride, sulfate, phosphate, mesylate, benzene sulfonate, p-toluenesulfonate, camphorsulfonate, maleate and oxalate. The crystalline form of the AXL kinase inhibitor salt is substantially pure. The basically pure AXL kinase inhibitor crystal form disclosed by the invention has good performance and high bioavailability; therefore, the compound can be used for preparing medicines for treating and / or preventing proliferative diseases, autoimmune diseases, allergic diseases, inflammatory diseases, transplant rejection, cancers, virus infectious diseases, heart failure, cardiovascular diseases or other diseases of mammals.

The invention provides a preparation method of a zinc-based metal organic framework material, which is carried out in a water phase at normal temperature and normal pressure, does not need to use organic solvents such as methanol, DMF (Dimethyl Formamide) and the like, is simple and convenient to operate, environment-friendly and low in cost, and is a green preparation method. The preparation method provided by the invention comprises the following steps: S1, adding alkali metal oxalate into a zinc salt aqueous solution, and stirring to obtain a white turbid liquid; the ratio of the amount of substance of oxalate in the alkali metal oxalate to the amount of substance of zinc ions in the zinc salt is (1-4): 1; s2, mixing a benzotriazole aqueous solution with the pH value of more than 8.5 with the white turbid liquid obtained in the step S1, and stirring to react; the molar ratio of the benzotriazole to zinc ions in the zinc salt is (3-10): 1; the pH value of the benzotriazole aqueous solution is adjusted to be greater than 8.5 by adding organic amine; and S3, separating the reaction feed liquid obtained in the step S2, and washing and drying a solid product obtained by separation to obtain the zinc-based metal organic framework material.

The present application relates to a kind of preparation methods of pressurized water reactor MOX fuel powder, comprising the following steps: by mixed actinide salt and urea solid preparation mixed actinide eutectic, mixed actinide eutectic is directly obtained by deamination, denitrogenation / decarbonation, reduction, MOX fuel powder;The mixed actinide salt is hexavalent actinide nitrate and tetravalent actinide oxalate;When the mixed actinide salt is uranyl nitrate hexahydrate solid and thorium oxalate hexahydrate solid, the MOX fuel powder is (U x Th 1‑x )O2;When the mixed actinide salt is uranyl nitrate hexahydrate solid and plutonium oxalate hexahydrate solid, the MOX fuel powder is (U x Pu 1‑x )O2.The method provided by the present application has simple raw materials, can greatly simplify the preparation process of MOX fuel powder composed of UO2 and PuO2 (or ThO2), reduce the use of process reagent, and does not produce any process waste liquid, thereby providing a simple, high production efficiency, waste liquid-free, more economical and green MOX fuel powder preparation method.

Provided herein are methods for preparing Inonotus obliquus (chaga mushroom) extracts that are substantially free of oxalic acid or oxalate, and to food products containing such extracts.

To provide a crystal of 2 - (4-acetylbenzyl) - 3 - ((4-fluorophenyl) amino) - 577 - trimethyl-7, 8-dihydro-pyrazolo-imidazo [1, 2-a] 2H [4, 3-e] pyrimidin-4 (5H) - one.SOLUTION: Provided is a crystal of an acid addition salt form selected from, for example, succinate form, citrate form, adipate form, tartrate form (e.g., L-tartrate form), malate form, gluconate form (e.g., D-gluconate form), maleate form, fumarate form, aspartate form (e.g., L-aspartate form), hippurate form, sebacate form, glycolate form, galactarate form, benzoate form, pamoate form, oxalate form and malonate form.SELECTED DRAWING: None

This application provides a method for preparing high-whiteness aluminum hydroxide based on oxalate filter cake, belonging to the field of aluminum hydroxide preparation. The method includes: adding sodium oxalate circulating seed to the Bayer process seeding mother liquor to obtain an oxalate filter cake containing aluminum hydroxide; adding sodium carbonate to the oxalate filter cake to adjust the alkali ratio to 0.85–1.15, and adding lime to the oxalate filter cake to obtain a mixture; sintering the mixture to obtain sintered clinker; dissolving the sintered clinker to obtain a sodium aluminate solution; and seeding the sodium aluminate solution to obtain high-whiteness aluminum hydroxide. This application, through precise coupling of process parameters and a full-process design of the impurity control chain, simultaneously achieves deep removal of key impurities such as Fe and Si during the oxalate removal process, transforming the oxalate filter cake from waste into a high-quality raw material for high-whiteness aluminum hydroxide, thus combining the removal of organic matter from oxalate and the preparation of high-whiteness aluminum hydroxide in the Bayer process alumina production.

