67results about "Magnesium chlorides" patented technology

The invention belongs to the technical field of anhydrous magnesium chloride production, and particularly relates to a preparation process of anhydrous magnesium chloride, which comprises the following steps: firstly, dissolving magnesium chloride hexahydrate in absolute ethyl alcohol to form a magnesium chloride ethanol aqueous solution, and then dehydrating the magnesium chloride ethanol aqueous solution by using a molecular sieve to obtain the magnesium chloride ethanol solution; carrying out secondary cooling, stirring crystallization, secondary solid-liquid separation and vacuum drying on the magnesium chloride ethanol solution to obtain high-purity anhydrous magnesium chloride; and recycling ethanol liquid obtained by solid-liquid separation and ethanol gas obtained by vacuum drying. The technical scheme provided by the invention is simple in process flow, low in energy consumption, low in equipment requirement, high in product yield and high in purity, and can be directly applied to the fields of electrolytic preparation of magnesium, catalyst carriers and the like.

It is provided a process for extracting nickel sulfate from mining ores, such as serpentine, comprising the steps of conducting a magnetic separation of the mining ores producing a magnetic fraction and a non magnetic fraction; leaching the non magnetic fraction with HCI producing a slurry comprising metals chloride; filtrating the slurry producing a metals chloride liquor; purifying the metals chloride liquor producing a magnesium chloride solution; separating an iron-nickel cake from the magnesium chloride solution; leaching the cake together with the magnetic fraction producing a metallic sulfate solution; extracting nickel and cobalt from the metallic sulfate solution by a ion exchange resin extraction and stripping producing an inorganic stripped phase; submitting the inorganic stripped phase to a liquid-liquid extraction producing a nickel concentrated phase; and evaporating and drying the nickel concentrated phase to recuperate nickel sulfate.

The invention discloses a low-temperature dehydration method of hydrous magnesium chloride and anhydrous magnesium chloride, comprising the following steps: contacting hydrous magnesium chloride with ammonium chloride to obtain a mixed dehydrated raw material; and heating the mixed dehydrated raw material, and keeping the temperature for a certain time after the mixed dehydrated raw material reaches a set temperature until water in the water-containing magnesium chloride is removed. The invention also provides the anhydrous magnesium chloride prepared by the method. According to the method, synthesis of carnallite is not needed, hydrogen chloride protective gas is not needed, dehydration can be achieved through independent ammonium chloride, equipment is hardly corroded, the operation environment is good, and anhydrous magnesium chloride is prepared under the mild condition.

This invention provides a production process for manufacturing metallic magnesium and industrial silicon by decomposing serpentine using the hydrochloric acid method. [Solution] The present invention provides a method for processing serpentine ore as a raw material using a two-stage countercurrent hydrochloric acid leaching process. The wet process steps include storage and filtration of the slurry after ore dressing, two-stage hydrochloric acid leaching under atmospheric pressure, washing and filtration of the silicon slag after leaching, removal of iron and nickel precipitation from the leaching solution, separation, washing and filtration of the obtained iron hydroxide and nickel hydroxide, crystallization and evaporation of the magnesium chloride solution, and production of hydrochloric acid using the gas generated after the thermal decomposition of magnesium chloride. The present invention has developed a serpentine decomposition technology using hydrochloric acid, a metallic magnesium production process using a drying-electrolytic method, and a process for producing industrial silicon by smelting silicon slag in an electric furnace.

The invention belongs to the technical field of inorganic salt preparation, and discloses a method for preparing anhydrous magnesium chloride by dehydrating magnesium chloride hexahydrate, which comprises the following steps: by taking magnesium chloride hexahydrate as a raw material, carrying out preliminary dehydration to obtain low-water magnesium chloride, mixing the low-water magnesium chloride with fluid ammonia to carry out solid-liquid reaction, then carrying out solid-liquid separation and reduced pressure treatment to obtain a solid phase, and further performing high-temperature deamination to obtain anhydrous magnesium chloride. According to the method disclosed by the invention, solid-liquid reaction is directly carried out on the fluid ammonia and the low-water magnesium chloride, so that the use of a large amount of organic solvents and complicated operation steps in a traditional ammonia-gas-based alcohol ammonia method are avoided. Compared with a gas-solid reaction, the solid-liquid reaction has the advantages of being high in reaction speed, high in yield and the like, separation of ammonia and water can be achieved only through decompression treatment, and therefore recycling of ammonia is easy to achieve. Meanwhile, the method avoids corrosion of acid gas to equipment in a gas protection heating method taking hydrogen chloride as protective gas, and large-scale and rapid dehydration of magnesium chloride hexahydrate can be realized.

