Method for producing inorganic solution, and apparatus for producing inorganic solution

Abstract

To provide a method for producing an inorganic solution which is hardly dissolved to any of a basic solution and an acidic solution.SOLUTION: In order to provide a novel production method of high energy efficiency, a method for producing an inorganic solution (a method M10 for producing a BeCl2 solution) includes a heating process (S13) of subjecting a powder mixture obtained by mixing powder of an inorganic substance and a hydroxide to dielectric heating to obtain a liquid mixture including the inorganic substances.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method and an apparatus for producing an inorganic solution. [Background technology]

[0002] Beryllium is known to be contained in Be-Si-O ores and Be-Si-Al-O ores. Examples of Be-Si-O ores include bertrandite and phenacite, and examples of Be-Si-Al-O ores include beryl and chrysoberyl. Hereinafter, ores containing beryllium such as these will be referred to as beryllium ores. Beryllium ores are an example of beryllium oxides.

[0003] When producing beryllium, a compound containing beryllium, or an alloy containing beryllium, beryllium is extracted from beryllium ore by dissolving the ore in a solvent. However, dissolving beryllium ore in a solvent is not easy. Acidic solutions such as sulfuric acid are known as solvents that easily dissolve beryllium ore, but beryllium ore is difficult to dissolve even in acidic solutions.

[0004] Therefore, Non-Patent Document 1 describes that beryllium ore can be dissolved in a solvent by subjecting the ore to a pretreatment such as a sintering treatment or a melting treatment. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] "Beryllium", [online], Wikipedia, [Retrieved June 25, 2019], Internet〈URL: https: / / en.wikipedia.org / wiki / Beryllium〉 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the pretreatment of dissolving beryllium ore in a solvent requires a large amount of energy. According to the "Production" section of Non-Patent Document 1, the temperature for sintering is, for example, 770°C, and the temperature for melting is, for example, 1650°C.

[0007] One aspect of the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a novel, highly energy-efficient method for producing a solution of an inorganic substance, such as beryllium ore, that is difficult to dissolve in both basic and acidic solutions. [Means for solving the problem]

[0008] In order to solve the above problems, a method for producing an inorganic solution according to a first aspect of the present invention includes a heating step of obtaining a liquid mixture containing an inorganic substance by dielectrically heating a powder mixture obtained by mixing an inorganic substance powder and a hydroxide.

[0009] In order to solve the above problems, the manufacturing apparatus for an inorganic solution according to a sixth aspect of the present invention includes a mixing section that mixes inorganic powder with hydroxide to obtain a powder mixture of inorganic substance and hydroxide, a container that contains the powder mixture, and an electromagnetic wave generating section that generates electromagnetic waves for dielectric heating. [Effects of the Invention]

[0010] According to one aspect of the present invention, it is possible to produce a solution of an inorganic substance that is difficult to dissolve in both basic and acidic solutions, such as beryllium ore. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a flowchart showing a method for producing a beryllium solution according to a first embodiment of the present invention. [Figure 2]1 is a flowchart showing a method for producing beryllium, a method for producing beryllium hydroxide, and a method for producing beryllium oxide according to second to fourth embodiments of the present invention. [Figure 3] 10 is a flowchart showing a method for separating titanium and lithium according to a fifth embodiment of the present invention. [Figure 4] FIG. 10 is a schematic diagram of a dielectric heating device according to a sixth embodiment of the present invention. [Figure 5] FIG. 5 is a perspective view of an isolator provided in the dielectric heating device shown in FIG. [Figure 6] 5 is a graph showing the temperature of a mixture of beryllium ore and sodium hydroxide and the output of an electromagnetic wave generating unit when a heating step is carried out using the dielectric heating device shown in FIG. [Figure 7] 5 is a graph showing the temperature of sodium hydroxide and the output of an electromagnetic wave generating unit when only sodium hydroxide is induction heated using the dielectric heating device shown in FIG. [Figure 8] 5 is a graph showing the temperature of sodium carbonate and the output of an electromagnetic wave generating unit when only sodium carbonate is induction heated using the dielectric heating device shown in FIG. 4. [Figure 9] FIG. 10 is a schematic view of a beryllium solution manufacturing device provided in a beryllium manufacturing system according to a seventh embodiment of the present invention. [Figure 10] (a) is a schematic diagram of a crystallizer, a dehydration device, and an electrolysis device provided in a beryllium production system according to a seventh embodiment of the present invention. (b) is a schematic diagram of a modified crystallization treatment tank provided in the crystallizer shown in (a). (c) is a schematic diagram of a modified dryer provided in the dehydration device shown in (a). [Figure 11] 1(a) shows a flowchart of a method for producing lithium hydroxide according to an eighth embodiment of the present invention, and FIG. 1(b) shows a flowchart of a method for producing lithium carbonate according to a ninth embodiment of the present invention. [Figure 12] 13 is a flowchart showing a method for producing lithium carbonate according to a tenth embodiment of the present invention. [Figure 13]11 is a flowchart showing a method for producing lithium carbonate according to an eleventh embodiment of the present invention. [Figure 14] 12 is a flowchart showing a method for producing lithium hydroxide according to a twelfth embodiment of the present invention. [Figure 15] 13 is a flowchart showing a method for producing lithium carbonate according to a thirteenth embodiment of the present invention. [Figure 16] 14 is a flowchart showing a method for producing lithium hydroxide according to a fourteenth embodiment of the present invention. [Figure 17] 15 is a flowchart showing a method for producing a nickel compound according to a fifteenth embodiment of the present invention. [Figure 18] 16 is a flowchart showing a method for separating iron according to a sixteenth embodiment of the present invention. [Figure 19] 10 is a graph showing the solubilities of yttrium, lanthanum, cerium, neodymium, samarium, terbium, and dysprosium in monazite obtained in Example 9. DETAILED DESCRIPTION OF THE INVENTION

[0012] [First embodiment] (Method of manufacturing beryllium solution) A method M10 for producing a beryllium solution according to a first embodiment of the present invention will be described with reference to FIG. 1. FIG. 1 is a flowchart of the method M10 for producing a beryllium solution. Note that, hereinafter, the method M10 for producing a beryllium solution will also be simply referred to as production method M10. In this embodiment, a method for producing a BeCl2 solution, which is an aqueous solution of beryllium chloride (BeCl2), which is the hydrochloride salt of beryllium, will be described. The BeCl2 solution is an example of an inorganic solution. However, the beryllium solution produced using manufacturing method M10 is not limited to a BeCl2 solution, and may be a BeSO4 solution, which is an aqueous solution of beryllium sulfate (BeSO4), which is the sulfate salt of beryllium; a Be(NO3)2 solution, which is an aqueous solution of beryllium nitrate (Be(NO3)2), which is the nitrate salt of beryllium; a BeF2 aqueous solution, which is an aqueous solution of beryllium fluoride (BeF2), which is the hydrofluoride salt of beryllium; a BeBr2 aqueous solution, which is an aqueous solution of beryllium bromide (BeBr2), which is the hydrobromide salt of beryllium; or a BeI2 aqueous solution, which is an aqueous solution of beryllium iodide (BeI2), which is the hydroiodide salt of beryllium.

[0013] In this embodiment, spent tritium breeders and neutron multipliers are used as starting materials in manufacturing method M10. However, the starting materials used in manufacturing method M10 are not limited to spent tritium breeders and neutron multipliers, and can be appropriately selected from inorganic materials. Hereinafter, "inorganic materials" refers collectively to inorganic compounds and metals. Furthermore, "inorganic compounds" refers to organic materials or compounds other than organic compounds, i.e., compounds that do not contain carbon. Preferably, inorganic compounds contain metals such as rare metals and rare earths, as described below. Furthermore, metals contain precious metals. Precious metals include gold (Au), silver (Ag), and platinum metals (ruthenium (Ru), rhodium (Rh), palladium (Pd), osmium (Os), iridium (Ir), and platinum (Pt)). There is a demand for recycling precious metals from spent catalysts (e.g., automobile exhaust catalysts) and waste batteries (e.g., fuel cells). Tritium breeders and neutron multipliers are examples of inorganic materials. More specifically, the tritium breeder is an example of a composite oxide, and the neutron multiplier is an example of an intermetallic compound. Note that the inorganic substance used as the starting material may be an industrially produced substance, such as the tritium breeder and the neutron multiplier, or may be a naturally occurring substance, such as an ore, which will be described later.

[0014] For example, Manufacturing Method M10 is suitable when an inorganic substance that is difficult to dissolve in both basic and acidic solutions, such as beryllium ore, is used as the starting material. Beryllium ore is an ore containing beryllium, and Be-Si-O ores and Be-Si-Al-O ores are known. Beryllium ore is an example of a silicate mineral. Examples of Be-Si-O ores include bertrandite and phenacite, and examples of Be-Si-Al-O ores include beryl and chrysoberyl. Beryllium ore is an example of a beryllium oxide. When beryllium ore is used as the starting material, by carrying out Manufacturing Method M10, for example, a BeCl2 solution can be obtained.

[0015] Furthermore, in manufacturing method M10, ores containing one or more types of metals may be used as starting materials. Examples of such ores include lithium ore, dolomite, bauxite, magnetite, chromite, iron ore, cobaltite, sulfide ore, pyrochlore, molybdenite, sphalerite, barite, tantalum ore, wolframite, PGM ore, rutile, silica, monazite, apatite, and xenotime. Lithium ore is an example of a silicate mineral containing lithium (Li). Spodumene (LiAlSiO) is known as a lithium ore. Dolomite is an example of a carbonate mineral containing magnesium (Mg). Bauxite contains aluminum (Al) and gallium (Ga). Magnetite contains vanadium (V). Chromite contains chromium (Cr). Iron ore contains iron (Fe). Cobaltite contains cobalt (Co). Sulfide ores contain nickel (Ni) and antimony (Sb). Biochlore contains niobium (Nb). Molybdenite contains molybdenum (Mo). Sphalerite contains indium (In). Barite contains barium (Ba). Tantalum ore contains tantalum (Ta). Wolframite contains tungsten (W). PGM (Pt Group Metals) ores contain platinum (Pt) and palladium (Pd). Rutile is a form of titanium dioxide (TiO2) crystal and is a mineral with a tetragonal crystal structure. Silica is the name of siliceous minerals and rocks when they are treated as resources. The main component of silica is silicon dioxide (SiO2). Monazite contains rare earth elements. Rare earth elements are a general term for scandium (Sc), yttrium (Y), and lanthanoids. Examples of rare earth elements contained in monazite include yttrium (Y), lanthanum (La), cerium (Ce), neodymium (Nd), samarium (Sm), europium (Eu), terbium (Tb), and dysprosium (Dy). Apatite contains calcium (Ca). Xenotime contains yttrium (Y). Monazite, apatite, and xenotime are all examples of phosphate minerals.

[0016] Ores containing one or more types of metals are also called polymetallic nodules, and examples of these include seafloor hydrothermal deposits, cobalt-rich crusts, and manganese nodules. Seafloor hydrothermal deposits contain base metals such as copper, lead, and zinc, as well as precious metals such as gold and silver, and rare metals. Cobalt-rich crusts contain rare metals such as nickel, cobalt, and platinum. Manganese nodules contain base metals such as copper, and rare metals such as nickel and cobalt.

[0017] Furthermore, in manufacturing method M10, mud containing one or more types of metals may be used as the starting material. As mud containing one or more types of metals, rare earth mud containing rare earth elements is known.

[0018] In manufacturing method M10, glass may be used as a starting material. Like silica, glass is an example of an oxide primarily composed of silicon dioxide (SiO2). Such glass may contain rare earth elements as additives. Other examples of oxides include aluminum oxide (Al2O3) and magnesium oxide (MgO). Oxides also include composite oxides. Composite oxides are oxides other than those derived from natural minerals and contain multiple elements in addition to oxygen. Examples of composite oxides include yttria-stabilized zirconia (YSZ) and cordierite (2MgO·2Al2O3·5SiO2). In manufacturing method M10, ceramics may be used as a starting material. Examples of ceramics include alumina (Al2O3) and titania (TiO2). Note that composite oxides such as yttria-stabilized zirconia and cordierite are also examples of ceramics.

[0019] When these ores or muds are used as starting materials, by carrying out production method M10, it is possible to obtain, for example, hydrochloride solutions of the above-mentioned rare metals and rare earth elements.

[0020] In Manufacturing Method M10, metals may be used as starting materials. Examples of metals include the rare metals and rare earth elements described above. The starting material may also be an alloy containing multiple rare metals and rare earth elements. Examples of metals other than rare earth elements include transition metals. Examples of transition metals include titanium (Ti), chromium (Cr), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), and zinc (Zn). The starting material may also be an alloy containing multiple transition metals. Such transition metal starting materials are often generated as scrap during the manufacturing or processing of machinery, electronic components, etc. Such scrap also includes sludge or wastewater. Sludge is also generated as slag during metal refining. Sludge contains a wide variety of metals, including nickel. When these metals are used as starting materials, carrying out Manufacturing Method M10 can produce, for example, hydrochloride solutions of the rare metals, rare earth elements, and transition metal elements described above. Therefore, these metals can be recycled. Furthermore, when nickel sludge is used as the starting material, elements other than nickel contained in the nickel sludge (e.g., fluorine (F) and sulfur (S)) can be dissolved in the hydrochloride solution by carrying out manufacturing method M10. Therefore, the purity of nickel in the nickel sludge can be increased.

[0021] As described above, the starting material for manufacturing method M10 is diverse. When expressed using the Sturnz classification, the starting material may be any of oxides, intermetallic compounds, silicate minerals, composite oxides, phosphate minerals, oxide minerals, composite oxide minerals, sulfide minerals, tungstate minerals, and sulfate minerals.

[0022] As shown in FIG. 1, the manufacturing method M10 includes a removing step S11, a crushing and mixing step S12, a heating step S13, a dissolving step S14, a first filtration step S15, a sodium hydroxide adding step S16, a second filtration step S17, a hydrochloric acid adding step S18, a first impurity removing step S19, and a second impurity removing step S20.

[0023] (Removal process) The removal step S11 is a step of removing spent tritium breeder materials and neutron multiplier materials, which are filled inside the blanket of a fusion reactor, from the blanket. In the manufacturing method M10, the spent tritium breeder materials and neutron multiplier materials are used as starting materials.

[0024] Examples of tritium breeding materials include lithium oxides. Specifically, lithium titanate (Li2TiO3), lithium oxide (Li2O), lithium aluminate (LiAlO2), and lithium silicate (Li2SiO3 and / or Li4SiO4) are listed. Examples of neutron multiplier materials include beryllium (Be) and beryllium-containing intermetallic compounds (Be 12 Ti and / or Be 12 Examples of the tritium breeder material include tritium breeder material (also called tritium V or beryllium) and neutron multiplier material (also called beryllium V or beryllide). Each of the tritium breeder material and the neutron multiplier material is formed into a minute sphere having a diameter of about 1 mm. The interior of the blanket is then filled with tritium breeder material and neutron multiplier material that are mixed as uniformly as possible. Therefore, the starting material removed from the blanket in the removal step S11 is a mixture of tritium breeder material and neutron multiplier material. In this embodiment, manufacturing method M10 will be described using lithium titanate as an example of the tritium breeder material and beryllium with an oxide layer formed on its surface as an example of the neutron multiplier material. Note that the tritium breeder material and the neutron multiplier material used as starting materials in manufacturing method M10 are not limited to lithium titanate and beryllium, and can be appropriately selected from the examples described above.

[0025] Even when beryllium is used as a neutron multiplier, the majority of it (for example, about 98%) remains as beryllium. Therefore, in order to reduce the operating costs of fusion reactors, there is a strong demand for the establishment of technology to convert beryllium, an expensive element, into a beryllium solution and reuse it. In addition, a layer of beryllium oxide (BeO) forms on the surface of used beryllium. Therefore, simply immersing used beryllium in an acidic solution will hardly dissolve the beryllium contained in the used beryllium.

[0026] As described above, the starting material used in manufacturing method M10 functions as a neutron multiplier and includes at least one of (1) beryllium, (2) an intermetallic compound containing beryllium, (3) beryllium having an oxide layer formed on its surface, and (4) an intermetallic compound having an oxide layer formed on its surface and containing beryllium. The starting material used in manufacturing method M10 may further include lithium oxide, which functions as a tritium breeding material.

[0027] Furthermore, the starting materials used in Manufacturing Method M10 are not limited to spent neutron multipliers and tritium breeders from fusion reactors. The starting materials may also be spent beryllium and its alloys from nuclear energy and accelerator fields other than fusion, or beryllium and its alloys generated as industrial waste in general industry. Manufacturing Method M10 can process (1) spent neutron multipliers and tritium breeders generated in fusion reactors, (2) spent beryllium and its alloys contained in neutron reflectors, neutron moderators, and target materials as neutron sources generated in nuclear energy and accelerator fields other than fusion, and (3) beryllium and its alloys generated as industrial waste in general industry without distinguishing between them to produce new beryllium. Manufacturing Method M10 also allows for the removal of uranium and other elements contained as impurities in these starting materials.

[0028] (Crushing and mixing process) The pulverizing and mixing step S12 is a step carried out after the removal step S11. In the pulverizing and mixing step S12, the starting material is first pulverized to obtain a powder of the starting material. By pulverizing the starting material, the particle size of the starting material is reduced, and even if an oxide layer is formed on the surface of the neutron multiplier material, the oxide layer is mechanically destroyed to expose the beryllium that was covered by the oxide layer. The technique used to pulverize the starting material is not limited and can be appropriately selected from existing techniques, and examples thereof include a ball mill.