The invention discloses a method for detecting oxalate in calcium gluconate and sodium chloride injection, and relates to the technical field of drug analysis and detection. The detection method comprises the following steps: S1, preparing a test solution and a reference solution; s2, adding hydrochloric acid and high-purity zinc into the test solution, standing for 4-6 minutes, adding a phenylhydrazine hydrochloride solution into the test solution, heating until boiling, immediately cooling, and adding hydrochloric acid and a potassium ferricyanide solution to obtain a first mixed solution; adding hydrochloric acid and high-purity zinc into the reference substance solution, standing for 4-6 minutes, adding a phenylhydrazine hydrochloride solution into the reference substance solution, heating until boiling, immediately cooling, and adding a hydrochloric acid solution serving as a potassium ferricyanide solution to obtain a second mixed solution; and judging whether the content of oxalate in the test solution exceeds the standard or not by comparing the color depth of the first mixed solution and the color depth of the second mixed solution. Oxalates in the calcium gluconate and sodium chloride injection can be visually and rapidly detected through colorimetry, specificity and durability are good, and operation is easy and convenient.

Provided in the embodiments of the present application is a preparation method for an MOX fuel powder. An MOX fuel powder comprises a plurality of actinide nuclide oxides. The method comprises the following steps: S1, mixing different actinide nuclide salts with urea to form a mixed actinide eutectic system, the actinide nuclide salts being one of hexavalent actinide nitrates, tetravalent actinide nitrates, hexavalent actinide oxalates and tetravalent actinide oxalates; S2, heating the mixed actinide eutectic system obtained in step S1 to a first preset temperature for performing deamination treatment on the mixed actinide eutectic system, so as to remove the urea therein; and S3, heating the product obtained after the deamination treatment in step S2 to a second preset temperature for performing denitrification and / or decarburization treatment on the product obtained in step S2, so as to obtain a plurality of actinide nuclide oxides. Provided in the embodiments of the present application is the preparation method for an MOX fuel powder, which is simple, does not produce a waste liquid, is more economical and environmentally friendly, and can obtain a completely uniform MOX fuel powder.

Provided are a salt and / or a crystal form of a compound degrading BTK and preparation and application thereof. The pharmaceutically acceptable salt and crystal form of the compound as shown in formula (I), wherein the pharmaceutically acceptable salt is selected from a maleate salt, a fumarate salt, a hydrogen halide salt (preferably a hydrobromide salt and a hydrochloride salt), a sulfate salt, a phosphate salt, an L-tartrate salt, a citrate salt, an L-malate salt, a hippurate salt, a D-glucuronate salt, a glycolate salt, a mucate salt, a succinate salt, a lactate salt, an orotate salt, a pamoate salt, a glycine salt, an alanine salt, an arginine salt, a cinnamate salt, a benzoate salt, a benzene sulfonate salt, a p-toluene sulfonate salt, an acetate salt, a propionate salt, a valerate salt, a triphenylacetic acid salt, an L-proline salt, a ferulic acid salt, a 2-hydroxyethanesulfonate salt, a mandelate salt, a nitrate salt, a methanesulfonate salt, a malonate salt, a gentisate salt, a salicylate salt, an oxalate salt or a glutarate salt:

A lithium primary battery 10 disclosed herein comprises a positive electrode 1, a negative electrode 2, and a non-aqueous electrolyte. The positive electrode 1 contains manganese dioxide. The negative electrode 2 contains at least one among metallic lithium and a lithium alloy. The non-aqueous electrolyte contains: at least one compound selected from the group consisting of oxalate salts, sulfonylimide salts, and isocyanate compounds; and a cyclic imide compound.