The invention relates to the technical field of chemical engineering, and provides a calcium chloride and magnesium chloride production device and a production method for preparing calcium chloride and magnesium chloride from dolomite, and the production device comprises a pretreatment assembly, a first-stage reaction kettle and a second-stage reaction kettle which are connected in sequence. The second-stage reaction kettle comprises a tank body, a first outlet formed in the upper part of the tank body and a second outlet formed in the bottom of the tank body. The first outlet is sequentially connected with a water washing tower, a drying device and an evaporation condenser. The second outlet is sequentially connected with a reduced-pressure evaporator, a low-temperature crystallizer, a horizontal centrifuge, a purification tank and a normal-pressure evaporator. The pretreatment assembly, the first-stage reaction kettle and the second-stage reaction kettle are sequentially arranged, so that gradient control over the reaction process is achieved, it is ensured that the acidolysis reaction is more thorough, the chemical purity of calcium chloride and magnesium chloride is improved, precise separation of gaseous impurities and liquid impurities is ensured, and the purification rate of a final product is further increased.

The invention discloses a method for purifying carnallite, purified carnallite and application of the purified carnallite. The method comprises the following steps: uniformly mixing sodium-containing carnallite, old brine and water to form a mixed system, wherein the mass ratio of the sodium-containing carnallite to the old brine to the water in the mixed system is 1: (3.56-6.15): (0-0.28); heating the mixed system to completely dissolve potassium in the sodium-containing carnallite in a liquid phase to obtain a mixed solution; carrying out solid-liquid separation on the mixed solution to obtain a carnallite saturated solution; and adding water into the carnallite saturated solution to separate out crystals, thereby obtaining the purified carnallite. According to the method provided by the invention, the carnallite is dissolved by using the old brine under a high-temperature condition to obtain a carnallite saturated liquid phase, and the carnallite can be separated out by cooling and crystallizing, so that the content of sodium chloride in the carnallite can be effectively reduced.

The present disclosure provides a method for extracting potassium bicarbonate from a mineral mixture. The method includes combining potassium chloride, sodium bicarbonate, and magnesium carbonate trihydrate in an aqueous solution. The aqueous solution is cooled to form Engel's salt comprising potassium bicarbonate magnesium carbonate tetrahydrate. Engel's salt is separated from the aqueous solution and leached with water to produce an aqueous potassium bicarbonate solution and magnesium carbonate trihydrate. The method may further include recycling at least a portion of the magnesium carbonate trihydrate produced from leaching Engel's salt back into the aqueous solution. The aqueous potassium bicarbonate solution can be processed to produce various potassium bicarbonate products.

The present disclosure relates to a process of extracting magnesium or magnesium compounds from a ferronickel slag feed comprising magnesium and silica compounds, the process comprising: a comminution step to reduce a particle size distribution of the ferronickel slag feed; and an acid leaching step after the comminution step, comprising: leaching the ferronickel slag feed from the comminution step in a vessel with hydrochloric acid at a concentration of 5-15 wt.% HCl to form a leached slurry, controlling the hydrochloric acid concentration during leaching by adding further hydrochloric acid to the vessel to maintain the hydrochloric acid concentration at 5-15 wt.% HCl, and obtaining a leached slurry from the vessel, wherein the leached slurry comprises a liquid portion and a solids residue, and wherein the liquid portion comprises magnesium chloride.

The present disclosure relates to a method of carbon dioxide mineralisation, the method comprising: treating a material, such as a mineral, with carbon dioxide and a base, wherein the treatment occurs in solution phase, the material comprising: a first cation that is Ca or Mg; a second cation which is not Ca and or Mg; and one or more anions which are not carbonate; such that a product solution comprising an acid or a salt of the base and one of the one or more anions and a salt of the second cation and one of the one or more anions is formed, and a carbonate salt of the first cation is caused to precipitate.