[0029] In the pulverizing and mixing step S12, sodium hydroxide (NaOH) is pulverized to obtain sodium hydroxide powder. However, if powdered sodium hydroxide is purchased and used, the step of pulverizing sodium hydroxide in the pulverizing and mixing step S12 may be omitted. In addition, if the sodium hydroxide used in the pulverizing and mixing step S12 is in granular or flaked form, pulverizing the sodium hydroxide in the pulverizing and mixing step S12 may be omitted. The shape of the sodium hydroxide used in the pulverizing and mixing step S12 is not limited. Sodium hydroxide is an example of a hydroxide. The hydroxide used in manufacturing method M10 is not limited to sodium hydroxide, and may be at least one of lithium hydroxide (LiOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), and strontium hydroxide (Sr(OH)2).

[0030] Then, in the pulverizing and mixing step S12, the powder of the starting material is mixed with sodium hydroxide (sodium hydroxide powder in this embodiment) to obtain a powdery mixture of the starting material and sodium hydroxide. Hereinafter, the powdery mixture of the starting material and sodium hydroxide will also be simply referred to as a powdery mixture.

[0031] (Heating process S13) The heating step S13 is a step performed after the grinding and mixing step S12, in which the powder mixture is dielectrically heated to melt the starting materials and sodium hydroxide. By performing the heating step S13, the sodium hydroxide converts the electromagnetic wave energy described below into heat, resulting in a liquid mixture containing the starting materials and sodium hydroxide. Hereinafter, the liquid mixture of the starting materials and sodium hydroxide will also be referred to simply as the liquid mixture. Because the starting materials and sodium hydroxide do not contain water, there is no need to consider water boiling even when the temperature of the powder mixture or liquid mixture exceeds 100°C. Therefore, in the heating step S13, the powder mixture can be dielectrically heated under normal pressure. The liquid mixture obtained by the heating step S13 is in a milky state, and at least a portion of it may change from a milky state to a solid state as the temperature decreases.

[0032] Dielectric heating is a general term for a technique for heating an object by applying electromagnetic waves of a predetermined frequency to the object. Depending on the frequency band of the applied electromagnetic waves, it is also called high-frequency heating or microwave heating. For example, high-frequency heating applies electromagnetic waves in the frequency band of 3 MHz or more but less than 300 MHz (so-called short waves or ultra-short waves) to the object, while microwave heating applies electromagnetic waves in the frequency band of 300 MHz or more but less than 30 GHz (so-called microwaves) to the object. Microwave ovens, which are widely used in homes, are an example of a device capable of microwave heating.

[0033] In this embodiment, electromagnetic waves having a frequency of 2.45 GHz are applied to the powdery mixture in the heating step S13. The configuration of an apparatus for applying electromagnetic waves to the powdery mixture will be described later with reference to FIG. 5 or FIG. 9.

[0034] By using dielectric heating to heat the powder mixture, the starting materials and sodium hydroxide can be converted into a liquid mixture that can be dissolved in an acidic solution with higher energy efficiency than conventional methods. As described below, the liquid mixture is easily soluble in an acid solution (hydrochloric acid in this embodiment), so a hydrochloric acid solution containing beryllium chloride hydrate (BeCl2·xH2O) and lithium chloride (LiCl) can be obtained. Therefore, manufacturing method M10 can provide a novel manufacturing method with high energy efficiency.

[0035] The heating temperature in the heating step S13 can be set as appropriate. However, the heating temperature in the heating step S13 is preferably equal to or lower than the heat-resistant temperature of the container (e.g., the container 14 described in the seventh embodiment) that contains the powdery mixture. For example, if the container is made of polytetrafluoroethylene like the container 14, the heating temperature in the heating step S13 is preferably equal to or lower than 250°C. An example of the heating temperature is 220°C. If the material constituting the container is corrosion-resistant to acidic solutions and has a heat-resistant temperature exceeding 250°C, the heating temperature in the heating step S13 may exceed 250°C. Examples of materials with a heat-resistant temperature exceeding 250°C include alumina (Al2O3) and boron nitride (BN). When a container made of alumina, boron nitride, or the like is used, the heating temperature in the heating step S13 may exceed 250°C. An example of the heating temperature when such a container is used is 300°C. By increasing the heating temperature in the heating step S13, it is highly possible to shorten the time required for the heating step S13. The heating time in the heating step S13 can also be set appropriately. An example of the heating time is 8 minutes.

[0036] In one variation of the heating step S13, a small amount of water may be added to the powdered mixture before the powdered mixture is dielectrically heated. Water can efficiently absorb microwaves applied to the powdered mixture during dielectric heating and convert them into heat. Therefore, by adding a small amount of water to the powdered mixture, the powdered mixture can be quickly heated to a desired temperature (e.g., 250°C). The amount of water to be added to the powdered mixture is not limited, but is preferably 5 wt% or more based on the mass of the powdered mixture.

[0037] (melting process) The dissolving step S14 is a step performed after the heating step S13. The liquid mixture obtained in the heating step S13 is dissolved in an acid solution (hydrochloric acid (HCl) in this embodiment) to obtain a hydrochloric acid solution of the metals contained in the starting materials. In this embodiment, a hydrochloric acid solution containing beryllium chloride hydrate (BeCl2·xH2O) and lithium chloride (LiCl) is obtained. The acid solution used in the dissolving step S14 is not limited to a hydrochloric acid solution, but may be at least one of a sulfuric acid (H2SO4) solution, a nitric acid solution, a hydrofluoric acid solution, a hydrobromic acid solution, and a hydroiodic acid solution, or may be a mixed acid solution obtained by mixing two or more of these acid solutions. An example of such a mixed acid solution is aqua regia, which is obtained by mixing concentrated hydrochloric acid and concentrated nitric acid. In the dissolving step S14, water may also be used as the liquid for dissolving the liquid mixture obtained in the heating step S13.

[0038] In the dissolving step S14, the liquid mixture dissolves even in a hydrochloric acid solution at room temperature and normal pressure, but dissolution of the liquid mixture in the hydrochloric acid solution can be promoted by increasing the temperature of the hydrochloric acid solution. The device for applying electromagnetic waves used in the heating step S13 is suitable as a means for heating the hydrochloric acid solution. In the dissolving step S14, the temperature of the hydrochloric acid solution is preferably set to less than 100°C to prevent the hydrochloric acid solution from boiling. This eliminates the need to pressurize the hydrochloric acid solution, and the dissolving step S14 can be carried out under normal pressure.

[0039] (First filtration step) The first filtration step S15 is a step carried out after the dissolving step S14. The first filtration step S15 is a step of separating a solid phase and a liquid phase contained in the lithium-containing beryllium solution using a filter. The solid phase contains some lithium titanate and titanium oxide. The liquid phase, which is an acidic solution, mainly contains beryllium chloride hydrate and lithium chloride.

[0040] By carrying out the first filtration step S15, it is possible to easily separate the titanium oxide contained in the solid phase from the beryllium chloride hydrate and lithium chloride contained in the liquid phase.

[0041] (Sodium hydroxide addition process) The sodium hydroxide addition step S16 is a step carried out after the first filtration step S15. The sodium hydroxide addition step S16 is a step of adjusting the polarity of the acidic solution separated in the first filtration step S15, which contains beryllium chloride hydrate and lithium chloride in a liquid phase but does not contain titanium oxide in a solid phase, from acidic to basic via neutral.

[0042] In this embodiment, the sodium hydroxide addition step S16 is defined as adding an aqueous solution of sodium hydroxide to the acidic solution separated in the first filtration step S15. As a result, the polarity of the solution separated in the first filtration step S15 changes from acidic to neutral (pH 7) and then to basic, and the beryllium chloride hydrate contained in the solution becomes beryllium hydroxide (Be(OH)2) and precipitates as a solid phase in the basic solution. Note that lithium chloride is dissolved in the basic solution and does not precipitate. That is, lithium chloride remains present in the liquid phase as lithium hydroxide even after the sodium hydroxide addition step S16 is performed.

[0043] (Second filtration step) The second filtration step S17 is a step carried out after the sodium hydroxide addition step S16. The second filtration step S17 is a step of separating, using a filter, the solid phase and the liquid phase contained in the basic solution obtained in the sodium hydroxide addition step S16. The solid phase contains beryllium hydroxide, and the liquid phase contains lithium hydroxide.

[0044] By carrying out the second filtration step S17, it is possible to easily separate the beryllium hydroxide contained in the solid phase from the lithium hydroxide contained in the liquid phase.

[0045] (Hydrochloric acid addition process) The hydrochloric acid addition step S18 is a step carried out after the second filtration step S17. In the hydrochloric acid addition step S18, an HCl solution is added to the beryllium hydroxide obtained in the second filtration step S17, thereby dissolving the beryllium again in the form of beryllium chloride hydrate in the acidic solution. The concentration of HCl in the HCl solution can be adjusted as appropriate, but it is preferably adjusted so that the pH is 1 or less.

[0046] By carrying out the hydrochloric acid adding step S18, a hydrochloric acid solution (also referred to as a beryllium solution or a BeCl2 solution) in which beryllium chloride hydrate is dissolved can be obtained.

[0047] (First impurity removal step) The first impurity removal step S19 is a step carried out after the hydrochloric acid addition step S18. The first impurity removal step S19 is a step of removing the first element from the beryllium solution obtained in the hydrochloric acid addition step S18 using an organic compound that adsorbs the first element.

[0048] The first element to be removed in the first impurity removal step S19 is determined by the organic compound used. Examples of organic compounds that can be used in the first impurity removal step S19 include tri-n-octylphosphine oxide (TOPO), di-(2-ethylhexyl) phosphoric acid (DEHPA), tri-n-butyl phosphate (TBP), and ethylenediaminetetraacetic acid (EDTA). A commercially available organic compound that can be used in the first impurity removal step S19 is UTEVA® resin from Eichrom Technologies.

[0049] TOPO is Al, Au, Co, Cr, Fe, Hf, Re, Ti, UO2 2+ , V, Zr, rare earth elements, and actinide elements. D2EHPA can adsorb U, Co, Ni, Mn, etc. TBP can adsorb U, Th, etc. EDTA and the like can adsorb Mg, Ca, Ba, Cu, Zn, Al, Mn, Fe, etc. UTEVA® Resin can adsorb U, Th, Pu, Am, etc. These elements are examples of the first element.

[0050] These organic compounds dissolve in organic solvents (e.g., kerosene, cyclohexane, benzene, etc.). By mixing the solution in which these organic compounds are dissolved (hereinafter also referred to as organic compound solution) with the HCl solution obtained after the hydrochloric acid addition step S18 has been performed and stirring the mixture, the organic compounds adsorb the first element.

[0051] In the first impurity removal step S19, the HCl solution mixed with the organic compound solution is preferably acidic, and more preferably has a pH of 2 or less. This configuration can increase the efficiency with which the organic compound adsorbs the first element without adsorbing beryllium. Note that the closer the HCl solution is to neutral, the higher the efficiency with which the organic compound adsorbs beryllium and the lower the efficiency with which the organic compound adsorbs the first element.

[0052] In this embodiment, TOPO and kerosene are used as the organic compound and organic solvent used in the first impurity removal step S19. However, the organic compound and organic solvent are not limited to TOPO and kerosene, and can be appropriately selected from the combinations exemplified above.

[0053] The aqueous beryllium solution and the organic compound solution obtained in the hydrochloric acid addition step S18 are separated into two layers by leaving them for a while. Therefore, the beryllium solution in which the content of the first element has been reduced by performing the first impurity removal step S19 can be easily separated from the organic compound solution containing the first element.

[0054] By performing the first impurity removal step S19, the concentration of the first element contained in the beryllium solution can be reduced. As a result, when a beryllium solution is produced by dissolving a starting material in an acidic solution, even if the starting material contains a first element other than beryllium as described above, the concentration of the first element contained in the beryllium solution can be reduced when producing beryllium, beryllium hydroxide, or beryllium oxide from the beryllium solution. Examples of the first element include uranium, thorium, plutonium, and americium.

[0055] As a specific example, when beryllium is produced using beryllium chloride produced using a production method M10 including a first impurity removal step S19, the uranium concentration in the beryllium can be suppressed to less than 0.7 ppm. Even when beryllium with a uranium concentration of less than 0.7 ppm is used as a neutron multiplier in a fusion reactor, the uranium concentration after use falls below the threshold value that determines whether shallow disposal is possible. Therefore, beryllium included in one embodiment of the present invention can be directly disposed of at shallow land even when used as a neutron multiplier in a fusion reactor.

[0056] (Second impurity removal step) The second impurity removal step S20 is a step performed after the first impurity removal step S19, and is a step of removing a second element from the beryllium solution by adjusting the polarity of the beryllium solution obtained in the hydrochloric acid addition step S18 from acidic, via neutral, to basic. Note that, in this embodiment, the first impurity removal step S19 and the second impurity removal step S20 are described as being performed in this order after the hydrochloric acid addition step S18, but the order of the first impurity removal step S19 and the second impurity removal step S20 can be reversed.

[0057] In this embodiment, the second impurity removal step S20 involves adding sodium bicarbonate (NaHCO3) to the beryllium solution after the hydrochloric acid addition step S18 until the solution is saturated. As a result, after the beryllium solution reaches neutrality (pH 7), elements other than beryllium (e.g., Al and Fe) become hydroxides (e.g., Al(OH)3 and Fe(OH)3) and precipitate in the beryllium solution. Note that even when the sodium bicarbonate solution is saturated, Be(OH)2 remains dissolved in the beryllium solution and does not precipitate. Thus, aluminum (Al) and iron (Fe) are examples of the second element.

[0058] The hydroxides of elements other than beryllium that have precipitated in the beryllium solution by carrying out the second impurity removal step S20 can be easily removed from the beryllium solution by filtering the beryllium solution.

[0059] It is preferable to add HCl to the beryllium solution from which the second element has been removed by performing the second impurity removal step S20. By adding HCl to the beryllium solution in this manner, the polarity of the Be(OH)2 solution is adjusted from neutral to acidic, and highly pure beryllium chloride hydrate (BeCl2·xH2O) is produced in the solution.

[0060] In this way, by performing the second impurity removal step S20, the concentration of the second element contained in the beryllium solution can be reduced. As a result, when a beryllium solution is produced by dissolving a starting material in an acidic solution, even if the starting material contains a second element other than beryllium as described above, the concentration of the second element contained when beryllium, beryllium hydroxide, or beryllium oxide is produced using the beryllium solution can be reduced.

[0061] As described above, in manufacturing method M10, the heating step S13 preferably involves dielectrically heating the acidic solution containing beryllium oxide by applying microwaves.

[0062] Furthermore, when manufacturing method M10 includes a preheating step, the preheating step preferably involves dielectrically heating the basic solution containing beryllium oxide by applying microwaves, similar to heating step S13.

[0063] The technology of dielectric heating using microwaves (i.e., microwave dielectric heating) is a technology used in so-called microwave ovens and is widely used. Therefore, manufacturing method M10 can reduce the cost required for implementation compared to conventional manufacturing methods.

[0064] As mentioned above, in manufacturing method M10, the beryllium solution is preferably a beryllium chloride solution.

[0065] According to the manufacturing method M10, a beryllium chloride solution can be easily produced without going through beryllium hydroxide. As will be described later, beryllium, beryllium hydroxide, and beryllium oxide can be easily produced from the beryllium chloride solution. Therefore, a beryllium chloride solution is preferable as the beryllium solution.

[0066] (Modification of Beryllium Solution Manufacturing Method) As described above, in this embodiment, manufacturing method M10 was described using used tritium breeder and neutron multiplier materials as starting materials. In this modified example, manufacturing method M10 using beryl as the starting material will be briefly described. Beryl is a form of Be-Si-Al-O beryllium ore and is an example of an inorganic substance. That is, beryl contains silicon (Si) and aluminum (Al) in addition to beryllium. Note that the starting material may also contain ores other than beryl (for example, spodumene, which will be described later).

[0067] In this modification, beryl quarried from a mine is used as the starting material, so that the extraction step S11 can be omitted.

[0068] In the grinding and mixing step S12, beryl is ground to obtain beryl powder. Similarly, sodium hydroxide is ground to obtain sodium hydroxide powder. Then, the beryl and sodium hydroxide powders are mixed to obtain a powdery mixture of beryl and sodium hydroxide. Note that, in this modification, the form of sodium hydroxide is not limited to powder.

[0069] The heating step S13 and the dissolving step S14 are as described above with reference to Fig. 1. In the heating step S13, dielectric heating is performed so that the temperature of the mixture reaches 220°C, and the heating time is 8 minutes. The liquid mixture obtained in the heating step S13 is a milky milky liquid.

[0070] The melting points of beryl and sodium hydroxide are 1410°C and 318°C, respectively, so the heating temperature in heating step S13 is lower than these melting points. Nevertheless, beryl and sodium hydroxide melt. This is believed to be due to the melting-promoting effect of the application of electromagnetic waves. In Manufacturing Method M10, powdered beryl and sodium hydroxide are mixed, so the applied electromagnetic waves directly affect the interior of the powder mixture, directly heating it. Furthermore, it is believed that discharge occurs within the powder mixture due to the application of electromagnetic waves, and this discharge also promotes melting. As a result, Manufacturing Method M10 can convert beryl into a state that is soluble in hydrochloric acid solution, even at a low temperature of 220°C. The technology described in Non-Patent Document 1 melts beryl at high temperatures, for example, around 2000°C. Compared to this technology, Manufacturing Method M10 reduces energy consumption to approximately 1 / 10,000 (0.01%).