The present invention relates to a method for preparing large-particle cobalt tetroxide for batteries, belonging to the technical field of battery preparation. The method first dissolves a cobalt salt in deionized water to obtain a high-concentration cobalt ion solution, then mixes sodium oxalate and ammonium niobium oxalate to form a specific precursor structure. The cobalt ions, oxalate, and ammonium niobium oxalate undergo a coprecipitation reaction in the aqueous solution to generate a complex precipitate of oxalate and niobate containing cobalt. Hydrogen peroxide is then used to promote the oxidation of the cobalt ions, further promoting the formation and crystallization of the cobalt oxalate precipitate. During the preparation process, freeze-drying is used to effectively remove moisture while maintaining the morphology and structure of the precipitate. Organic matter and volatile impurities are removed through calcination and re-calcination, promoting the formation and stabilization of the cobalt tetroxide crystal structure. This stable crystal structure helps to improve the cycle life and safety of the battery.

Belonging to the technical field of phenothiazine derivative synthesis, the invention relates to a synthesis method of high purity dioxopromethazine hydrochloride, which comprises: adding toluene and dioxophenothiazine into a reaction kettle, stirring, adding a sodium hydroxide solid and a 2-chloro-N, N-dimethyl-1-propylamine toluene solution, carrying out heating reflux reaction, liquid separation, washing, concentration, adding a solvent, heating, adding an acid to adjust the pH value, and cooling to room temperature to obtain the high purity dioxopromethazine hydrochloride. Stirring, cooling and crystallizing, filtering and drying to obtain dioxopromethazine oxalate; the preparation method comprises the following steps: adding toluene and purified water into a reaction kettle, adding dioxopromethazine oxalate while stirring, adjusting the pH value, separating liquid, washing with water, concentrating, adding acetone, decolorizing, filtering, transferring into a reaction bottle, heating, introducing hydrochloric acid gas to adjust the pH value, stirring, cooling, continuing stirring for crystallization, filtering, and drying to obtain dioxopromethazine hydrochloride. The whole process is free of dangerous reaction, the post-treatment method is conventional liquid separation, salting and crystallization, the operation is simple, and the dangerous process that oxidizing agents such as oxygen and hydrogen peroxide are used for oxidation reaction in the conventional synthesis process is avoided.

The invention relates to the technical field of surface treatment, and discloses a gold plating solution, a preparation method thereof and an electroplating process. According to the total volume of the gold plating solution, the gold plating solution comprises the following components by concentration: 1-20 g / L of gold salt; 100 to 230 g / L of citrate; 20 to 50g / L of oxalate; 0.5-5 g / L of a transition metal additive; 4-10 g / L of an antioxidant; 1-5 g / L of a surfactant; wherein the pH value of the gold plating solution is 4-4.8, and the specific gravity of the gold plating solution is 10-15; the citrate comprises potassium citrate and citric acid; the transition metal additive is selected from at least one of cobalt salt, nickel salt and ferric salt. The preparation method is simple, and the prepared gold plating solution is used for the steps of base material pretreatment, electroplating treatment and aftertreatment in the electroplating process, so that the prepared gold plating product has excellent binding force, wear resistance, corrosion resistance and the like.

The application belongs to the technical field of adsorbing materials, and particularly relates to a high-selectivity strontium adsorbing material, a preparation method and application. The preparation method of the high-selectivity strontium adsorbing material comprises the following steps: loading rare earth ions on collagen fibers to obtain an intermediate material; and reacting an oxalate salt and a dimethylamine cation mixed solution with the intermediate material to generate a MOF crystal material with cavities in situ. The application takes dimethylamine cations as exchange ions, and the crystal structure formed by the coordination of rare earth ions and oxalate ions has a cavity size matching the hydrated ion radius of strontium, and has high selectivity to strontium ions, so that the strontium ions can be removed with high selectivity in the presence of various ions.