A method for producing Mg-containing particles by performing a classification process using a centrifugal airflow classifying device, the centrifugal airflow classifying device including: a housing; a rotating body that rotates within the housing; a classification chamber located on an outer edge side of the rotating body; and a flow path formed by an inner surface of the housing and a top surface of the rotating body, connecting an upstream end portion with the classification chamber, wherein the method for producing Mg-containing particles includes: supplying the unclassified Mg-containing particles to the classification chamber so that an average flow velocity of the unclassified Mg-containing particles on a downstream side from the upstream end portion in the flow path is lower than an average flow velocity of the unclassified Mg-containing particles at the upstream end portion flowing inside the flow path; and classifying the unclassified Mg-containing particles in the classification chamber to obtain Mg-containing particles, wherein an attrition durability A (%) of the unclassified Mg-containing particles calculated by the following formula (1) is 85 or less: A = (Z ÷ Y) x 100... (1).

The invention discloses a magnesium alloy workshop slag refining and recycling system and method, and belongs to the technical field of non-ferrous metallurgy and solid waste recycling, the system comprises a pretreatment and activation module, a magnesium metal efficient extraction module, a harmlessness and recycling module and an oxide purification module which are connected in sequence; the method comprises the following steps: carrying out crushing, grinding and low-temperature roasting activation on the magnesium slag in an inert atmosphere; the activated slag powder is subjected to gradient heating smelting, electromagnetic stirring is applied, liquid magnesium is separated and recycled, and meanwhile gaseous magnesium is recycled through vacuum condensation; the smelting residues are subjected to water quenching, solid-liquid separation and evaporative crystallization to recover salts, and condensate water is recycled; and carrying out flotation, acid pickling and calcination on the solid slag to produce high-purity magnesium oxide. Through cooperation of multiple modules, the high recovery rate of magnesium metal, remarkable reduction of energy consumption and full-component recycling of waste residues are achieved, and finally a new efficient, clean and high-value magnesium alloy slag recovery way is formed.

The invention relates to the technical field of chlor-alkali industry, in particular to a chlor-alkali industry salty mud resource utilization device and method.The chlor-alkali industry salty mud resource utilization device comprises a washing pool used for washing salty mud to melt sodium chloride in the salty mud; the first filter press is used for separating a solution containing sodium chloride from the dry salty mud material; the calcium chloride production device comprises a reaction tank for the reaction of limestone and hydrochloric acid, and a neutralization tank for adding alkali for neutralization, the reaction tank is used for receiving the separated dry salty mud material; according to the chlor-alkali industry salty mud resource utilization device and method, calcium ions in calcium carbonate are recycled, and sodium chloride and magnesium hydroxide are recycled, so that recycling is more thorough.

Provided is a method for producing an orally ingestible magnesium compound without heat generation. The method for producing bittern according to the present invention is characterized by bringing flame-retardant magnesium into contact with strongly acidic electrolyzed water generated by electrolysis of an aqueous sodium chloride solution.

The invention provides a seawater concentrated water resource regeneration treatment method based on plate nanofiltration, which comprises the following steps of: after concentrated seawater is subjected to plate nanofiltration, settling and separating the concentrated water to obtain gypsum, and extracting the gypsum to obtain mother liquor; the mother liquor after gypsum extraction is subjected to bromine extraction to obtain a bromine product and mother liquor after bromine extraction, the mother liquor after bromine extraction is adjusted to be neutral and subjected to multiple-effect evaporation to obtain condensate water and evaporation mother liquor, the former is partially fed into an external coil pipe of a reaction settler for heat exchange, and the latter is subjected to heat preservation and sedimentation to obtain high-temperature salt slurry and clarified liquor; separating high-temperature salt slurry to obtain magnesium milk and sodium chloride, processing the magnesium milk into a magnesium sulfate monohydrate product, washing the sodium chloride to obtain bitter salt, and feeding part of the bitter salt into concentrated seawater; cooling and crystallizing the clarified liquor to obtain carnallite and mother liquor after carnallite is separated out, washing the carnallite to obtain a potassium chloride product and decomposition washing mother liquor, mixing one part of the two mother liquor with the mother liquor after bromine extraction, feeding the other part of the two mother liquor, condensate water and bitter salt into a magnesium preparation mother liquor pool, and adding caustic soda to obtain a magnesium hydroxide product. According to the method, valuable components in the concentrated seawater can be subjected to resource maximization extraction.