[0071] Even after the heating step S13 and the dissolving step S14, the silicon contained in the beryl remains in the form of a solid oxide in the hydrochloric acid solution. Therefore, by performing the first filtration step S15, the silicon can be removed from the beryllium chloride solution.

[0072] When beryl is used as the starting material, the sodium hydroxide adding step S16, the second filtration step S17, and the hydrochloric acid adding step S18 can be omitted.

[0073] The first impurity removal step S19 and the second impurity removal step S20 are preferably performed even when beryl is used as the starting material. By performing the first impurity removal step S19, the concentration of a first element (e.g., uranium, thorium, plutonium, americium, etc.) contained in the beryllium chloride solution can be reduced. Furthermore, by performing the second impurity removal step S20, the concentration of a second element (e.g., aluminum, iron, etc.) contained in the beryllium chloride solution can be reduced. Although beryl contains aluminum, by performing the second impurity removal step S20, aluminum can be reliably removed from the beryllium chloride solution.

[0074] As described above, by carrying out this modified example, a beryllium chloride solution, which is an example of an inorganic solution, can be easily produced using beryl as a starting material without going through beryllium hydroxide.

[0075] (Method of manufacturing lithium solution) In a variation of the above-described method for producing a beryllium solution, beryl is used as the starting material, and a hydrochloric acid solution containing dissolved beryllium chloride hydrate (BeCl2·xH2O) is obtained. Next, we will briefly explain the case where lithium ore is used as the starting material to obtain a hydrochloric acid solution containing dissolved lithium chloride (LiCl), the hydrochloride salt of lithium. This production method is the same as the variation of the above-described method for producing a beryllium solution, except that the starting material is changed from beryl to lithium ore, and therefore can also be considered a variation of the method for producing a beryllium solution.

[0076] This manufacturing method describes a method for manufacturing a LiCl solution, which is an aqueous solution of lithium chloride (LiCl), which is the hydrochloride of lithium. LiCl solution is an example of an inorganic solution. However, the lithium solution manufactured using this manufacturing method is not limited to LiCl solution, and may be a LiSO4 solution, which is an aqueous solution of lithium sulfate (LiSO4), which is the sulfate of lithium, a LiNO3 solution, which is an aqueous solution of lithium nitrate (LiNO3), which is the nitrate of lithium, lithium fluoride (LiF), which is the hydrofluoride of lithium, lithium bromide (LiBr), which is the hydrobromide of lithium, or lithium iodide (LiI), which is the hydroiodide of lithium.

[0077] Lithium ore is a general term for ores containing lithium and is also an example of lithium oxide. Lithium ore has a crystalline structure. Lithium ores include spodumene (LiAlSiO), lepidolite (K(Al,Li)(Si,Al)O), and spodumene (LiAlSiO). 10 (OH,F)2), Petalite (LiAlSi4O 10 ), and Elbaite (Na(Li,Al)3Al6(BO3)3Si6O 18 (OH)4). In this production method, spodumene, a type of lithium ore, is used as a starting material. In conventional techniques, spodumene is calcined at temperatures above 1000°C to dissolve in the solution.

[0078] In the crushing and mixing step S12, spodumene is crushed to obtain spodumene powder. Similarly, sodium hydroxide is crushed to obtain sodium hydroxide powder. Then, the spodumene and sodium hydroxide powders are mixed to obtain a powdered mixture of spodumene and sodium hydroxide. Note that in this modification, the form of sodium hydroxide is not limited to powder.

[0079] The heating step S13 and the dissolving step S14 are as described above with reference to FIG.

[0080] Even after the heating step S13 and the dissolving step S14, the silicon contained in the spodumene remains in the form of a solid oxide in the hydrochloric acid solution. Therefore, by performing the first filtration step S15, the silicon can be removed from the lithium solution.

[0081] When spodumene is used as the starting material, the sodium hydroxide adding step S16, the second filtration step S17, and the hydrochloric acid adding step S18 can be omitted.

[0082] The first impurity removal step S19 and the second impurity removal step S20 are preferably performed even when spodumene is used as the starting material. By performing the first impurity removal step S19, the concentration of a first element (e.g., uranium, thorium, plutonium, americium, etc.) contained in the lithium solution can be reduced. Furthermore, by performing the second impurity removal step S20, the concentration of a second element (e.g., aluminum, iron, etc.) contained in the lithium solution can be reduced. Although spodumene contains aluminum, by performing the second impurity removal step S20, aluminum can be reliably removed from the lithium solution.

[0083] [Second to Fourth Embodiments] A method M20 for producing beryllium (Be), a method M30 for producing beryllium hydroxide (Be(OH)2), and a method M40 for producing beryllium oxide (BeO) according to second to fourth embodiments of the present invention will be described with reference to (a) to (c) of FIG. 2. (a) to (c) of FIG. 2 are flowcharts showing the main parts of the method M20 for producing beryllium, the method M30 for producing beryllium hydroxide, and the method M40 for producing beryllium oxide, respectively. Note that hereinafter, the method M20 for producing beryllium, the method M30 for producing beryllium hydroxide, and the method M40 for producing beryllium oxide will also be simply referred to as the method M20, the method M30, and the method M40, respectively.

[0084] (Beryllium manufacturing method M20) As shown in Fig. 2, manufacturing method M20 includes the steps of removing S11, pulverizing and mixing S12, heating S13, dissolving S14, first filtration S15, sodium hydroxide adding S16, second filtration S17, first impurity removing S19, and second impurity removing S20, which are included in manufacturing method M10 shown in Fig. 1, as well as a dehydration step S21 and an electrolysis step S22. Hereinafter, the removing S11, heating S13, first filtration S15, sodium hydroxide adding S16, second filtration S17, first impurity removing S19, and second impurity removing S20 will also be simply referred to as each step S11 to S20.

[0085] The steps S11 to S20 of the manufacturing method M10 included in the manufacturing method M20 are the same as the steps S11 to S20 described in the first embodiment. Therefore, the description of the steps S11 to S20 will be omitted here. That is, assuming that a BeCl2 solution in which BeCl2 is dissolved in an HCl solution has been obtained, only the dehydration step S21 and the electrolysis step S22 of the manufacturing method M20 will be described.

[0086] The dehydration step S21 is a step of producing BeCl2, an example of a beryllium salt, by dehydrating beryllium chloride hydrate (BeCl2·xH2O) contained in the BeCl2 solution obtained by steps S11 to S20 of manufacturing method M10.

[0087] In the dehydration step S21, ammonium chloride is added to the beryllium chloride hydrate, and the beryllium chloride hydrate is heated in a vacuum at 90°C for 24 hours, thereby reducing the water content as close to zero as possible. In other words, the beryllium chloride hydrate can be dehydrated.

[0088] Ammonium chloride reacts with the water in the beryllium chloride hydrate to form ammonium hydroxide and hydrochloric acid. The resulting ammonium hydroxide and hydrochloric acid then react again to return to ammonium chloride, releasing water. In this process, anhydrous beryllium chloride can be obtained from the beryllium chloride hydrate.

[0089] The heating temperature in the dehydration step S21 is not limited to 90°C, but can be appropriately selected from the temperature range of 80°C to 110°C. However, if the heating temperature is too high, the dehydration of the beryllium chloride hydrate tends to be insufficient. Therefore, the heating temperature is preferably 80°C to 90°C, and more preferably 90°C.

[0090] The time period for carrying out the dehydration treatment in the dehydration step S21 is not limited to 24 hours, but can be determined as appropriate.

[0091] The electrolysis step S22 is a step of producing metallic beryllium by subjecting the BeCl2 obtained in the dehydration step S21 to molten salt electrolysis.

[0092] As described above, by carrying out manufacturing method M20, metallic beryllium can be produced from the starting material.

[0093] (Beryllium hydroxide manufacturing method M30) 2, production method M30 includes steps S11 to S20 of production method M10 and a neutralization step S31. As in production method M20, only the neutralization step S31 will be described here.

[0094] The neutralization step S31 is a step in which BeCl2·xH2O contained in the BeCl2 solution obtained in each of steps S11 to S20 of the manufacturing method M10 is neutralized with a base to produce Be(OH)2.

[0095] As described above, by carrying out production method M30, Be(OH)2 can be produced from the starting material.

[0096] (Beryllium oxide manufacturing method M40) 2, manufacturing method M40 includes steps S11 to S20 of manufacturing method M10 and a heating step S41. As in manufacturing method M20, only the heating step S41 will be described here.

[0097] Heating step S41 is a third heating step in which BeO is produced by heating the BeCl2 solution obtained by steps S11 to S20 of manufacturing method M10. In this step, BeCl2·xH2O dissolved in the BeCl2 solution is hydrolyzed to produce BeO.

[0098] As described above, by carrying out production method M40, BeO can be produced from starting materials.

[0099] (summary) According to these manufacturing methods M20, M30, and M40, beryllium, beryllium hydroxide, and beryllium oxide can be produced using novel, highly energy-efficient manufacturing methods. Note that the dehydration step S21, electrolysis step S22, neutralization step S31, and heating step S41 can all be carried out using existing technologies.

[0100] Fifth Embodiment (Titanium and lithium separation method M50) A titanium and lithium separation method M50 according to a fifth embodiment of the present invention will be described with reference to Fig. 3. Fig. 3 is a flowchart of the titanium and lithium separation method M50. Note that, hereinafter, the titanium and lithium separation method M50 will also be simply referred to as the separation method M50.

[0101] As shown in Fig. 3, separation method M50 includes the removing step S11, pulverizing and mixing step S12, heating step S13, dissolving step S14, and first filtration step S15 included in production method M10 shown in Fig. 1, as well as the pulverizing step S51, hydrochloric acid soaking step S52, and third filtration step S53. Hereinafter, the removing step S11, pulverizing and mixing step S12, heating step S13, dissolving step S14, and first filtration step S15 will also be simply referred to as each step S11 to S15.

[0102] Steps S11 to S15 of manufacturing method M10, which are included in separation method M50, are the same as steps S11 to S15 described in the first embodiment. Therefore, a description of steps S11 to S15 will be omitted here. That is, assuming that lithium titanate contained in the solid phase and beryllium chloride hydrate and lithium chloride contained in the liquid phase are separated, only the pulverization step S51, the hydrochloric acid immersion step S52, and the third filtration step S53 of separation method M50 will be described. Note that the solid phase after the first filtration step S15 may contain titanium oxide in addition to lithium titanate.

[0103] The pulverization step S51 is a step of reducing the particle size of the lithium titanate by pulverizing the lithium titanate contained in the solid phase after the first filtration step S15. The technique used to pulverize the lithium titanate is not limited and can be appropriately selected from existing techniques, such as a ball mill.

[0104] If lithium titanate can be pulverized more finely, the ratio of the surface area to the total volume of the lithium titanate can be increased, which is expected to shorten the time required to dissolve the lithium contained in the lithium titanate in the solution in the hydrochloric acid immersion step S52 described below. On the other hand, if lithium titanate is pulverized too finely, the time and cost required for the pulverization step S51 will increase. Therefore, it is preferable to determine the particle size of the lithium titanate obtained after performing the pulverization step S51 in consideration of the time required for the hydrochloric acid immersion step S52, the time required for the pulverization step S51, the cost required for the pulverization step S51, etc.

[0105] The particle size of lithium titanate may be any of the average size, mode size, and median size. When the particle size distribution of lithium titanate is measured, the average size is the particle size that is the average value of the obtained particle size distribution, the mode size is the most frequent particle size in the particle size distribution, and the median size is the particle size where the cumulative frequency in the particle size distribution is 50%.

[0106] In this embodiment, the pulverization step S51 is carried out so that the average particle size of the lithium titanate becomes 100 μm.

[0107] The hydrochloric acid immersion step S52 is a step carried out after the pulverization step S51. The hydrochloric acid immersion step S52 is a step of immersing the lithium titanate pulverized in the pulverization step S51 in a hydrochloric acid solution. By carrying out the hydrochloric acid immersion step S52, the lithium contained in the lithium titanate dissolves in the hydrochloric acid solution in the form of lithium chloride, and the titanium contained in the lithium titanate remains in the hydrochloric acid solution in the form of titanium oxide (e.g., TiO2). Therefore, the hydrochloric acid solution after carrying out the hydrochloric acid immersion step S52 contains titanium oxide contained in a solid phase and lithium chloride contained in a liquid phase.

[0108] If it is desired to dissolve the lithium contained in the lithium titanate in the hydrochloric acid solution more quickly, the hydrochloric acid solution containing the lithium titanate may be dielectrically heated by applying a method similar to that in the heating step S13.

[0109] The third filtration step S53 is a step carried out after the hydrochloric acid immersion step S52. The third filtration step S53 is a step of separating titanium oxide contained in the solid phase from lithium chloride contained in the liquid phase using a filter.

[0110] By carrying out the third filtration step S53, it is possible to easily separate the titanium oxide contained in the solid phase from the lithium chloride contained in the liquid phase.

[0111] The acidic solution containing lithium chloride separated in the third filtration step S53 is preferably returned to the sodium hydroxide adding step S16, similar to the acidic solution separated in the first filtration step S15. By separating the lithium contained in the solid phase separated in the first filtration step S15 as lithium chloride and returning it to the sodium hydroxide adding step S16, the lithium compound can be recovered more efficiently. In other words, the crushing step S51, the hydrochloric acid soaking step S52, and the third filtration step S53 of the separation method M50 can be included as part of the production method M10.

[0112] As described above, by carrying out separation method M50, titanium and lithium contained in lithium titanate can be separated into titanium oxide and lithium chloride, respectively. Therefore, lithium, which is a valuable resource, can be recovered and reused together with titanium.

[0113] Sixth Embodiment A dielectric heating device 10 according to a sixth embodiment of the present invention will be described with reference to Figs. 4 and 5. The dielectric heating device 10 is an example of an apparatus for producing a beryllium solution according to one aspect of the present invention. Fig. 4 is a schematic diagram of the dielectric heating device 10. The dielectric heating device 10 is a heating device that performs the heating step S13 included in the production method M10 shown in Fig. 1 and the heating step S13 included in the separation method M50 shown in Fig. 3. Furthermore, when a hydrochloric acid solution is heated in the dissolving step S14 included in the production method M10, the dielectric heating device 10 can also be used for this heating.

[0114] As explained in the first embodiment, dielectric heating is classified as either high-frequency heating or microwave heating depending on the frequency band of the applied electromagnetic waves. The dielectric heating device 10 is a device that performs microwave heating, out of high-frequency heating and microwave heating, on an object.

[0115] <Configuration of the dielectric heating device> As shown in Fig. 4, the dielectric heating device 10 includes an electromagnetic wave generating unit 11, a waveguide 12, an electromagnetic wave applying unit 13, a container 14, a turntable 15, a stirrer 16, and a thermometer 17, and as shown in Fig. 5, it further includes an isolator 18. The dielectric heating device 10 also includes a control unit not shown in Fig. 4.

[0116] (Electromagnetic wave generating part) The electromagnetic wave generating unit 11 is configured to oscillate electromagnetic waves having a predetermined frequency. The predetermined frequency can be selected appropriately within the microwave band, for example, but in this embodiment, the predetermined frequency is set to 2.45 GHz. The frequency of 2.45 GHz is the same frequency as the electromagnetic waves used in home microwave ovens.

[0117] (waveguide) Waveguide 12 is a cylindrical member made of metal, one end of which is connected to electromagnetic wave generating unit 11 and the other end of which is connected to electromagnetic wave application unit 13, which houses container 14 (described later). That is, waveguide 12 is interposed between electromagnetic wave generating unit 11 and container 14. Waveguide 12 guides the electromagnetic waves generated by electromagnetic wave generating unit 11 from one end to the other end. Waveguide 12 then radiates these electromagnetic waves from the other end into the internal space of electromagnetic wave application unit 13, which houses container 14. That is, waveguide 12 guides the electromagnetic waves generated by electromagnetic wave generating unit 11 from electromagnetic wave generating unit 11 in the direction of container 14.

[0118] (Isolator) 5, an isolator 18 is provided in a midsection of the waveguide 12. The isolator 18 includes a circulator 181, a dummy load 182, and a cooling pipe 183. The circulator 181 is inserted in a midsection of the waveguide 12.

[0119] Circulator 181 has a magnet (made of, for example, ferrite) and has three ports P1 to P3 as shown in Fig. 5. Port P1 is connected to electromagnetic wave generating unit 11 via one section of waveguide 12. Port P2 is connected to electromagnetic wave applying unit 13 via the other section of waveguide 12. Port P3 is provided with a dummy load 182.

[0120] The magnetic field generated by the magnet interacts with the electromagnetic waves passing through circulator 181, causing the electromagnetic waves incident on port P1 to exit port P2 and the electromagnetic waves incident on port P2 to exit port P3. Therefore, circulator 181 couples the electromagnetic waves generated by electromagnetic wave generation unit 11 in the direction of electromagnetic wave application unit 13, and couples the electromagnetic waves reflected in the internal space of electromagnetic wave application unit 13 to dummy load 182.