The application belongs to the technical field of compound preparation, and particularly relates to a preparation method of an alkali metal salt of an oxalate chelate structure, at least comprising the following steps: mixing tris(trimethylsilyl) phosphate, an oxalate and a phosphorus-containing or boron-containing fluorine compound in a first organic solvent, stirring and heating to obtain lithium phosphate, trimethyl fluorosilane gas, and difluorobisoxalate phosphate or difluorooxalate borate, filtering the reaction solution to obtain lithium phosphate solid and a difluorobisoxalate phosphate solution or a difluorooxalate borate solution; adding a second organic solvent for recrystallization after concentration; and obtaining difluorobisoxalate phosphate or difluorooxalate borate solid after filtration, and drying the solid under reduced pressure to obtain a finished product. The process is simple, and the cost is low. By-products lithium phosphate, potassium fluoride and hexamethyldisiloxane can be directly sold as products after purification. Therefore, the application has an atomic utilization rate close to 100%, no invalid waste, less three-waste emissions, and is friendly to the environment.

Battery comprising: a positive electrode plate, a negative electrode plate, a separator and an electrolyte, wherein: the negative electrode plate has a porosity φ in the unit %; the separator has a thickness t in the unit µm and a pore size R in the unit µm; a ratio of the total mass of the electrolyte to the discharge capacity of the battery N in the unit g / Ah; and the electrolyte comprises an electrolyte additive, wherein the electrolyte additive comprises a sulfate ester compound and a first lithium salt additive, wherein the first lithium salt additive comprises an oxalate-containing lithium salt and the sulfate ester compound has a structure represented by formula I: Formula I, wherein: R1 and R8 are each independently selected from hydrogen or C1 to C5 hydrocarbyl; R2, R3, R4, R5, R6, and R7 each independently from C1- to C3-alkylenes, C1- to C3- alkoxy, an oxygen atom, or are selected; and n is an integer in the range of 0 to 4, and a mass fraction of the sulfate ester compound in the electrolyte C in the unit %; and the battery corresponds to formula A: 0.01 ≤ φ × N × C 10 4 × t × R ≤ 0.5

The application relates to the field of electrode materials, in particular to a composite metal oxalate catalytic material, an electrode and a preparation method thereof and an oxygen evolution method of electrolytic alkaline brine. The preparation method of the composite metal oxalate catalytic material comprises the following steps: taking soluble first metal salt, soluble second metal salt and soluble oxalate as raw materials, mixing the soluble first metal salt, the soluble second metal salt and the oxalate in a liquid medium, and preparing the composite metal oxalate catalytic material by using a hydrothermal method or a coprecipitation method; the soluble first metal salt comprises at least one of nickel salt, cobalt salt, manganese salt, chromium salt, copper salt and vanadium salt, and the soluble second metal salt comprises iron salt. The electrode obtained by arranging the composite metal oxalate catalytic material on a conductive substrate has good chlorine resistance and excellent stability, and the Faraday efficiency reaches 99.22%; through cyclic voltammetry test, the electrode can save a large amount of electric energy in application.

The invention belongs to the technical field of hydrometallurgy and water treatment, and relates to a method for removing potassium from a lithium-potassium mixed solution with high selectivity and application of the method. The method comprises the following steps: adding oxalate into a lithium-potassium mixed solution, reacting, and carrying out solid-liquid separation; dropwise adding soluble magnesium salt into the filtrate, and reacting; synchronously dropwise adding a sodium dihydrogen phosphate solution and an alkali solution into the solution, controlling the proportion of the sodium dihydrogen phosphate solution and the alkali solution through the dropwise adding speed, and maintaining the pH value of a reaction system to be 8.8-9.2 in the whole process by utilizing an automatic pH control system; and after the reaction is completed, carrying out solid-liquid separation to obtain a low-potassium solution and a potassium magnesium phosphate precipitate. According to the method, low-temperature, synchronous dropwise adding and multi-protection synergistic processes are combined, so that the potassium ions can be efficiently removed, the loss rate of the lithium ions can be reduced to an extremely low level, and the method is suitable for the scenes with extremely high requirements on the retention rate of the lithium ions, such as salt lake lithium extraction and waste lithium battery recovery liquid.