The present disclosure relates to a method that includes treating a layer of ZnTe with a metal halide, where the layer has a first grain size between 25 nm and 250 nm before the treating and the layer has a second grain size after the treating that is larger than the first grain size. In some embodiments of the present disclosure, the ZnTe may include at least one of Zn1-wCdwTe, ZnTe1-xSex, Zn1-yCdyTe1-zSez, or a combination thereof and each of w, x, y, and z are independently between 0 and 0.9, inclusively.

A system and method for producing minerals from divalent ion-containing brine stream includes rejecting sulfate from a divalent-ion rich reject stream in a first nanofiltration seawater reverse osmosis (NF-SWRO) unit, producing solid calcium sulfate dihydrate and a magnesium-rich brine stream in a first concentration unit, concentrating the magnesium-rich brine stream to a saturation point of sodium chloride in a second concentration unit, producing solid sodium chloride and a supernatant product stream in a first crystallizing unit, produce a concentrated magnesium-rich bittern stream from the supernatant product stream in a third concentration unit, and at least one of producing hydrated magnesium chloride from the concentrated magnesium-rich bittern stream in a second crystallizing unit and producing anhydrous magnesium chloride by prilling the concentrated magnesium-rich bitterns stream under a hydrogen chloride atmosphere in a dry air process unit.

A method for preparing metallic magnesium and industrial silicon by decomposing serpentine with hydrochloric acid is provided. Serpentine is used as a raw material, and is processed by a two-stage countercurrent leaching process in a hydrochloric acid system. A hydrometallurgical process is adopted, including beneficiation, wet grinding, slurry storage, filtration, two-stage atmospheric pressure hydrochloric acid leaching, washing and filtration of leached silica slag, iron removal and nickel precipitation from a leachate, separation, washing and filtration of a ferric hydroxide precipitate and a nickel hydroxide precipitate, crystallization and evaporation of a magnesium chloride solution, and hydrochloric acid preparation from a flue gas generated after thermal decomposition of magnesium chloride. The present disclosure develops a process of decomposing serpentine with hydrochloric acid and producing metallic magnesium by a drying-electrolysis method, and a process of producing industrial silicon by smelting silica slag in an electric furnace.

This invention relates to a method for treating and utilizing high magnesium-to-sulfur ratio chlorine-containing wastewater, belonging to the field of environmental protection. This invention utilizes inexpensive calcium alkali to treat high magnesium-to-sulfur ratio chlorine-containing wastewater. During the treatment process, dilute hydrochloric acid is used as a circulation starter. Taking advantage of the difficult-to-remove chloride ions in the wastewater, the calcium alkali is used to generate calcium chloride solution, thereby continuously recovering sulfate ions from the high magnesium-to-sulfur ratio wastewater. Magnesium is converted into magnesium hydroxide, transforming into valuable by-products such as calcium chloride and gypsum, thus achieving resource utilization of waste. This method reduces the environmental impact of wastewater discharge, while also reducing treatment costs and achieving resource recycling. It is highly feasible for existing enterprises and has significant economic, social, and environmental benefits.

The present application relates to a kind of preparation methods of high solubility seawater crystal, comprising the following steps: S1, the sodium chloride of predetermined proportion is mixed with calcium chloride, obtain sodium chloride-calcium chloride premix, wherein calcium chloride is screened before mixing Processed;S2, the magnesium chloride of predetermined proportion, magnesium sulfate and potassium chloride are mixed and stirred, then sodium chloride-calcium chloride premix is added, and seawater crystal is prepared after being mixed uniformly.The method can reduce the adhesion of magnesium sulfate and calcium chloride, reduce the generation of insoluble calcium sulfate, solve the existing seawater crystal dissolution problem from the root, effectively improve the solubility of seawater crystal, speed up the dissolution rate, make the ion release more uniform, solve the problem of insufficient dissolution, easy to block, the dissolution effect of finished product is better than prior art.

This invention provides a method to solve the problem of crystallization of magnesium hydroxide, which is extremely difficult to dissolve in water, in the production of hydrogen by plasma. [Solution] When magnesium chloride aqueous solution is prepared using a hydroxycarboxylic acid such as citric acid or gluconic acid in a molar ratio of 1.2 times or more of magnesium hydroxide to magnesium hydride, the magnesium hydroxide reacts with the aqueous solution and dissolves, so the magnesium hydroxide does not crystallize.