[0121] The dummy load 182 is made of a material that absorbs electromagnetic waves with a frequency of 2.45 GHz. Therefore, the dummy load 182 absorbs the electromagnetic waves reflected in the internal space of the electromagnetic wave application unit 13 and converts the energy into heat.

[0122] The dummy load 182 is provided with a cooling pipe 183. A configuration is adopted in which a cooled refrigerant (for example, water or air) circulates inside the cooling pipe 183. The cooled refrigerant can remove heat from the dummy load 182, thereby preventing the temperature of the dummy load 182 from rising excessively.

[0123] Circulator 181 configured as described above can couple the electromagnetic waves generated by electromagnetic wave generating unit 11 to electromagnetic wave application unit 13 with almost no loss, and can absorb the electromagnetic waves reflected in the internal space of electromagnetic wave application unit 13. That is, circulator 181 can propagate the electromagnetic waves from electromagnetic wave generating unit 11 toward container 14 with almost no loss, and can absorb the electromagnetic waves propagating from container 14 toward electromagnetic wave generating unit 11. Therefore, it is possible to prevent the electromagnetic waves reflected in the internal space of electromagnetic wave application unit 13 from returning to electromagnetic wave generating unit 11 and adversely affecting the operation of electromagnetic wave generating unit 11.

[0124] (Electromagnetic wave application unit) The electromagnetic wave application unit 13 is a metal box-shaped member with a hollow interior space, and is configured so that the interior space can accommodate the container 14. The electromagnetic wave application unit 13 applies the electromagnetic waves irradiated from the other end of the waveguide 12 to the container 14 and the object to be heated accommodated in the container 14. The electromagnetic wave application unit 13 is configured to confine the electromagnetic waves within the interior space and prevent them from leaking to the outside.

[0125] (container) The container 14 is a dish-shaped container. The shape of the container 14 is such that the powder mixture M of the starting material and sodium hydroxide is P However, the shape is not limited as long as it can accommodate the powder mixture M. P In order to measure the temperature of the container 14, it is preferable that the container 14 has a large opening. Furthermore, when the dissolving step S14 is carried out using the container 14 as it is after the heating step S13, it is preferable that the container 14 has a volume capable of containing a predetermined amount of hydrochloric acid solution.

[0126] In the case where a powdery mixture is obtained by mixing a starting material powder and sodium hydroxide (sodium hydroxide powder in the examples described later) using a mortar, as in the examples described later, the mortar functions as a mixing part. In the case where a powdery mixture is obtained by placing the starting material powder and sodium hydroxide powder in a container 14 and mixing them in the container 14, the container 14 functions as a mixing part.

[0127] The container 14 is preferably made of a material that has high transmittance to the electromagnetic waves (2.45 GHz in this embodiment) generated by the electromagnetic wave generating unit 11. The container 14 is also preferably made of a material that is highly resistant to acids and bases. When the container 14 is made of a material that is highly resistant to acids and bases, the dissolving step S14 can be carried out by pouring a hydrochloric acid solution into the container 14 after carrying out the heating step S13.

[0128] In this embodiment, the container 14 is made of a fluororesin such as polytetrafluoroethylene. However, the material of the container 14 is not limited to a fluororesin, and may be an aromatic polyether ketone resin such as polyether ether ketone, a polyimide resin, or an oxide such as alumina or titanium oxide.

[0129] (rotary table) The turntable 15 is a sample stage provided on the bottom surface of the internal space of the electromagnetic wave application unit 13, and is configured so that the container 14 can be placed on the upper surface. The turntable 15 is circular in plan view, and is configured to rotate at a predetermined speed around its central axis. With this configuration, the container 14 placed on the upper surface of the turntable 15 rotates periodically, so that the powder mixture M P can be heated more uniformly.

[0130] (Starla) The stirrer 16 is a metallic vane-shaped member provided on the ceiling surface of the internal space of the electromagnetic wave application unit 13. It is fixed in a rotatable state relative to the ceiling surface by a support rod connected to the center of the vane-shaped member. The stirrer 16 rotates at a predetermined speed around the support rod as a rotation axis, thereby reflecting the electromagnetic waves generated by the electromagnetic wave generation unit 11 and scattering them in the internal space of the electromagnetic wave application unit 13. With this configuration, the stirrer 16 scatters the electromagnetic waves, so that the powder mixture M P can be heated more uniformly.

[0131] (thermometer) The thermometer 17 is a powder mixture M P The thermometer 17 is a radiation thermometer that measures the temperature of the container 14 by detecting infrared rays emitted by the powder mixture M. P The thermometer 17 is fixed to a part of the side wall of the electromagnetic wave application unit 13 so as to be able to detect infrared rays from the powder mixture M. P A temperature signal representing the temperature of the sensor is output to the control unit.

[0132] (Control unit) The control unit may control the output of the electromagnetic wave generating unit 11 so that the output becomes a predetermined value, or may control the output of the electromagnetic wave generating unit 11 so that the temperature of the temperature signal received from the thermometer 17 becomes a predetermined temperature. Note that this predetermined temperature may be constant over time, or may change over time. In this embodiment, the control unit controls the output of the electromagnetic wave generating unit 11 so that the output value changes over time. An example of an output control pattern is a pattern in which an output of 300 W is maintained for 600 seconds and then the output is set to 0 W.

[0133] In the manufacturing method M10, for example, the dielectric heating device 10 configured as above is used to fill the inner space of the container 14 with the powder mixture M. PThe heating step S13 can be performed by placing the hydrochloric acid solution in the container 14. After the heating step S13 has been performed, the dissolving step S14 can be performed by pouring the hydrochloric acid solution into the container 14. When the dissolving step S14 is performed using the dielectric heating device 10, the hydrochloric acid solution can be heated, which can promote dissolution of the liquid mixture in the hydrochloric acid solution. The hydrochloric acid solution of the liquid mixture is an example of an inorganic solution.

[0134] [First Example] A first example of a manufacturing method M10 using the above-described dielectric heating device 10 will be described with reference to Fig. 6. Fig. 6 is a graph showing the temperature change of the mixture M in an example of the above-described heating step S13. In this example, beryl was used as the starting material.

[0135] In this example, beryl was pulverized using a ball mill in the pulverization and mixing step S12. The particle size of the beryl after the pulverization and mixing step S12 was 150 μm or less. Sodium hydroxide was pulverized for 30 minutes using a mortar. Then, 0.2 g and 2 g of beryl powder and sodium hydroxide powder were taken, respectively, and mixed in a mortar to obtain a powder mixture M. P obtained.

[0136] In this example, in the heating step S13, the powder mixture M P The powder mixture M was placed on a container 14 made of aluminum oxide (alumina: Al2O3) and dielectrically heated in an air atmosphere under normal pressure using a dielectric heating device 10. The output of the dielectric heating device 10 was set to 300 W, and the heating time was set to 8 minutes. By carrying out the heating step S13, the powder mixture M P The mixture melted with dielectric heating, and after 8 minutes, it became a liquid mixture with a milky consistency. Hereinafter, when it is not necessary to distinguish between powder and liquid, the mixture will be simply referred to as "mixture M." In the heating step S13 of this example, the maximum temperature of mixture M was approximately 220°C.

[0137] After the output value was set to 300 W, the temperature of the mixture M continued to indicate 50°C from 0 seconds to approximately 345 seconds. This is because the lower limit of the temperature that can be detected by the thermometer 17 is 50°C.

[0138] In this example, after the liquid mixture is cooled to room temperature, in the dissolving step S14, an aqueous hydrochloric acid solution (HCl: 6 mol / L, 20 cm 3 The liquid mixture was poured into the container under atmospheric conditions at room temperature and normal pressure. As a result, the liquid mixture was completely dissolved in the hydrochloric acid solution (99% beryllium dissolution was confirmed).

[0139] [Second Example] The following describes a second example of the manufacturing method M10 using the above-mentioned dielectric heating device 10. In this example, spodumene (LiAlSi2O6), an example of lithium ore, was used as the starting material.

[0140] In this example, spodumene was pulverized using a ball mill in the pulverization and mixing step S12. The particle size of spodumene after the pulverization and mixing step S12 was 150 μm or less. Sodium hydroxide was pulverized for 30 minutes using a mortar. Then, 0.2 g and 2 g of spodumene powder and sodium hydroxide powder were taken, respectively, and mixed in a mortar to obtain a powder mixture M. P obtained.

[0141] In this example, in the heating step S13, the powder mixture M P The powder mixture M was placed on a container 14 made of aluminum oxide (alumina: Al2O3) and dielectrically heated in an air atmosphere under normal pressure using a dielectric heating device 10. The temperature history due to dielectric heating showed the same tendency as in Figure 6. The output value of the dielectric heating device 10 was set to 300 W, and the heating time was set to 8 minutes. By carrying out the heating step S13, the powder mixture M PThe mixture melted with dielectric heating, and after 8 minutes, it became a liquid mixture with a milky consistency. Hereinafter, when it is not necessary to distinguish between powder and liquid, the mixture will be simply referred to as "mixture M." In the heating step S13 of this example, the maximum temperature of mixture M was approximately 220°C.

[0142] In this example, after the liquid mixture is cooled to room temperature, in the dissolving step S14, an aqueous hydrochloric acid solution (HCl: 6 mol / L, 20 cm 3 The liquid mixture was poured into the container under atmospheric conditions at room temperature and normal pressure. As a result, the liquid mixture dissolved in the hydrochloric acid solution (more than 90% of the lithium was dissolved).

[0143] (Reference example) Furthermore, as a reference example of the heating step S13 included in the manufacturing method M10, sodium hydroxide powder and sodium bicarbonate powder were subjected to dielectric heating. The results are described with reference to Figs. 7 and 8. Fig. 7 is a graph showing the temperature change of sodium hydroxide obtained as a result of dielectrically heating sodium hydroxide powder. Fig. 8 is a graph showing the temperature change of sodium bicarbonate obtained as a result of dielectrically heating sodium bicarbonate powder.

[0144] As in the above-described examples, sodium hydroxide and sodium bicarbonate were each ground in a mortar for 30 minutes. Then, 2 g of each of the sodium hydroxide and sodium bicarbonate was taken and dielectrically heated using the dielectric heating device 10. In this reference example, the output of the dielectric heating device 10 was set to 300 W, and the heating time was set to 10 minutes.

[0145] Referring to FIG. 7, it was found that the sodium hydroxide powder was heated by dielectric heating, and the maximum temperature reached was about 250°C. After the dielectric heating, the sodium hydroxide was melted and in a liquid state. From this result, it was found that in the heating step S13 of the manufacturing method M10, the powder mixture M P It is thought that sodium hydroxide absorbs the energy of the electromagnetic waves used for dielectric heating.

[0146] On the other hand, referring to Figure 8, it was found that the temperature of sodium carbonate powder hardly rose even when dielectric heating was performed. In Figure 8, the temperature of the sodium carbonate was below 50°C, which is the lower limit of detection by thermometer 17. From this result, it is thought that sodium carbonate used in the conventional alkali fusion method hardly absorbs the energy of the electromagnetic waves used in dielectric heating.

[0147] Although a graph is omitted, it was found that when at least one of beryl and spodumene powders was subjected to dielectric heating alone, the temperature of at least one of beryl and spodumene powder hardly rose, just like in the case of sodium carbonate powder. From this result, it is thought that beryl and spodumene not mixed with sodium hydroxide hardly absorb the energy of the electromagnetic waves used for dielectric heating.

[0148] Seventh Embodiment <Beryllium production system> A beryllium production system 20 according to a seventh embodiment of the present invention will be described with reference to FIGS. 9 and 10. FIG. 9 is a schematic diagram of a beryllium solution (BeCl solution) production apparatus 20A constituting part of the beryllium production system 20. FIG. 10(a) is a schematic diagram of a crystallizer 20B, a dehydration apparatus 20C, and an electrolysis apparatus 20D. FIG. 10(b) is a schematic diagram of a modified crystallization treatment tank 31 provided in the crystallizer 20B shown in FIG. 10(a). FIG. 10(c) is a schematic diagram of a modified dryer 33 provided in the dehydration apparatus 20C shown in FIG. 10(a). Each of the crystallizer 20B, the dehydration apparatus 20C, and the electrolysis apparatus 20D constitutes part of the beryllium production system 20. Note that, hereinafter, the beryllium production system 20 will also be simply referred to as the production system 20, and the beryllium solution production apparatus 20A will also be simply referred to as the production apparatus 20A.

[0149] 9 and 10, the production system 20 includes a production apparatus 20A, a crystallizer 20B, a dehydration apparatus 20C, and an electrolysis apparatus 20D, and is an apparatus for carrying out the production method M20 shown in Fig. 2(a). More specifically, the production apparatus 20A is an apparatus for carrying out each step of the production method M10 shown in Fig. 1 except for the removal step S11, the crystallizer 20B and the dehydration apparatus 20C are apparatus for carrying out the dehydration step S21 shown in Fig. 2(a), and the electrolysis apparatus 20D is an apparatus for carrying out the electrolysis step S22 shown in Fig. 2(a).

[0150] In this embodiment, as in the first embodiment, lithium titanate (Li2TiO3), which is an example of a tritium breeding material, and beryllium (Be), which is an example of a neutron multiplier material, with an oxide layer of beryllium oxide (BeO) formed on its surface are used as starting materials. However, the starting materials in the manufacturing apparatus 20A are not limited to lithium titanate (Li2TiO3) and beryllium (Be), which is an example of a tritium breeding material and has an oxide layer of beryllium oxide (BeO) formed on its surface, as exemplified in the first embodiment.

[0151] (Beryllium solution manufacturing equipment 20A) 9, manufacturing apparatus 20A includes pulverizer 21a, feeder F1a, pulverizer 21b, feeder F1b, valves V1 to V15, dielectric heating device 22, filters 23 and 29, containers 24, 26, 27, 28, and 30, and a centrifuge 25. Manufacturing apparatus 20A also includes a control unit not shown in FIG. 9. The control unit controls each of feeders F1a and F1b, valves V1 to V15, and dielectric heating device 22.

[0152] The pulverizer 21a pulverizes the introduced starting materials, lithium titanate and beryllium with an oxide layer formed on their surfaces, into powder. The pulverizer 21a then supplies the lithium titanate and beryllium powder to the feeder F1a. The pulverizer 21a can be appropriately selected from existing pulverizers according to desired specifications. Therefore, a detailed description of the pulverizer 21a will be omitted here. By pulverizing the starting materials using the pulverizer 21a, even if an oxide layer has formed on the surface of beryllium, an example of a neutron multiplier material, the oxide layer can be mechanically destroyed to expose the beryllium that was covered by the oxide layer. Therefore, the rate of melting beryllium together with sodium hydroxide in the heating step S13 can be increased.

[0153] The feeder F1a is controlled by the control unit, and supplies the starting material supplied from the pulverizer 21a to a container 22c of the dielectric heating device 22, which will be described later. The feeder F1a is an example of a raw material supply unit that supplies the starting material to the container 22c.

[0154] The pulverizer 21b pulverizes the input sodium hydroxide into powder. The pulverizer 21b then supplies the sodium hydroxide powder to the feeder F1b. The pulverizer 21b can be appropriately selected from existing pulverizers according to the desired specifications. Therefore, a detailed description of the pulverizer 21b will be omitted here. By pulverizing the sodium hydroxide using the pulverizer 21b, the particle size of the sodium hydroxide can be adjusted to a desired size. As mentioned above, the shape of the sodium hydroxide is not limited to powder. Therefore, the pulverizer 21b can be omitted from the manufacturing apparatus 20A.

[0155] Feeder F1a is controlled by the control unit and supplies the powder of the starting material supplied from pulverizer 21a to container 22c of dielectric heating device 22, which will be described later. Feeder F1a is an example of a material supply unit that supplies the starting material to container 22c. Similarly, feeder F1b is controlled by the control unit and supplies sodium hydroxide powder supplied from pulverizer 21b to container 22c of dielectric heating device 22, which will be described later. Feeder F1b is an example of a hydroxide supply unit that supplies sodium hydroxide to container 22c.

[0156] Dielectric heating device 22 includes electromagnetic wave generating unit 22a, waveguide 22b, container 22c, a stirring mechanism, and a thermometer. Dielectric heating device 22 performs heating step S13 and melting step S14 of manufacturing method M10 shown in FIG.

[0157] The electromagnetic wave generating unit 22a is controlled by the control unit and configured to generate electromagnetic waves having a predetermined frequency. The predetermined frequency can be selected appropriately within the microwave band, for example, but in this embodiment, the predetermined frequency is 2.45 GHz. The frequency of 2.45 GHz is the same frequency as the electromagnetic waves used in home microwave ovens.

[0158] Waveguide 22b is a cylindrical metal member, one end of which is connected to electromagnetic wave generating unit 22a and the other end of which is connected to container 22c. Waveguide 22b guides the electromagnetic waves generated by electromagnetic wave generating unit 22a from one end to the other end and radiates the electromagnetic waves from the other end into the internal space of container 22c. Although not shown in FIG. 9, the isolator shown in FIG. 5 is provided in a midsection of waveguide 22b. In this case, waveguide 12 shown in FIG. 5 can be read as waveguide 22b.

[0159] The container 22c is a box-shaped member that contains the starting material powder and sodium hydroxide powder in its internal space. Like the container 14 shown in FIG. 4, the container 22c is made of an acid-resistant material. The container 22c receives the starting material powder supplied from the pulverizer 21a via the feeder F1a and the sodium hydroxide powder supplied from the pulverizer 21b via the feeder F1b. A stirring mechanism (not shown in FIG. 9) is provided inside the container 22c. The control unit rotates the stirring mechanism, mixing the starting material powder and sodium hydroxide powder supplied to the internal space of the container 22c to form a powdery mixture. Thus, the container 22c is an example of a mixing unit that mixes the starting material powder and sodium hydroxide powder to obtain a powdery mixture. The container 22c may be a tubular container that rotates around its axis, such as a rotary kiln. Furthermore, continuous processing can be performed by combining the rotary kiln with a liquid supply unit (described later).

[0160] A thermometer, not shown in FIG. 9, detects the temperature of the contents (the powdery mixture at this point) contained in the internal space of container 22c and outputs a temperature signal representing that temperature to the control unit. The thermometer may be a non-contact thermometer such as a radiation thermometer, or a contact thermometer such as a thermocouple. Whichever type of thermometer is used, it is preferable that the thermometer be provided in the internal space of container 22c and configured to be able to directly detect the temperature of the contents contained in the internal space.

[0161] The control unit may control the output of the electromagnetic wave generator 22a so that the output reaches a predetermined value, or may control the output of the electromagnetic wave generator 22a so that the temperature indicated by the temperature signal received from the thermometer reaches a predetermined temperature. This predetermined temperature may be constant over time or may change over time. In this embodiment, the control unit controls the output of the electromagnetic wave generator 22a so that the temperature indicated by the temperature signal changes over time according to a predetermined profile. An example of the predetermined temperature profile is a pattern in which the temperature is changed from room temperature to 250°C over five minutes, and then maintained at 250°C for 10 minutes.

[0162] Dielectric heating device 22 configured in this manner performs heating step S13 of manufacturing method M10 shown in FIG. 1, thereby obtaining a liquid mixture containing the starting material and sodium hydroxide.

[0163] Next, an HCl solution is supplied via valve V1. The dissolving step S14 is performed by supplying the HCl solution to container 22c via valve V1. The mechanism for supplying the HCl solution to container 22c via valve V1 functions as a liquid supply unit that supplies an acidic solution to the liquid mixture. In container 22c, the liquid mixture dissolves in the HCl solution to form a beryllium solution (BeCl2 solution) containing lithium. As described above, the liquid that dissolves the liquid mixture containing the starting material and sodium hydroxide is not limited to an acidic solution such as an HCl solution, but may be water. When water is used as this liquid, the dissolving step S14 is performed by supplying water to container 22c via valve V1.

[0164] During the dissolving step S14, the control unit may control the output of the electromagnetic wave generator 22a so that the output reaches a predetermined value, or may control the output of the electromagnetic wave generator 22a so that the temperature indicated by the temperature signal received from the thermometer reaches a predetermined temperature. By performing induction heating during the dissolving step S14, dissolution of the liquid mixture in the HCl solution is promoted. During the dissolving step S14, the control unit may continue to operate the stirring mechanism.

[0165] Valve V2 opens and closes a path between the internal space of container 22c and filter 23, which will be described later. The control unit keeps valve V2 closed while heating step S13 and dissolving step S14 are being performed, and opens valve V2 after heating step S13 and dissolving step S14 are completed. As a result, the beryllium solution containing lithium obtained in heating step S13 is supplied from container 22c to filter 23.

[0166] The filter 23 is configured to pass the liquid phase (i.e., the BeCl2 solution containing LiCl) of the lithium-containing beryllium solution and filter out the solid phase (i.e., titanium oxide). That is, the filter 23 performs the first filtration step S15 of the manufacturing method M10. The filter 23 can be appropriately selected from existing filters according to the desired specifications. Therefore, a detailed description of the filter 23 will be omitted here.

[0167] Valve V3 opens and closes a path between filter 23 and container 24, which will be described later. The control unit opens valve V3 at least during the period in which the beryllium solution containing lithium is being supplied to filter 23. As a result, the BeCl2 solution containing LiCl obtained in the first filtration step S15 is supplied from filter 23 to container 24.

[0168] Container 24 is a box-shaped member with a hollow interior that is acid-resistant and base-resistant. Each of containers 26, 27, 28, and 30, the configuration of which will be described later, is an acid-resistant box-shaped member. NaOH solution is supplied to container 24 via valve V4. The mechanism that supplies NaOH solution to the beryllium solution in container 24 via valve V4 functions as a NaOH solution supply unit that supplies NaOH solution to the beryllium solution.

[0169] The BeCl2 solution containing LiCl and the NaOH solution supplied to the container 24 are mixed in the internal space of the container 24. That is, the sodium hydroxide adding step S16 of the manufacturing method M10 is carried out in the internal space of the container 24. As a result, solid beryllium hydroxide (Be(OH)2) is produced inside the container 24, and liquid LiOH dissolves in the NaOH solution.

[0170] 9, a stirring mechanism for stirring the BeCl2 solution containing LiCl and the NaOH solution may be provided in the internal space of the container 24. Similarly, stirring mechanisms may be provided in the internal spaces of the containers 26, 27, 28, and 30 described below.

[0171] Valve V5 opens and closes a path between the internal space of container 24 and centrifuge 25, which will be described later. The control unit closes valve V5 while sodium hydroxide addition step S16 is being performed, and opens valve V5 after sodium hydroxide addition step S16 is performed. As a result, the NaOH solution containing Be(OH)2 and LiOH obtained in sodium hydroxide addition step S16 is supplied from container 24 to centrifuge 25.

[0172] The centrifuge 25 separates the NaOH solution containing Be(OH)2 and LiOH into a liquid phase (i.e., the NaOH solution containing LiOH) and a solid phase (i.e., Be(OH)2). That is, the centrifuge 25 performs the second filtration step S17 of the manufacturing method M10. The centrifuge 25 can be appropriately selected from existing centrifuges according to the desired specifications. Therefore, a detailed description of the centrifuge 25 will be omitted here. The Be(OH)2 obtained in the second filtration step S17 is introduced into the internal space of a container 26 described below, and the aqueous NaOH solution containing LiOH obtained in the second filtration step S17 is recovered in a recovery line (not shown).

[0173] Also, a filter such as filter 23 may be used instead of centrifuge 25 to separate the liquid phase and the solid phase in the NaOH solution containing Be(OH)2 and LiOH.

[0174] An HCl solution is supplied to the container 26 via a valve V6. The Be(OH)2 and HCl solution supplied to the container 26 are mixed in the internal space of the container 26. That is, the hydrochloric acid adding step S18 of the manufacturing method M10 is carried out in the internal space of the container 26. As a result, a beryllium solution (BeCl2 solution) is produced inside the container 26, in which the produced BeCl2 is dissolved in the HCl solution.

[0175] Valve V7 opens and closes the path between the internal space of container 26 and the internal space of container 27, which will be described later. The control unit closes valve V7 while hydrochloric acid addition step S18 is being performed, and opens valve V7 after hydrochloric acid addition step S18 is completed. As a result, the beryllium solution obtained in hydrochloric acid addition step S18 is supplied from container 26 to container 27.

[0176] An organic compound solution is supplied to the container 27 via a valve V8. The mechanism for supplying the organic compound solution to the container 27 via the valve V8 functions as an organic compound solution supply unit that supplies the organic compound solution to the beryllium chloride solution. This organic compound solution is the organic compound solution described in the first impurity removal step S19 of the manufacturing method M10. Therefore, a description of the organic compound solution will be omitted here.

[0177] The beryllium solution and the organic compound solution supplied to the container 27 are mixed in the internal space of the container 27. That is, the first impurity removal step S19 is carried out in the internal space of the container 27. As a result, the beryllium solution in which the content of the first element is suppressed and the organic compound solution containing the first element are separated into two layers inside the container 27. Because the specific gravity of the beryllium solution exceeds the specific gravity of the organic compound solution, the beryllium solution is located below the organic compound solution.

[0178] Valve V9 opens and closes the path between the internal space of container 27 and a recovery line (not shown). Valve V10 opens and closes the path between the internal space of container 27 and the internal space of container 28 (described later).

[0179] The control unit keeps both valves V9 and V10 closed while the first impurity removal step S19 is being performed. After the first impurity removal step S19 is performed, the control unit first opens only valve V10. As a result, the beryllium solution with a reduced content of the first element obtained by the first impurity removal step S19 is supplied from container 27 to container 28. Thereafter, the control unit closes valve V10 and opens valve V9. As a result, the organic compound solution containing the first element obtained by the first impurity removal step S19 is recovered in the recovery line.

[0180] Sodium bicarbonate is supplied to the container 28 via a valve V11. The mechanism for supplying sodium bicarbonate to the container 28 via the valve V11 functions as a sodium bicarbonate supply unit that supplies sodium bicarbonate to the beryllium chloride solution. This sodium bicarbonate is the same as that described in the second impurity removal step S20 of the manufacturing method M10. Therefore, a description of the sodium bicarbonate will be omitted here.

[0181] The beryllium solution and sodium bicarbonate supplied to the container 28 are mixed in the internal space of the container 28. That is, the second impurity removal step S20 is carried out in the internal space of the container 28. As a result, the hydroxide of the second element precipitates inside the container 28, and the content of the second element in the beryllium hydroxide (Be(OH)2) solution is suppressed.

[0182] Valve V12 opens and closes a path between the internal space of container 28 and a filter, which will be described later. The control unit closes valve V12 while the second impurity removal step S20 is being performed, and opens valve V12 after the second impurity removal step S20 is completed. As a result, the beryllium hydroxide solution obtained in the second impurity removal step S20, which contains the hydroxide of the second element, is supplied from container 28 to filter 29.

[0183] Filter 29 is configured to pass the liquid phase (i.e., the beryllium hydroxide solution) of the beryllium hydroxide solution containing the hydroxide of the second element and to filter the solid phase (i.e., the hydroxide of the second element). Filter 29 can be appropriately selected from existing filters according to the desired specifications. Therefore, a detailed description of filter 29 will be omitted here.

[0184] Valve V13 opens and closes the path between filter 29 and container 30, which will be described later. The control unit opens valve V13 at least during the period in which the beryllium hydroxide solution containing the hydroxide of the second element is being supplied to filter 29. As a result, the beryllium hydroxide solution obtained in the second impurity removal step S20, in which the content of the second element is reduced, is supplied from filter 29 to container 30.

[0185] A beryllium hydroxide solution is supplied to the container 30 via a valve V13, and an HCl solution is supplied via a valve V14. The Be(OH)2 solution and the HCl solution supplied to the container 30 are mixed in the internal space of the container 30. As a result, a beryllium solution (BeCl2 solution) is produced inside the container 30, in which the produced BeCl2 is dissolved in the HCl solution.

[0186] Valve V15 opens and closes the path between the container 30 and a crystallization treatment tank 31 of a crystallizer 20B, which will be described later. The control unit closes valve V15 at least while the HCl solution is being supplied to the container 30, and opens valve V15 after the Be(OH)2 solution and the HCl solution supplied to the container 30 are sufficiently mixed. As a result, the beryllium solution (BeCl2 solution) is supplied from the container 30 to the crystallization treatment tank 31.

[0187] (Crystallizer 20B) As shown in Figure 10(a), the crystallizer 20B includes a crystallization treatment tank 31, a chiller C, a pump P, a condensate tank, and valves V16 and V17. The crystallizer 20B also includes a control unit (not shown in Figure 10(a)). The control unit controls each of the crystallization treatment tank 31, the chiller C, the pump P, and the valves V16 and V17.

[0188] The crystallization treatment tank 31 comprises an inner tank and an outer tank. Warm water is supplied to the inner space of the outer tank via a valve V16. A beryllium solution (BeCl solution) produced by the manufacturing apparatus 20A is supplied to the inner space of the inner tank. The above-mentioned warm water heats the beryllium solution and HCl solution contained in the inner tank. The use of warm water is an example of a heating means employing an external heating method.

[0189] The chiller C, condensate tank, and pump P make up the reduced pressure dehydration system. The pump P evacuates the internal space of the inner tank. The chiller C cools the gas exhausted from the internal space of the inner tank. The condensate tank stores the condensate that has been liquefied by being cooled by the chiller C.

[0190] The crystallizer 20B configured in this manner is capable of crystallizing beryllium chloride. The crystallized beryllium chloride is supplied from the crystallization treatment tank 31 via the valve V17 to the centrifugal separator 32, which will be described later.

[0191] 10(b), the crystallization treatment tank 31 may be provided with an electromagnetic wave generator 31a and a waveguide 31b instead of the valve V16 for supplying hot water. The electromagnetic wave generator 31a and the waveguide 31b are configured similarly to the electromagnetic wave generator 22a and the waveguide 22b shown in FIG. 9, respectively, and are an example of an induction heating device.

[0192] As described above, the heating means for heating the beryllium solution and the HCl solution in the crystallizer 20B may be an external heating system as shown in Fig. 10(a) or an induction heating system as shown in Fig. 10(b). From the viewpoint of energy efficiency, it is preferable to employ an induction heating system.

[0193] (Anhydrous equipment 20C) As shown in Fig. 10(a), the dehydration apparatus 20C includes a centrifuge 32 and a dryer 33. The dehydration apparatus 20C also includes a control unit not shown in Fig. 10(a). The control unit controls each of the centrifuge 32 and the dryer 33.

[0194] The beryllium chloride crystallized by the crystallizer 20B is dehydrated using a centrifuge 32. The dehydrated beryllium chloride is then dehydrated using a dryer 33. An example of the dryer 33 is a hot air generating mechanism that generates hot air, and the hot air generated by the hot air generating mechanism is used to heat and dehydrate the beryllium chloride. In other words, the crystallizer 20B and the dehydration device 20C are examples of the dehydration device described in the claims, and are capable of carrying out the dehydration step S21 of the production method M20 shown in FIG. 2. The hot air is an example of a heating means that employs an external heating method.

[0195] The dryer 33 may include an electromagnetic wave generating unit 33a and a waveguide 33b (see FIG. 10(c)) instead of the hot air generating mechanism that generates hot air. The electromagnetic wave generating unit 33a and the waveguide 33b are configured similarly to the electromagnetic wave generating unit 22a and the waveguide 22b shown in FIG. 9, respectively, and are an example of an induction heating device.

[0196] As described above, the heating means for heating beryllium chloride in the dehydration apparatus 20C may be an external heating method as shown in (a) of Figure 10, or an induction heating method as shown in (c) of Figure 10. From the viewpoint of energy efficiency, it is preferable to employ an induction heating method.

[0197] (Electrolyzer 20D) As shown in Fig. 10(a), the electrolysis device 20D includes an electrolysis furnace 34a, a power supply 34b, an anode 34c, a cathode 34d, and a feeder F2. The electrolysis furnace 34a also includes a heater (not shown in Fig. 10(a)). The electrolysis device 20D also includes a control unit (not shown in Fig. 10(a)). The control unit controls each of the power supply 34b, the heater, and the feeder F2.

[0198] Anhydrous beryllium chloride produced by the dehydration device 20C is supplied into the electrolytic furnace 34a. Sodium chloride (NaCl) is also supplied into the electrolytic furnace 34a via a feeder F2.

[0199] The electrolytic furnace 34a, which contains beryllium chloride and sodium chloride, is heated using a heater. As a result, the beryllium chloride and sodium chloride melt. The melting point of the electrolytic bath can be lowered by using a binary bath containing beryllium chloride and sodium chloride. The temperature of the electrolytic furnace 34a when heated can be appropriately set within a range exceeding the melting point of the binary bath. An example of the temperature of the electrolytic furnace 34a is 350°C.

[0200] The anode 34c is an electrode made of, for example, carbon, and the cathode 34d is an electrode made of, for example, nickel.

[0201] While the binary bath is in a molten state, the control unit uses power supply 34b to apply a current between anode 34c and cathode 34d, causing electrolysis of the binary bath and producing metallic beryllium on the surface of cathode 34d.

[0202] As described above, the electrolysis device 20D can perform the electrolysis step S22 of the manufacturing method M20 shown in FIG.

[0203] Other Embodiments In the seventh embodiment described above, a beryllium production system 20 using the production apparatus 20A, the crystallization apparatus 20B, and the dehydration apparatus 20C, which performs the production method M20, has been described.

[0204] However, the scope of the present invention includes not only the beryllium production system 20, but also a beryllium hydroxide production system that implements the beryllium hydroxide production method M30, and a beryllium oxide production system that implements the beryllium oxide production method M40.

[0205] The beryllium hydroxide manufacturing system includes manufacturing apparatus 20A shown in Fig. 9 and a neutralization apparatus that produces beryllium hydroxide by neutralizing the beryllium chloride solution produced by manufacturing apparatus 20A with a base. The neutralization apparatus can be composed of components corresponding to vessel 24, valves V4 and V5, and centrifuge 25 shown in Fig. 9, for example. Furthermore, ammonia may be used as the base used for neutralization instead of sodium hydroxide.

[0206] The beryllium oxide production system includes the production apparatus 20A shown in Fig. 9 and a third heating device that produces beryllium oxide by heating the beryllium chloride solution produced by the production apparatus 20A. The third heating device is not limited to, but may be, for example, an electric furnace.