The utility model provides an anhydrous magnesium chloride preparation device. The anhydrous magnesium chloride preparation device comprises: a reaction unit comprising a reaction main body and a heating assembly arranged on the reaction main body, the reaction main body having a reaction chamber; the tail gas treatment unit comprises a main body structure and a spraying assembly, the main body structure is provided with a containing cavity, the containing cavity is communicated with the exhaust end of the reaction cavity, the spraying assembly comprises a first conveying part and a liquid conveying main pipe, the first conveying part is installed on the liquid conveying main pipe, and a spraying head is arranged at the liquid outlet end of the liquid conveying main pipe and located in the containing cavity. The anhydrous magnesium chloride preparation device adopting the technical scheme provided by the utility model can solve the problems that the atmospheric environment is polluted and resources are wasted when a preparation device in the prior art is used for preparing anhydrous magnesium chloride.

The invention relates to the technical field of magnesium chloride production, in particular to a production process for preparing magnesium chloride in an anhydrous system. The method comprises the following steps: firstly, carrying out medium-low temperature grading dehydration on the solid magnesium chloride mineral aggregate to control the total amount of free water and crystal water to be not higher than 0.5 wt%; then directly melting at the temperature of 710-725 DEG C, and reducing the mass fraction of insoluble substances in a melt to 0.05 wt% or below through the combined action of standing deslagging and one-time micropore high-temperature filtration; and after the melt is conveyed in a heat preservation mode with the temperature drop not exceeding 8 DEG C, the melt is rapidly cooled and solidified through a narrow gap, secondary cooling is conducted in the inert atmosphere, nitrogen-filled packaging is conducted, and water dissolution and evaporation steps are not introduced in the whole process. The purity of the obtained flaky magnesium chloride MgCl2 is larger than or equal to 99.5 wt%, impurities such as Ca2 and SO42 meet the food safety standard, meanwhile, the comprehensive energy consumption is reduced by 20%-30% compared with a traditional wet method, and the fresh water consumption is almost zero.

A self-sustainable process and system for treating water wherein at least a portion of the water is fed through a reactor for the removal of carbonates-based chemical by precipitation and at least some of the calcium carbonate precipitant is regenerated to a calcium-based chemical and carbon dioxide which is at least partially utilized to remineralize said fluids in a post-treatment process.

The invention relates to a process for extracting high-purity potassium chloride (KCl) from a carnallite ore (KCl.MgCl2.6H2O) associated with halite (NaCl). The process starts with selective dissolution, prioritising KCl and MgCl2, due to the addition of water at room temperature. Two basification steps follow, involving the addition of potassium hydroxide (KOH) to the solution obtained after dissolving the ore. The first addition makes it possible to extract all of the Mg2+ ions in the form of magnesium hydroxide (Mg(OH)2), an upgraded product. The second addition of KOH seeks to convert all the NaCl into potassium chloride (KCl) and sodium hydroxide (NaOH). This second addition of KOH is carried out in excess to promote the formation of the desired products during the following two crystallisation steps. After the chemical transformations of the mineral solution, a concentration step is undertaken to vaporise the water, thereby promoting the crystallisation of the potassium chloride (KCl). A second concentration is followed by cooling in order to form the solid sodium hydroxide (NaOH). The water vapours generated in the two concentration steps are liquefied by cooling to be recycled. The three solid products resulting from the process are dried to remove moisture, thereby complying with market requirements in terms of purity. The proposed process is characterised by zero-waste management and low water consumption, with more than 90% of the water being recycled initially, as well as recycling of the KOH at the end of the process. In addition, it has low energy requirements, since the dissolution of KOH is exothermic. The KCl production of the process is high due to the regeneration of KCl during the chemical transformations, and the process is characterised by its flexibility with respect to different compositions of the starting ore.

A method for preparing metallic magnesium and industrial silicon by decomposing serpentine with hydrochloric acid is provided. Serpentine is used as a raw material, and is processed by a two-stage countercurrent leaching process in a hydrochloric acid system. A hydrometallurgical process is adopted, including beneficiation, wet grinding, slurry storage, filtration, two-stage atmospheric pressure hydrochloric acid leaching, washing and filtration of leached silica slag, iron removal and nickel precipitation from a leachate, separation, washing and filtration of a ferric hydroxide precipitate and a nickel hydroxide precipitate, crystallization and evaporation of a magnesium chloride solution, and hydrochloric acid preparation from a flue gas generated after thermal decomposition of magnesium chloride. The present disclosure develops a process of decomposing serpentine with hydrochloric acid and producing metallic magnesium by a drying-electrolysis method, and a process of producing industrial silicon by smelting silica slag in an electric furnace.