[0207] Furthermore, in the sections (Modification of the Beryllium Solution Manufacturing Method) and (Method for Manufacturing Lithium Solution), it was explained that when beryllium ore (e.g., beryl) or lithium ore (e.g., spodumene) is used as the starting material, the sodium hydroxide adding step S16, the second filtration step S17, and the hydrochloric acid adding step S18 can be omitted. Therefore, when manufacturing apparatus 20A is used and beryllium ore or lithium ore is used as the starting material, the configuration for performing each of the sodium hydroxide adding step S16, the second filtration step S17, and the hydrochloric acid adding step S18 can be omitted. In other words, the beryllium solution or lithium solution supplied through valve V3 and obtained in the first filtration step S15 can be supplied directly to container 27.

[0208] [Eighth and Ninth Embodiments] A method M70 for producing lithium hydroxide (LiOH) according to an eighth embodiment of the present invention and a method M80 for producing lithium carbonate (Li2CO3) according to a ninth embodiment of the present invention will be described with reference to Fig. 11. (a) and (b) of Fig. 11 are flowcharts of the method M70 for producing lithium hydroxide and the method M80 for producing lithium carbonate, respectively.

[0209] Both the lithium hydroxide production method M70 and the lithium carbonate production method M80 use a solution containing lithium hydroxide, which is separated as a liquid phase in the second filtration step S17. Moreover, which of the lithium hydroxide production method M70 and the lithium carbonate production method M80 to carry out can be determined appropriately according to the priority at that time.

[0210] (Lithium hydroxide manufacturing method M70) 11(a), the lithium hydroxide manufacturing method M70 includes a drying step S71. The drying step S71 is a step of evaporating the solution separated in the second filtration step S17 and drying the precipitated lithium hydroxide. By carrying out the lithium hydroxide manufacturing method M70, solid lithium hydroxide can be obtained.

[0211] (Lithium carbonate manufacturing method M80) As shown in FIG. 11(b), a lithium carbonate manufacturing method M80 includes a carbon dioxide gas introducing step S81, a fourth filtration step S82, and a drying step S83.

[0212] The carbon dioxide gas introducing step S81 is a step of introducing carbon dioxide gas into the solution separated in the second filtration step S17, thereby precipitating lithium carbonate in the solution.

[0213] The fourth filtration step S82 is a step carried out after the carbon dioxide gas introduction step S81. The fourth filtration step S82 is a step of separating lithium carbonate precipitated in the solution from the solution using a filter.

[0214] The drying step S83 is a step carried out after the fourth filtration step S82. The drying step S83 is a step of drying the lithium carbonate separated in the fourth filtration step S82.

[0215] By carrying out the lithium carbonate production method M80, solid lithium carbonate can be obtained.

[0216] (summary) As described above, solid lithium hydroxide or solid lithium carbonate can be produced by carrying out lithium hydroxide production method M70 or lithium carbonate production method M80 using the solution containing lithium hydroxide separated as a liquid phase in second filtration step S17. Therefore, the lithium hydroxide separated as a liquid phase in second filtration step S17 can be recovered as a resource without being wasted.

[0217] It should be noted that each of the lithium hydroxide production method M70 and the lithium carbonate production method M80 can be included as part of the production method M10, similar to the separation method M50.

[0218] Tenth Embodiment A method M90 for producing lithium carbonate (Li2CO3) according to a tenth embodiment of the present invention will be described with reference to Fig. 12. Fig. 12 is a flowchart of the production method M90. In this embodiment, spodumene (LiAlSi2O6), an example of lithium ore, is used as a starting material.

[0219] As shown in FIG. 12, the manufacturing method M90 includes a pulverizing / mixing step S12, a heating step S13, a dissolving step S14, a first filtration step S15, a sodium hydroxide adding step S16, a second filtration step S17, a carbon dioxide gas introducing step S91, a separation step S92, and a drying step S93.

[0220] The steps from the pulverizing and mixing step S12 to the second filtration step S17 in manufacturing method M90 are the same as the steps from the pulverizing and mixing step S12 to the second filtration step S17 in manufacturing method M10, except that the starting material is spodumene. Therefore, in this embodiment, a detailed description of the steps from the pulverizing and mixing step S12 to the second filtration step S17 will be omitted.

[0221] In this embodiment, sodium hydroxide (NaOH) is used as the hydroxide mixed with the starting materials in the pulverizing and mixing step S12, and hydrochloric acid is used as the acid solution used in the dissolving step S14.

[0222] By carrying out the dissolving step S14, an acid solution containing lithium, aluminum, and silicon ions contained in the spodumene and sodium chloride (NaCl) is obtained.

[0223] By carrying out the first filtration step S15, the silicic acid (H2SiO3) contained in the solid phase can be separated.

[0224] Furthermore, by carrying out the sodium hydroxide addition step S16 and the second filtration step S17, aluminum hydroxide (Al(OH)3) contained in the solid phase can be separated. Furthermore, if a trace amount of iron (Fe) is present in the starting material, the iron can be separated as iron hydroxide (Fe(OH)3) contained in the solid phase. As a result, a sodium hydroxide solution containing lithium hydroxide (LiOH) and sodium chloride (NaCl) is obtained.

[0225] The carbon dioxide gas introducing step S91 is the same step as the carbon dioxide gas introducing step S81 included in the lithium carbonate manufacturing method M80 shown in Fig. 11(b). Therefore, in this embodiment, the description of the carbon dioxide gas introducing step S91 will be omitted. By performing the carbon dioxide gas introducing step S91, a liquid phase containing lithium carbonate (Li2CO3), sodium chloride, and sodium carbonate (Na2CO3) is obtained.

[0226] The separation step S92 is a step of separating lithium carbonate (Li2CO3) from a liquid phase containing lithium carbonate (Li2CO3), sodium chloride, and sodium carbonate (Na2CO3). In the separation step S92, the liquid phase containing lithium carbonate, sodium chloride, and sodium carbonate is concentrated under reduced pressure to obtain a suspension in which lithium carbonate is dispersed. Such a suspension is also called a slurry. Note that the concentration under reduced pressure is preferably carried out at a temperature of 70°C or lower.

[0227] Furthermore, in a separation step S92, the suspension is centrifuged. By performing centrifugation, the precipitated lithium carbonate can be precipitated. Therefore, lithium carbonate contained in the solid phase can be separated from sodium chloride and sodium carbonate contained in the liquid phase.

[0228] The drying step S93 is the same step as that included in the lithium carbonate manufacturing method M80 shown in FIG. 11(b), and is a step of drying the lithium carbonate separated in the separation step S92.

[0229] As described above, by carrying out the lithium carbonate manufacturing method M90, solid lithium carbonate can be obtained using spodumene as a starting material.

[0230] <Modification of Manufacturing Method M90> In this embodiment, spodumene was used as the starting material. However, the starting material used in manufacturing method M90 is not limited to spodumene. Examples of starting materials include oxide minerals (e.g., bauxite) and artificial composite oxides (e.g., yttria-stabilized zirconia (YSZ) and cordierite). Bauxite contains aluminum oxide hydrate (Al2O3·2H2O) and aluminum (Al). YSZ contains zirconia (zirconium oxide, ZrO2) and yttria (yttrium oxide, YO3). Cordierite contains magnesium oxide (MgO), aluminum oxide (Al2O3), and silicon oxide (SiO2).

[0231] Even when these starting materials are used, manufacturing method M90 can be suitably used. As described in the explanation of manufacturing method M10, the hydroxide mixed with the starting materials in the pulverizing and mixing step S12 may be sodium hydroxide or potassium hydroxide. Furthermore, the liquid in which the liquid mixture is dissolved in the dissolving step S14 may be an acid solution such as hydrochloric acid, sulfuric acid, or aqua regia, or may be water.

[0232] As described above, by carrying out one variation of manufacturing method M90, a solution (e.g., an aluminum solution) in which inorganic substances constituting the oxide mineral or composite oxide are dissolved can be obtained using an oxide mineral or composite oxide as a starting material. When the oxide mineral or composite oxide contains multiple inorganic substances (e.g., aluminum, precious metals, etc.), a solution in which two or more of these inorganic substances are dissolved can be obtained.

[0233] Eleventh Embodiment A method M100 for producing lithium carbonate (Li2CO3) according to an eleventh embodiment of the present invention will be described with reference to Fig. 13. Fig. 13 is a flowchart of the production method M100. In this embodiment, spodumene (LiAlSi2O6), an example of lithium ore, is used as a starting material.

[0234] As shown in FIG. 13, the manufacturing method M100 includes a pulverizing and mixing step S12, a heating step S13, a dissolving step S14, a first filtration step S15, a sodium bicarbonate adding step S1006, a fifth filtration step S1007, a separation step S1008, and a drying step S1009.

[0235] The pulverizing and mixing step S12 to the first filtration step S15 in the manufacturing method M100 are the same as the pulverizing and mixing step S12 to the first filtration step S15 in the manufacturing method M90, and therefore, in this embodiment, detailed description of the pulverizing and mixing step S12 to the first filtration step S15 will be omitted.

[0236] The sodium bicarbonate addition step S1006 and the fifth filtration step S1007, which are performed after the first filtration step S15, correspond to the sodium hydroxide addition step S16 and the second filtration step S17 included in the manufacturing method M90. By performing the sodium bicarbonate addition step S1006 and the fifth filtration step S1007, aluminum hydroxide (Al(OH)3) contained in the solid phase can be separated. Furthermore, when a trace amount of iron (Fe) is present in the starting material, the iron can be separated as iron hydroxide (Fe(OH)3) contained in the solid phase. As a result, a sodium hydroxide solution containing lithium carbonate, sodium chloride (NaCl), sodium carbonate (Na2CO3), and sodium bicarbonate (NaHCO3) is obtained.

[0237] The separation step S1008 and drying step S1009 of manufacturing method M100 correspond to the separation step S92 and drying step S93 of manufacturing method M90. In the separation step S1008 of manufacturing method M100, similar to the separation step S92 of manufacturing method M90, a sodium hydroxide solution containing lithium carbonate, sodium chloride (NaCl), sodium carbonate (NaCO), and sodium bicarbonate (NaHCO) is concentrated under reduced pressure and centrifuged to obtain a suspension in which lithium carbonate is dispersed. However, in the separation step S1008, methanol is added to the sodium hydroxide solution during the reduced pressure concentration and centrifugation. This allows sodium bicarbonate, which has lower water solubility than sodium chloride and sodium carbonate, to be dissolved in the liquid phase.

[0238] The drying step S1009 is the same as the drying step S93 in the manufacturing method M90, and therefore a description thereof will be omitted here.

[0239] As described above, by carrying out the lithium carbonate manufacturing method M100, solid lithium carbonate can be obtained using spodumene as a starting material.

[0240] [Twelfth embodiment] A lithium hydroxide (LiOH) manufacturing method M110 according to a twelfth embodiment of the present invention will be described with reference to Fig. 14. Fig. 14 is a flowchart of the manufacturing method M110. In this embodiment, spodumene (LiAlSi2O6), an example of lithium ore, is used as a starting material.

[0241] As shown in FIG. 14, the manufacturing method M110 includes a grinding and mixing step S12, a heating step S13, a dissolving step S14, a first filtration step S15, a third impurity removal step S1106, a first extraction step S1107, a sulfuric acid addition step S1108, a second extraction step S1109, a calcium hydroxide addition step S1110, a sixth filtration step S1111, a separation step S1112, and a drying step S1113.

[0242] The pulverizing and mixing step S12 to the heating step S13 in the manufacturing method M110 are the same as the pulverizing and mixing step S12 to the heating step S13 in the manufacturing method M10, so in this embodiment, detailed description of the pulverizing and mixing step S12 to the heating step S13 will be omitted.

[0243] The dissolving step S14 in manufacturing method M110 is the same as the dissolving step S14 in manufacturing method M10, except that the acid solution used is sulfuric acid (H2SO4). Therefore, in this embodiment, a detailed description of the dissolving step S14 will be omitted. By performing the dissolving step S14, an acid solution containing lithium, aluminum, and silicon ions contained in the spodumene and sodium (Na) ions derived from sodium hydroxide is obtained.

[0244] By carrying out the first filtration step S15, the silicic acid (H2SiO3) contained in the solid phase can be separated.

[0245] The third impurity removal step S1106 is the same as the first impurity removal step S19 in manufacturing method M10. However, the third impurity removal step S1106 differs from the first impurity removal step S19 in that a mixture of di(2-ethylhexyl) phosphoric acid (D2EHPA) and tri-n-butyl phosphate (TBP) is used as the organic compound, and sodium hydroxide (NaOH) is further mixed with the organic compound. By performing the third impurity removal step S1106, lithium is adsorbed to D2EHPA and TBP. That is, lithium is contained in the organic layer. On the other hand, aluminum, silicon, and sodium are not adsorbed to D2EHPA and TBP, but are contained in the aqueous layer.

[0246] The first extraction step S1107 is a step of extracting an organic layer from the solution obtained by carrying out the third impurity removal step S1106.

[0247] The sulfuric acid addition step S1108 is a step of adding an aqueous solution of sulfuric acid to the organic layer obtained by performing the first extraction step S1107. By performing the sulfuric acid addition step S1108, lithium adsorbed to D2EHPA and TBP forms lithium sulfide (Li2SO4) and migrates from the organic layer to the aqueous layer. Therefore, the aqueous layer can also be said to be an aqueous sulfuric acid solution containing lithium.

[0248] The second extraction step S1109 is a step of extracting an aqueous layer containing lithium sulfide from the solution obtained by carrying out the sulfuric acid addition step S1108.

[0249] The calcium hydroxide addition step S1110 is a step of adding calcium hydroxide (Ca(OH)2) to the aqueous layer (sulfuric acid aqueous solution containing lithium) obtained by carrying out the second extraction step S1109. By carrying out the calcium hydroxide addition step S1110, calcium precipitates by forming calcium sulfate (CaSO4), which is a sulfate salt, and lithium dissolves by ionizing with hydroxide ions.

[0250] The sixth filtration step S1111 is a step of separating the solid phase and liquid phase contained in the lithium-containing aqueous solution obtained in the calcium hydroxide addition step S1110 using a filter. The solid phase contains calcium sulfate. The liquid phase contains hydroxide ions and ionized lithium.

[0251] The separation step S1112 and drying step S1113 of production method M110 correspond to the separation step S92 and drying step S93 of production method M90. In separation step S1112, as in separation step S92, a solution containing ionized lithium together with hydroxide ions is subjected to vacuum concentration and centrifugation. By carrying out separation step S1112, a suspension in which lithium hydroxide is dispersed is obtained. Note that the drying step S1113 is the same as the drying step S93 of production method M90, and therefore a description thereof will be omitted here.

[0252] As described above, by carrying out the lithium hydroxide production method M110, solid lithium hydroxide can be obtained using spodumene as a starting material.

[0253] Note that, by subjecting the aqueous layer containing lithium sulfide obtained by carrying out the second extraction step S1109 to a separation step and a drying step similar to the separation step S1112 and the drying step S1113, solid lithium sulfide can be obtained.

[0254] [Thirteenth embodiment] A method M120 for producing lithium carbonate (Li2CO3) according to a thirteenth embodiment of the present invention will be described with reference to Fig. 15. Fig. 15 is a flowchart of the production method M120. In this embodiment, spodumene (LiAlSi2O6), an example of lithium ore, is used as a starting material.

[0255] As shown in FIG. 15, the manufacturing method M120 includes a pulverizing and mixing step S1202, a heating step S1203, a dissolving step S1204, a first filtration step S1205, a carbon dioxide gas introducing step S1206, a separation step S1208, and a drying step S1209.

[0256] The pulverizing and mixing step S1202 and the heating step S1203 in the manufacturing method M120 are the same as the pulverizing and mixing step S12 and the heating step S13 in the manufacturing method M90, so in this embodiment, detailed descriptions of the pulverizing and mixing step S1202 and the heating step S1203 will be omitted.

[0257] The dissolving step S1204 is a step of dissolving the liquid mixture obtained in the heating step S1203 in water (HO). By carrying out the dissolving step S1204, an aqueous sodium hydroxide solution containing dissolved lithium (Li) and silicon (Si) and containing precipitated aluminum hydroxide is obtained.

[0258] The first filtration step S1205 is a step of separating the solid and liquid phases contained in the aqueous sodium hydroxide solution obtained in the dissolving step S1204 using a filter. The solid phase contains aluminum hydroxide. The liquid phase is an aqueous sodium hydroxide solution in which lithium (Li) and silicon (Si) are dissolved.

[0259] The carbon dioxide gas introducing step S1206 is a step of introducing carbon dioxide gas into the aqueous sodium hydroxide solution separated in the first filtration step S1205. By carrying out the carbon dioxide gas introducing step S1206, lithium and sodium form carbonates, lithium carbonate and sodium carbonate, respectively. Silicon forms silicate ions.

[0260] The separation step S1208 and drying step S1209 of manufacturing method M120 correspond to the separation step S92 and drying step S93 of manufacturing method M90. In separation step S1208, similar to separation step S92, a solution containing lithium carbonate, sodium carbonate, and silicate ions is subjected to vacuum concentration and centrifugation. By carrying out separation step S1208, a suspension in which lithium carbonate is dispersed is obtained. Note that the drying step S1209 is the same as the drying step S93 of manufacturing method M90, and therefore a description thereof will be omitted here.

[0261] As described above, by carrying out the lithium carbonate manufacturing method M120, solid lithium carbonate can be obtained using spodumene as a starting material, even when water is used in the dissolving step S1204 without using an acid solution.

[0262] [Fourteenth embodiment] A lithium hydroxide (LiOH) manufacturing method M130 according to a fourteenth embodiment of the present invention will be described with reference to Fig. 16. Fig. 16 is a flowchart of the manufacturing method M130. In this embodiment, spodumene (LiAlSi2O6), an example of lithium ore, is used as a starting material.

[0263] As shown in FIG. 16, manufacturing method M130 includes a grinding and mixing step S1202, a heating step S1203, a dissolving step S1204, a first filtration step S1205, a fourth impurity removal step S1306, a first extraction step S1107, a sulfuric acid addition step S1108, a second extraction step S1109, a calcium hydroxide addition step S1110, a sixth filtration step S1111, a separation step S1112, and a drying step S1113.

[0264] The pulverizing and mixing step S1202 to the first filtration step S1205 in the manufacturing method M130 are the same as the pulverizing and mixing step S1202 to the first filtration step S1205 in the manufacturing method M120. Therefore, in this embodiment, detailed description of the pulverizing and mixing step S1202 to the first filtration step S1205 will be omitted.

[0265] The fourth impurity removal step S1306 is the same as the third impurity removal step S1106 in the manufacturing method M110. However, the fourth impurity removal step S1306 differs from the third impurity removal step S1106 in that a mixture of thenoyltrifluoroacetone (TTA) and tributyl phosphate (TBP) is used as the organic substance, and hydrochloric acid (HCl) is further mixed with the organic substance. By performing the fourth impurity removal step S1306, lithium is adsorbed to TTA and TBP. That is, lithium is contained in the organic layer. On the other hand, aluminum, silicon, and sodium are not adsorbed to TTA and TBP and are contained in the aqueous layer.

[0266] The first extraction step S1107 to the drying step S1113 in the manufacturing method M130 are the same as the first extraction step S1107 to the drying step S1113 in the manufacturing method M110. Therefore, in this embodiment, detailed description of the first extraction step S1107 to the drying step S1113 will be omitted.

[0267] As described above, by carrying out the lithium hydroxide manufacturing method M130, solid lithium hydroxide can be obtained using spodumene as a starting material, even when water is used in the dissolution step S1204 without using an acid solution.

[0268] Note that, by subjecting the aqueous layer containing lithium sulfide obtained by carrying out the second extraction step S1109 to a separation step and a drying step similar to the separation step S1112 and the drying step S1113, solid lithium sulfide can be obtained.

[0269] Fifteenth Embodiment A nickel compound manufacturing method M140 according to a fifteenth embodiment of the present invention will be described with reference to FIG. 17. FIG. 17 is a flowchart of the manufacturing method M140. In this embodiment, nickel sludge is used as the starting material. Nickel sludge is a form of metal scrap and is slag produced when refining nickel. Thus, in the manufacturing method M140, metal scrap can be used as the starting material. Note that nickel sludge contains elements other than nickel (Ni) (e.g., fluorine (F) and sulfur (S)). Therefore, nickel sludge is an example of a nickel compound. However, the starting material used in the manufacturing method M140 is not limited to nickel sludge, and may be a metal produced in a manufacturing process or processing process for machinery or electronic components, or a compound containing such a metal.

[0270] In manufacturing method M140, instead of dissolving the nickel contained in nickel sludge in a solution (an acid solution or water as a solvent), elements other than nickel are dissolved in the solution. By dissolving elements other than nickel in the solution in this way, the purity of the nickel remaining as a solid can be increased. Therefore, manufacturing method M140 can also be said to be a method for purifying nickel compounds.

[0271] As shown in FIG. 17, the manufacturing method M140 includes a pulverizing and mixing step S1402, a heating step S1403, a dissolving step S1404, and a first filtering step S1405.

[0272] The pulverizing and mixing step S1402 corresponds to the pulverizing and mixing step S12 in the manufacturing method M10. That is, the pulverizing and mixing step S1402 is a step in which the starting material is pulverized and then mixed with hydroxide powder. In this embodiment, sodium hydroxide (NaOH) is used as the hydroxide. However, the hydroxide is not limited to sodium hydroxide and may be potassium hydroxide (KOH). In this way, the pulverizing and mixing step S1402 is the same as the pulverizing and mixing step S12 except that the starting material is nickel sludge. Therefore, in this embodiment, a detailed description of the pulverizing and mixing step S1402 will be omitted.

[0273] The heating step S1403, the dissolving step S1404, and the first filtration step S1405 are respectively similar to the heating step S13, the dissolving step S14, and the first filtration step S15 of manufacturing method M10, and therefore, in this embodiment, detailed descriptions of the heating step S1403, the dissolving step S1404, and the first filtration step S1405 will be omitted.

[0274] In the dissolving step S1404, water is used as the liquid for dissolving the liquid mixture obtained in the heating step S1403. In this embodiment, the sodium hydroxide contained in the liquid mixture dissolves in water, and therefore the solution obtained in the dissolving step S1404 is an aqueous sodium hydroxide solution containing the starting material. By performing the dissolving step S1404, the fluorine and sulfur contained in the nickel sludge are dissolved in the aqueous sodium hydroxide solution.

[0275] By carrying out the first filtration step S1405, nickel sludge constituting the solid phase is separated from the sodium hydroxide solution containing fluorine and sulfur contained in the liquid phase. By recovering the solid phase, nickel sludge having a reduced concentration of impurities such as fluorine and sulfur compared to that of the starting material can be obtained.

[0276] As described above, nickel sludge can be purified by carrying out the nickel compound production method M140.

[0277] The production method M140 can also be carried out again on the solid phase obtained by carrying out the first filtration step S1405 (i.e., nickel sludge that has been purified once). By repeatedly carrying out the production method M140 two or more times, the purity of nickel in the obtained nickel sludge can be further increased.

[0278] Sixteenth Embodiment An iron separation method M150 according to a sixteenth embodiment of the present invention will be described with reference to Fig. 18. Fig. 18 is a flowchart of the separation method M150. In this embodiment, ferriite (FeWO4) is used as a starting material. Ferriite is an example of a tungstate mineral.

[0279] As shown in FIG. 18, the separation method M150 includes a pulverizing and mixing step S1502, a heating step S1503, a dissolving step S1504, a first filtration step S1505, a hydrochloric acid immersion step S1552, and a third filtration step S1553.

[0280] The pulverizing and mixing step S1502 corresponds to the pulverizing and mixing step S12 in the manufacturing method M10. That is, the pulverizing and mixing step S1502 is a step in which the starting material is pulverized and then mixed with hydroxide powder. Note that, in this embodiment, the form of sodium hydroxide is not limited to powder. In this embodiment, sodium hydroxide (NaOH) is used as the hydroxide. In this manner, the pulverizing and mixing step S1502 is the same as the pulverizing and mixing step S12 except that the starting material is ferrite. Therefore, in this embodiment, a detailed description of the pulverizing and mixing step S1502 will be omitted.

[0281] The heating step S1503, the dissolving step S1504, and the first filtration step S1505 are respectively similar to the heating step S13, the dissolving step S14, and the first filtration step S15 of manufacturing method M10. Therefore, in this embodiment, detailed descriptions of the heating step S1503, the dissolving step S1504, and the first filtration step S1505 will be omitted.

[0282] In the dissolving step S1504, water is used as the liquid for dissolving the liquid mixture obtained in the heating step S1503. However, the liquid used in the dissolving step S1504 is not limited to water, and may be an acid solution (e.g., a hydrochloric acid solution or a sulfuric acid solution). In this embodiment, the sodium hydroxide contained in the liquid mixture dissolves in water, so the solution obtained in the dissolving step S1504 is an aqueous sodium hydroxide solution containing the starting material. By performing the dissolving step S1504, most (e.g., 90% or more) of the tungsten (W) contained in the ferrous iron ore dissolves in the aqueous sodium hydroxide solution. Therefore, the solid phase contains iron oxide produced by the dissolution of tungsten from the ferrous iron ore.

[0283] By carrying out the first filtration step S1505, iron oxide constituting the solid phase is obtained.

[0284] The hydrochloric acid soaking step S1552 and the third filtration step S1553 are respectively the same as the hydrochloric acid soaking step S52 and the third filtration step S53 in the titanium and lithium separation method M50, and therefore, in this embodiment, detailed description of the hydrochloric acid soaking step S1552 and the third filtration step S1553 will be omitted.

[0285] By carrying out the hydrochloric acid immersion step S1552, the iron contained in the iron oxide dissolves in the hydrochloric acid solution in the form of iron chloride, and therefore, the hydrochloric acid solution after carrying out the hydrochloric acid immersion step S1552 contains iron chloride contained in the liquid phase.

[0286] As described above, by carrying out the iron separation method M150, it is possible to separate tungsten and iron contained in ferrierite.

[0287] In the dissolving step S1504, an acid solution (e.g., a hydrochloric acid solution) can be used as the liquid for dissolving the liquid mixture obtained in the heating step S1503. In this case, the iron contained in the ferrous iron ore dissolves in the hydrochloric acid solution, and the tungsten contained in the ferrous iron ore remains in the solid phase. In this way, an acid solution in which iron is dissolved can be obtained simply by using an acid solution in the dissolving step S1504.

[0288] [Example Group] Examples of the present invention will be described below. In the first and second examples described above, beryl and spodumene were used as the main raw materials, respectively. In the following examples, silicon oxide, nickel sludge, ferrite, monazite, apatite, xenotime, bauxite, magnetite, iron ore, rutile, and sphalerite were used as starting materials. In the examples using spodumene as the starting material, water was used as the liquid for dissolving the mixture in the dissolving step S14. The results of each example are summarized in Table 1. Table 1 includes the results of the first and second examples.

[0289] [Table 1] In Table 1, a white circle indicates that the target element to be dissolved among the elements contained in the starting material has at least partially dissolved, and a cross indicates that the target element to be dissolved has not dissolved.

[0290] <Third Example> In the third example, the pulverizing and mixing step S12 to the dissolving step S14 of the manufacturing method M90 shown in Fig. 12 were carried out. In this example, a high-purity reagent of silicon oxide (SiO2) was used as the starting material. Also, in this example, sodium hydroxide was used as the hydroxide mixed in the pulverizing and mixing step S12.

[0291] In this example, the weight ratio of silicon oxide and sodium hydroxide mixed in the grinding and mixing step S12 was 1:10. Furthermore, in the heating step S13, dielectric heating was performed in the air atmosphere and normal pressure using a dielectric heating device 10. The heating temperature in the heating step S13 was 300°C, and the heating time was 8 minutes. By performing the heating step S13, the powder mixture melted due to the dielectric heating, and after 8 minutes, it became a milky liquid mixture. Hereinafter, when it is not necessary to distinguish between powder and liquid forms of the mixture, it will simply be referred to as the mixture. Furthermore, in this example, the liquid used to dissolve the mixture in the dissolving step S14 was either a hydrochloric acid solution or water.

[0292] When hydrochloric acid solution was used as the liquid to dissolve the mixture, silicic acid (H2SiO4) precipitated. Silicic acid is thought to be produced through two reactions from the starting material, silicon oxide. The first reaction is the reaction between silicon oxide and sodium hydroxide to produce sodium silicate (Na2SiO4). Sodium silicate is water-soluble and dissolves in the solution. However, the second reaction is the reaction between sodium silicate and hydrochloric acid to produce silicic acid. Because silicic acid is insoluble, silicic acid precipitated in the solution. The fact that the two reactions described above were occurring when hydrochloric acid solution was used as the liquid to dissolve the mixture was also confirmed by the fact that no precipitation occurred when water was used instead of hydrochloric acid. Therefore, in Table 1, the cases where silicon oxide was used as the starting material and hydrochloric acid solution was used as the liquid to dissolve the mixture are indicated by open triangles.

[0293] When water was used as the liquid for dissolving the mixture, silicon was thought to dissolve in the solution in the form of water-soluble sodium silicate. In this case, the solubility of silicon oxide was 90% or more.

[0294] As described above, in this example, silicon oxide was used as the starting material. The main component of glass materials (e.g., quartz glass) and silica stone is also silicon oxide. Therefore, the results of the third example also apply to glass materials (e.g., quartz glass) and silica stone.

[0295] <Fourth Example Group> In the fourth example group, as in the third example, the milling and mixing step S12 to the dissolving step S14 of the manufacturing method M90 shown in FIG. 12 were carried out. In this example group, an aluminum oxide (Al2O3) reagent was used as the starting material. In this example group, aluminum oxide was used as the starting material to simulate bauxite. In addition, in this example group, sodium hydroxide was used as the hydroxide mixed in the milling and mixing step S12. In addition, in this example group, the liquid for dissolving the mixture in the dissolving step S14 was tested in two cases: using a hydrochloric acid solution and using water.

[0296] After performing the dissolving step S14, a cloudy solution was obtained whether the hydrochloric acid solution or water was used as the liquid for dissolving the mixture. Analysis of these cloudy solutions revealed that aluminum oxide was soluble in both aqueous hydrochloric acid and water. The solubility of aluminum in aqueous hydrochloric acid was 99%, and the solubility of aluminum in water was 95%.

[0297] <Fifth Example Group> In the fifth example group, as in the third example, the milling and mixing step S12 to the dissolving step S14 of the manufacturing method M90 shown in Figure 12 were carried out. In this example group, a titanium oxide (TiO2) reagent was used as the starting material. In addition, in this example group, the following combinations were used for the hydroxides mixed in the milling and mixing step S12 and the liquids used to dissolve the mixture in the dissolving step S14: (1) a sodium hydroxide and hydrochloric acid solution, (2) a sodium hydroxide and sulfuric acid solution, and (3) a potassium hydroxide and sulfuric acid solution.

[0298] After performing the dissolution step S14, a cloudy solution containing residue was obtained in all of the above-mentioned cases (1), (2), and (3). Analysis of the resulting residue revealed that titanium oxide was soluble in the acid solution. The solubility of titanium in each of the combinations (1), (2), and (3) was 25%, 50%, and 98%, respectively. Note that the titanium oxide column in Table 1 shows the case of (3).

[0299] <Sixth Example Group> In the sixth example group, the milling and mixing step S12 to the dissolving step S14 of the manufacturing method M10 shown in FIG. 1 were carried out. In this example group, a beryllium oxide (BeO) reagent was used as the starting material. In this example group, beryllium oxide was used as the starting material, imitating the beryllium oxide formed on the surface of beryllium, which is an example of a neutron multiplier material. This is because beryllium is known to dissolve easily in acid solution, and because beryllium oxide is formed on the surface of beryllium that has been used as a neutron multiplier material.

[0300] In this example group, sodium hydroxide was used as the hydroxide mixed in the pulverizing and mixing step S12. In this example group, the liquid for dissolving the mixture in the dissolving step S14 was either a hydrochloric acid solution or water.

[0301] After performing the dissolving step S14, whether a hydrochloric acid solution or water was used as the liquid for dissolving the mixture, a cloudy solution containing a residue was obtained. Analysis of the resulting residue revealed that beryllium oxide was soluble in both aqueous hydrochloric acid and water. The solubility of beryllium in aqueous hydrochloric acid was 90%, and the solubility of beryllium in water was 77%.

[0302] <Seventh Example Group> In the seventh example group, the milling and mixing step S12 to the dissolving step S14 of the manufacturing method M10 shown in FIG. 1 were carried out. In this example group, lithium titanate (Li2TiO3) reagent was used as the starting material. Lithium titanate is an example of a tritium breeding material. In addition, in this example group, sodium hydroxide was used as the hydroxide mixed in the milling and mixing step S12. In addition, in this example group, the liquid for dissolving the mixture in the dissolving step S14 was used in two cases: a sulfuric acid solution and water.

[0303] After performing the dissolving step S14, whether the sulfuric acid solution or water was used as the liquid for dissolving the mixture, a cloudy solution containing a residue was obtained. Analysis of the resulting residue revealed that lithium titanate was soluble in both the aqueous sulfuric acid solution and water. The solubility of lithium in the aqueous sulfuric acid solution was 97%, and the solubility of lithium in water was 19%.

[0304] <First, second and eighth embodiments> As explained in the first example, beryl was completely dissolved in an aqueous hydrochloric acid solution (dissolution of 99% of beryllium was confirmed). Furthermore, as explained in the second example, spodumene was dissolved in an aqueous hydrochloric acid solution (dissolution of 90% or more of lithium was confirmed). Furthermore, as a modification of the first example, the liquid for dissolving the liquid mixture in the dissolving step S14 was changed from an aqueous hydrochloric acid solution to water. In this case, the solubility of beryllium in beryl was 56%.

[0305] In Example 8, spodumene was used as the starting material, and water was used as the liquid for dissolving the mixture, as in Example 2. As a result, spodumene was dissolved in water (dissolution of 96% of lithium was confirmed).

[0306] <Ninth Example> In the ninth example, as in the third example, the milling and mixing step S12 to the dissolving step S14 of the manufacturing method M90 shown in FIG. 12 were carried out. In this example, monazite ((Ce,La,Nd,Th)PO4) was used as the starting material. In this example, sodium hydroxide was used as the hydroxide mixed in the milling and mixing step S12. In this example, the heating temperature in the heating step S13 was set to 250°C. In this example, a hydrochloric acid solution was used as the liquid for dissolving the mixture in the dissolving step S14.