The application provides a positive electrode material, a preparation method thereof, a positive electrode sheet, a secondary battery and an electric device. The positive electrode material comprises an inner core, a first coating layer covering at least part of the outer surface of the inner core, and a second coating layer covering at least part of the outer surface of the inner core with the first coating layer. The material of the first coating layer comprises lithium and an X element. The material of the second coating layer comprises the X element and a Z element. By forming the first coating layer, residual lithium on the surface of the inner core can be eliminated. The first coating layer has a high oxygen vacancy formation energy, which can reduce or even avoid oxygen dissolution in the inner core, reduce or even avoid the side reaction between oxygen and electrolyte due to oxygen dissolution, and improve the cycle life and safety of the secondary battery. By forming a uniform protective film on the surface of the inner core with the first coating layer, the overflow of oxygen from the position without the first coating layer can be reduced or even avoided.

The present application belongs to the technical field of waste liquid treatment, and particularly relates to a graphite purification waste liquid treatment method and a treatment system. The present application introduces a pre-acid pickling system to utilize waste acid twice, reduces the amount of acid used in the acid pickling process of graphite purification, improves the use efficiency of acid liquid, thereby reducing the cost of the graphite purification process and significantly enhancing the overall economy. The present application also introduces a sodium fluorosilicate production line, effectively realizing the resource utilization of residual fluorosilicic acid and fluorosilicate in waste water. Not only can the operation cost of reagents in the subsequent water treatment process be effectively reduced, but also the produced sodium fluorosilicate can be sold to improve economic benefits. An evaporation crystallization system is used to crystallize and recover valuable salts in waste water. The obtained crystalline salt can be further used as a raw material for other products. The treatment system provided by the present application can realize the resource utilization and recycling of waste acid and waste water, and achieve zero emission.

This invention discloses a magnesium perchlorate concentration apparatus and its production method, comprising a reaction tank 1 and a reaction tank 2, both having inlets; a perchloric acid solution storage tank is connected to the reaction tank 1 and the reaction tank 2 via a split-flow slow-drip pipeline; the reaction tank 1 and the reaction tank 2 are interconnected at the top via a switching pipeline controlled by a bidirectional pump to create a vacuum environment and exchange heat between the tanks; both the reaction tank 1 and the reaction tank 2 have outlets for discharging anhydrous magnesium perchlorate and outlet pipelines for discharging the solution at the bottom. The production method includes a split-flow slow-drip and dual-pipeline solution compensation method for producing concentrated magnesium perchlorate; and a method for concentrating magnesium perchlorate based on the split-flow slow-drip and dual-pipeline solution compensation method for producing concentrated magnesium perchlorate, performing vacuum exchange and heat exchange under the alternating action of the two tanks; thus improving the efficiency, stability, and continuity of magnesium perchlorate concentration production.

The invention discloses a thin-layer composite separation membrane with a high magnesium-lithium separation ratio and a preparation method of the thin-layer composite separation membrane. The preparation method comprises the following steps: carrying out solution blending on ionic liquid and polyether sulfone, carrying out vacuum drying, and then carrying out irradiation through Co-gamma rays; performing extraction and vacuum drying on the grafted blend obtained by irradiation to prepare a membrane casting solution, coating a substrate with the membrane casting solution, immersing the substrate in a coagulating bath, and performing phase splitting and membrane forming to obtain a polymer bottom membrane; dissolving a polyamine monomer in deionized water to obtain a water phase solution; dissolving a multi-acyl chloride monomer in an organic solvent to obtain an organic phase solution; loading the aqueous phase solution into a polymer base membrane; the organic phase solution is coated on the polymer base membrane, and the polyamine monomer in the water phase solution and the polyacyl chloride monomer in the organic phase solution are subjected to interfacial polymerization reaction to form an active polyamide separation layer. The thin-layer composite separation membrane disclosed by the invention has high positively charged property, narrow pore size distribution and relatively good magnesium-lithium selectivity, and can be applied to magnesium-lithium separation.