[0307] After performing the dissolving step S14, a yellow, cloudy solution was obtained. The results of analyzing this solution are shown in FIG. 19. FIG. 19 is a graph showing the solubilities of yttrium (Y), lanthanum (La), cerium (Ce), neodymium (Nd), samarium (Sm), terbium (Tb), and dysprosium (Dy) contained in monazite. According to FIG. 19, yttrium exhibited a solubility of approximately 80%, while lanthanum, neodymium, samarium, terbium, and dysprosium each exhibited a solubility of 50% or more and 65% or less, and cerium exhibited a solubility of approximately 20%.

[0308] <Tenth Example> In the tenth example, as in the third example, the milling and mixing step S12 to the dissolving step S14 of the manufacturing method M90 shown in FIG. 12 were carried out. In this example, apatite (Ce5(PO4)3(F,Cl,OH)1) was used as the starting material. In this example, sodium hydroxide was used as the hydroxide mixed in the milling and mixing step S12. In this example, the heating temperature in the heating step S13 was set to 250°C. In this example, a hydrochloric acid solution was used as the liquid for dissolving the mixture in the dissolving step S14.

[0309] After performing the dissolution step S14, a solution with almost no residue was obtained. Analysis of this solution revealed that the solubility of apatite was 90% or more.

[0310] <Eleventh Example> In the eleventh example, similarly to the third example, the milling and mixing step S12 to the dissolving step S14 of the manufacturing method M90 shown in FIG. 12 were carried out. In this example, xenotime (YPO4) was used as the starting material. In this example, sodium hydroxide was used as the hydroxide mixed in the milling and mixing step S12. In this example, the heating temperature in the heating step S13 was set to 250°C. In this example, a hydrochloric acid solution was used as the liquid for dissolving the mixture in the dissolving step S14.

[0311] After performing the dissolution step S14, the solubility of xenotime was about 50%.

[0312] <12th and 13th Examples> In the twelfth and thirteenth examples, similar to the third example, the milling and mixing step S12 to the dissolving step S14 of the manufacturing method M90 shown in FIG. 12 were carried out. In each of the twelfth and thirteenth examples, magnetite (Fe3O4) and iron ore (Fe2O3) were used as starting materials. In these examples, sodium hydroxide was used as the hydroxide mixed in the milling and mixing step S12. In these examples, the heating temperature in the heating step S13 was set to 250°C. In these examples, a hydrochloric acid solution was used as the liquid for dissolving the mixture in the dissolving step S14.

[0313] After performing the dissolving step S14, the obtained residue was analyzed and found to have a solubility of 90% or more for magnetite and iron ore. Furthermore, an experiment was also conducted in which magnetite was used as the starting material and water was used as the liquid for dissolving the mixture, but the magnetite did not dissolve.

[0314] <14th Example> In the 14th example, as in the third example, the milling and mixing step S12 to the dissolving step S14 of the manufacturing method M90 shown in FIG. 12 were carried out. In this example, molybdenite (MoS2) was used as the starting material. In this example, sodium hydroxide was used as the hydroxide mixed in the milling and mixing step S12. In this example, the heating temperature in the heating step S13 was set to 250°C. In this example, (1) hydrochloric acid solution, (2) 2M nitric acid solution, (3) a mixed solution of sulfuric acid and nitric acid, and (4) 5M nitric acid solution were used as liquids for dissolving the mixture in the dissolving step S14.

[0315] After performing the dissolving step S14, the obtained residue was analyzed, and the solubilities of molybdenum were 25%, 44%, 62%, and 65%, respectively, for (1) to (4). Note that the column for molybdenite in Table 1 lists the cases of (3) and (4).

[0316] <15th Example Group> In the 15th example group, as in the third example, the milling and mixing step S12 to the dissolving step S14 of the manufacturing method M90 shown in FIG. 12 were carried out. In this example group, sphalerite ((Zn,Fe)S) was used as the starting material. In addition, in this example group, sodium hydroxide was used as the hydroxide mixed in the milling and mixing step S12. In addition, in this example group, the liquid for dissolving the mixture in the dissolving step S14 was tested in two cases: using a hydrochloric acid solution and using water.

[0317] After performing the dissolving step S14, a cloudy solution containing a residue was obtained regardless of whether a hydrochloric acid solution or water was used as the liquid for dissolving the mixture. Analysis of the resulting residue revealed that sphalerite was soluble in both the hydrochloric acid solution and water. The solubility of sphalerite in the hydrochloric acid solution was 90% or more, and the solubility of sphalerite in water was 80% or more.

[0318] <16th and 17th Examples> In the 16th example, as in the third example, the milling and mixing step S12 to the dissolving step S14 of the manufacturing method M90 shown in FIG. 12 were carried out. In this example group, ferrite (FeWO4) was used as the starting raw material. In addition, in this example group, sodium hydroxide was used as the hydroxide mixed in the milling and mixing step S12. In addition, in this example group, a hydrochloric acid solution was used as the liquid for dissolving the mixture in the dissolving step S14.

[0319] In the 17th example, a separation method M150 shown in FIG. 18 was carried out. In this example, ferrite (FeWO4) was used as the starting material. In addition, in this example, sodium hydroxide was used as the hydroxide to be mixed in the pulverization and mixing step S12. In addition, in this example, water was used as the liquid for dissolving the mixture in the dissolution step S14.

[0320] In Example 16, a cloudy solution containing residue was obtained after performing dissolution step S14. Analysis of the obtained residue revealed that the solubility of iron contained in ferrous iron was 90% or more. However, in this cloudy solution, compounds containing tungsten precipitated as residue.

[0321] In the seventeenth example, after the dissolving step S1504 was performed, a cloudy solution containing residue was obtained. Analysis of the obtained residue revealed that the solubility of tungsten contained in the ferrous iron was 90% or more. However, in this cloudy solution, iron-containing compounds precipitated as residue. Next, the hydrochloric acid soaking step S1552 and the third filtration step S1553 were performed, and a clear solution was obtained. Analysis of this solution revealed that the solubility of iron contained in the ferrous iron was 90% or more.

[0322] <18th Example> In the 18th example, similarly to the third example, the milling and mixing step S12 to the dissolving step S14 of the manufacturing method M90 shown in FIG. 12 were carried out. In this example group, cobalt-rich crust was used as the starting material. In addition, in this example group, potassium hydroxide was used as the hydroxide mixed in the milling and mixing step S12. In addition, in this example group, a hydrochloric acid solution was used as the liquid for dissolving the mixture in the dissolving step S14.

[0323] In the 18th example, a solution containing a slight residue was obtained after performing the dissolving step S14. Analysis of this residue revealed that the solubility of the cobalt-rich crust was about 95%.

[0324] <19th Example Group> In the 19th example group, as in the third example, the milling and mixing step S12 to the dissolving step S14 of the manufacturing method M90 shown in FIG. 12 were carried out. In this example group, manganese nodules were used as the starting material. In addition, in this example group, sodium hydroxide and potassium hydroxide were used as the hydroxides mixed in the milling and mixing step S12. In addition, in this example group, the heating temperature in the heating step S13 was set to 250°C. In addition, in this example group, hydrochloric acid and water were used as the liquid for dissolving the mixture in the dissolving step S14. As combinations of hydroxide and liquid, (1) sodium hydroxide and hydrochloric acid solution, (2) sodium hydroxide and water, and (3) potassium hydroxide and hydrochloric acid solution were used. Note that the column for manganese nodules in Table 1 lists cases (2) and (3).

[0325] After the dissolution step S14 was carried out, a solution containing a residue was obtained in each of the above cases (1), (2), and (3). Analysis of the residue in each of cases (1), (2), and (3) revealed that the solubilities of the manganese nodules were approximately 56%, approximately 27%, and approximately 85%, respectively.

[0326] <20th Example Group> In the 20th example group, manufacturing method M140 shown in FIG. 17 was carried out. In this example group, nickel sludge was used as the starting material. In addition, in this example group, sodium hydroxide and potassium hydroxide were used as the hydroxides to be mixed in the pulverizing and mixing step S12. In addition, in this example group, water was used as the liquid for dissolving the mixture in the dissolving step S14. In addition, in the 20th example group, after carrying out manufacturing method M140, manufacturing method M140 was carried out again on the obtained solid phase.

[0327] When sodium hydroxide was used as the hydroxide, a yellowish solution containing residue was obtained after the first dissolving step S1404 was performed. Analysis of this yellowish solution revealed that the fluorine ion concentration was 16.7% and the sulfur ion concentration was 3.4%. Nickel was not detected. Analysis of the solution obtained after the second dissolving step S1404 was performed revealed that the fluorine ion concentration was 0.5% and the sulfur ion concentration was 0.3%.

[0328] When potassium hydroxide was used as the hydroxide, a yellowish solution containing residue was obtained after the first dissolution step S1404 was performed. Analysis of this yellowish solution revealed that the fluorine ion concentration was 15.8% and the sulfur ion concentration was 3.3%. Nickel was not detected. Analysis of the solution obtained after the second dissolution step S1404 was performed revealed that the fluorine ion concentration was 0.5% and the sulfur ion concentration was below the detection limit.

[0329] As described above, it was found that by carrying out manufacturing method M140, the fluorine ions and sulfur ions contained in the nickel sludge, which is the starting material, can be dissolved into solution, thereby increasing the purity of the nickel contained in the nickel sludge.

[0330] 〔summary〕 A method for producing an inorganic solution according to a first aspect of the present invention includes a heating step of dielectrically heating a powder mixture obtained by mixing an inorganic powder and a hydroxide to obtain a liquid mixture containing the inorganic powder. Note that, in this production method, the shape of the hydroxide is not limited.

[0331] The hydroxyl groups contained in the hydroxide absorb the electromagnetic waves used in dielectric heating and convert the energy of the electromagnetic waves into their own thermal energy. In the heating step of this production method, inorganic powder and hydroxide powder are mixed, so the thermal energy of the hydroxide is efficiently supplied to the inorganic material. As a result, a liquid mixture in which the inorganic material and hydroxide are melted can be obtained. This liquid mixture is easily soluble in an acid solution. Therefore, an inorganic material solution can be produced using this liquid mixture.

[0332] Furthermore, the heating step does not require high-temperature treatment (e.g., 770°C, 1650°C, or 2000°C) as in the sintering or melting treatment described in Non-Patent Document 1, and a liquid mixture can be obtained simply by subjecting the powder mixture to dielectric heating. Therefore, this production method is more energy efficient than the production method described in Non-Patent Document 1.

[0333] As described above, the present production method is a method for producing a solution of an inorganic substance, such as beryllium ore, that is difficult to dissolve in both basic and acidic solutions, and can provide a novel production method with high energy efficiency.

[0334] Furthermore, in a method for producing an inorganic solution according to a second aspect of the present invention, in addition to the configuration of the production method according to the first aspect described above, the inorganic substance contains at least one of beryllium and lithium.

[0335] Thus, an example of an inorganic substance is a substance containing at least one of beryllium and lithium.

[0336] Furthermore, in a method for producing an inorganic solution according to a third aspect of the present invention, in addition to the configuration of the method for producing an inorganic solution according to the first or second aspect described above, a configuration is adopted in which the hydroxide is at least one of sodium hydroxide and potassium hydroxide.

[0337] Thus, examples of hydroxides include sodium hydroxide and potassium hydroxide. Note that a mixture of sodium hydroxide and potassium hydroxide may also be used as the hydroxide.

[0338] Furthermore, in a method for producing an inorganic solution according to a fourth aspect of the present invention, in addition to the configuration of the method for producing an inorganic solution according to any one of the first to third aspects described above, a configuration is adopted which further includes a dissolving step of obtaining an acid solution of the inorganic substance by dissolving the liquid mixture obtained in the heating step in an acid solution or water.

[0339] According to the above-mentioned configuration, an inorganic solution can be reliably obtained.

[0340] Furthermore, in the method for producing an inorganic solution according to a fifth aspect of the present invention, in addition to the configuration of the method for producing an inorganic solution according to any one of the first to fourth aspects described above, the heating step is a step of dielectrically heating the powdered mixture under normal pressure.

[0341] In this way, in the heating step of the present production method, a liquid mixture can be obtained without dielectrically heating the powder mixture while pressurizing it. This allows for a simple production apparatus for carrying out the present production method, and reduces the effort required to obtain approval for the plant in which the production apparatus is to be installed.

[0342] An inorganic solution manufacturing apparatus according to a sixth aspect of the present invention includes a mixing section that mixes inorganic powder with hydroxide to obtain a powder mixture of inorganic substance and hydroxide, a container that contains the powder mixture, and an electromagnetic wave generating section that generates electromagnetic waves for dielectric heating.

[0343] The above configuration provides the same effects as the method for producing an inorganic solution according to the first aspect. Note that the shape of the hydroxide mixed with the inorganic powder in the mixing section of the production apparatus is not limited.

[0344] In addition, in the inorganic solution manufacturing apparatus according to the seventh aspect of the present invention, in addition to the configuration of the inorganic solution manufacturing apparatus according to the sixth aspect described above, a configuration is adopted in which the inorganic substance contains at least one of beryllium and lithium.

[0345] According to the above arrangement, the same effects as those of the method for producing an inorganic solution according to the second aspect described above can be achieved.

[0346] Furthermore, in an inorganic solution manufacturing apparatus according to an eighth aspect of the present invention, in addition to the configuration of the inorganic solution manufacturing apparatus according to the sixth or seventh aspect described above, a configuration is adopted in which the hydroxide is at least one of sodium hydroxide and potassium hydroxide.

[0347] The above arrangement provides the same effects as the method for producing an inorganic solution according to the third aspect. Note that a mixture of sodium hydroxide and potassium hydroxide may be used as the hydroxide.

[0348] Furthermore, in the apparatus for producing an inorganic solution according to a ninth aspect of the present invention, in addition to the configuration of the apparatus for producing an inorganic solution according to any one of the sixth to eighth aspects described above, a configuration is adopted in which the apparatus further comprises a waveguide interposed between the electromagnetic wave generating unit and the container for guiding the electromagnetic waves from the electromagnetic wave generating unit to the container, and an isolator provided in a mid-section of the waveguide for absorbing the electromagnetic waves propagating from the container toward the electromagnetic wave generating unit.

[0349] According to the above configuration, even if a part of the electromagnetic waves generated by the electromagnetic wave generator returns from the container toward the electromagnetic wave generator, the isolator can absorb such electromagnetic waves, thereby preventing adverse effects on the operation of the electromagnetic wave generator.

[0350] Furthermore, in the inorganic solution manufacturing apparatus according to the tenth aspect of the present invention, in addition to the configuration of the inorganic solution manufacturing apparatus according to any one of the sixth to ninth aspects described above, a configuration is adopted in which the apparatus further includes a liquid supply unit that supplies an acid solution or water to the container.

[0351] According to the above arrangement, the same effects as those of the method for producing an inorganic solution according to the fourth aspect can be achieved.

[0352] [Additional Notes] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. [Explanation of symbols]

[0353] M10 Manufacturing method (inorganic solution manufacturing method) S13 Heating process S14 Melting process 10,22 Dielectric heating device (inorganic solution manufacturing device) 11,22a Electromagnetic wave generating unit 12,22b waveguide 14,22c container 18 Isolator

Claims

1. a heating step of dielectrically heating a first mixture obtained by mixing an inorganic powder containing at least one of beryllium and lithium with a hydroxide selected from at least one of sodium hydroxide and potassium hydroxide; a dissolving step of dissolving the second mixture obtained in the heating step in a hydrochloric acid solution, a sulfuric acid solution, a nitric acid solution, or water at room temperature to obtain a solution of the inorganic substance; A method for producing an inorganic solution, comprising:

2. the heating step is a step of dielectrically heating the first mixture under normal pressure; The method for producing an inorganic solution according to claim 1 .

3. The heating temperature in the heating step is equal to or lower than the melting point of the hydroxide.

3. The method for producing an inorganic solution according to claim 1 or 2.

4. a mixing section for mixing an inorganic powder containing at least one of beryllium and lithium with a hydroxide selected from at least one of sodium hydroxide and potassium hydroxide to obtain a first mixture; a container containing the first mixture; an electromagnetic wave generating unit that generates electromagnetic waves for dielectrically heating the first mixture in the container to obtain a second mixture; a liquid supply unit for supplying a hydrochloric acid solution, a sulfuric acid solution, a nitric acid solution, or water into the container to dissolve the second mixture in the container at room temperature and obtain a solution of the inorganic substance, An apparatus for producing an inorganic solution.

5. a waveguide interposed between the electromagnetic wave generating unit and the container, which guides the electromagnetic waves from the electromagnetic wave generating unit to the container; The electromagnetic wave generating unit may further include an isolator provided in a middle section of the waveguide, the isolator absorbing electromagnetic waves propagating from the container toward the electromagnetic wave generating unit.

5. The apparatus for producing an inorganic solution according to claim 4.

6. a thermometer for measuring the temperature inside the container; a control unit that controls the output of the electromagnetic wave generating unit, the thermometer outputs a temperature signal representing the temperature of the first mixture to the control unit; the control unit controls the output of the electromagnetic wave generation unit so that the temperature of the first mixture is equal to or lower than the melting point of the hydroxide.

6. The apparatus for producing an inorganic solution according to claim 4 or 5.

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