Method for producing inorganic solutions, and apparatus for producing inorganic solutions

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] This invention relates to a manufacturing method and apparatus for producing inorganic solutions. [Background technology]

[0002] Beryllium is known to be found in Be-Si-O and Be-Si-Al-O ores. Examples of Be-Si-O ores include bertrandite and phenacite, while examples of Be-Si-Al-O ores include beryl and chrysoberyl. Hereafter, ores containing beryllium in this manner will be referred to as beryllium ore. Beryllium ore is also an example of beryllium oxide.

[0003] When producing beryllium, beryllium-containing compounds, or beryllium-containing alloys, beryllium is first extracted from beryllium ore by dissolving it in a solvent. However, dissolving beryllium ore in a solvent is not easy. Acidic solutions such as sulfuric acid are known to dissolve beryllium ore easily, but beryllium ore is not easily dissolved even in acidic solutions.

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

[0005] [Non-Patent Document 1] "Beryllium", [online], Wikipedia, [searched June 25, 2019], Internet <URL: https: / / en.wikipedia.org / wiki / Beryllium> [Overview of the Initiative] [Problems that the invention aims to solve]

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

[0007] An invention according to one aspect of the present invention has been made in view of the above-mentioned problems, and its purpose is to provide a novel manufacturing method that is highly energy-efficient for producing solutions of inorganic substances that are difficult to dissolve in either basic or acidic solutions, such as beryllium ore. [Means for solving the problem]

[0008] 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 the inorganic by dielectric heating of a powdered mixture obtained by mixing inorganic powder and hydroxide.

[0009] To solve the above problems, an apparatus for producing an inorganic solution according to a sixth aspect of the present invention comprises a mixing unit that obtains a powdered mixture of an inorganic substance and a hydroxide by mixing an inorganic powder with a hydroxide, a container for containing the powdered mixture, and an electromagnetic wave generating unit 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 poorly soluble in both basic and acidic solutions, such as beryllium ore. [Brief explanation of the drawing]

[0011] [Figure 1] This is a flowchart showing a method for producing a beryllium solution according to the first embodiment of the present invention. [Figure 2]It is a flowchart showing a method for producing beryllium, a method for producing beryllium hydroxide, and a method for producing beryllium oxide according to the second to fourth embodiments of the present invention. [Figure 3] It is a flowchart showing a method for separating titanium and lithium according to the fifth embodiment of the present invention. [Figure 4] It is a schematic diagram of a dielectric heating device according to the sixth embodiment of the present invention. [Figure 5] It is a perspective view of an isolator included in the dielectric heating device shown in FIG. 4. [Figure 6] It is a graph showing the temperature of a mixture of beryllium ore and sodium hydroxide and the output of an electromagnetic wave generation unit when a heating process is performed using the dielectric heating device shown in FIG. 4. [Figure 7] It is a graph showing the temperature of sodium hydroxide and the output of an electromagnetic wave generation unit when only sodium hydroxide is induction heated using the dielectric heating device shown in FIG. 4. [Figure 8] It is a graph showing the temperature of sodium carbonate and the output of an electromagnetic wave generation unit when only sodium carbonate is induction heated using the dielectric heating device shown in FIG. 4. [Figure 9] It is a schematic diagram of a beryllium solution production device included in a beryllium production system according to the seventh embodiment of the present invention. [Figure 10] (a) is a schematic diagram of a crystallization device, a dehydration device, and an electrolysis device included in a beryllium production system according to the seventh embodiment of the present invention. (b) is a schematic diagram of a modified example of a crystallization treatment tank included in the crystallization device shown in (a). (c)is a schematic diagram of a modified example of a dryer included in the dehydration device shown in (a). [Figure 11] (a) shows a flowchart of a method for producing lithium hydroxide according to the eighth embodiment of the present invention, and (b) shows a flowchart of a method for producing lithium carbonate according to the ninth embodiment of the present invention. < / [Figure 12] It is a flowchart showing a method for producing lithium carbonate according to the tenth embodiment of the present invention. [Figure 13]This is a flowchart showing a method for producing lithium carbonate according to the 11th embodiment of the present invention. [Figure 14] This is a flowchart showing a method for producing lithium hydroxide according to a twelfth embodiment of the present invention. [Figure 15] This is a flowchart showing a method for producing lithium carbonate according to the thirteenth embodiment of the present invention. [Figure 16] This is a flowchart showing a method for producing lithium hydroxide according to the 14th embodiment of the present invention. [Figure 17] This is a flowchart showing a method for producing a nickel compound according to the 15th embodiment of the present invention. [Figure 18] This is a flowchart showing a method for separating iron according to the 16th embodiment of the present invention. [Figure 19] This graph shows the solubility of yttrium, lanthanum, cerium, neodymium, samarium, terbium, and dysprosium in monazite, obtained in the ninth example. [Modes for carrying out the invention]

[0012] [First Embodiment] (Method for producing beryllium solution) A method for producing a beryllium solution according to the first embodiment of the present invention, M10, will be described with reference to Figure 1. Figure 1 is a flowchart of the method for producing a beryllium solution, M10. Hereinafter, the method for producing a beryllium solution, M10, will also be simply referred to as the production method, M10. In this embodiment, a method for producing a BeCl2 solution, which is an aqueous solution of beryllium chloride (BeCl2), a 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 BeCl2 solution, but may also be a BeSO4 solution, which is an aqueous solution of beryllium sulfate (BeSO4), which is the sulfate of beryllium; a Be(NO3)2 solution, which is an aqueous solution of beryllium nitrate (Be(NO3)2), which is the nitrate of beryllium; a BeF2 aqueous solution, which is an aqueous solution of beryllium fluoride (BeF2), which is the hydrofluoric acid of beryllium; a BeBr2 aqueous solution, which is an aqueous solution of beryllium bromide (BeBr2), which is the hydrobromide of beryllium; or a BeI2 aqueous solution, which is an aqueous solution of beryllium iodide (BeI2), which is the hydroiodide of beryllium.

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

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

[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, iron-manganese tungsten, PGM ore, rutile, silica, monazite, apatite, and xenotime. Lithium ore is an example of a silicate mineral containing lithium (Li). Spodumene (LiAlSi2O6) is a known example of 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). Cobalt ore contains cobalt (Co). Sulfide ore contains nickel (Ni) and antimony (Sb). Biochlore contains niobium (Nb). Molybdenum contains molybdenum (Mo). Sphalerite contains indium (In). Barite contains barium (Ba). Tantalum ore contains tantalum (Ta). Iron-manganese tungsten contains tungsten (W). PGM (Pt Group Metals) ore contains platinum (Pt) and palladium (Pd). Rutile is a crystalline form of titanium dioxide (TiO2) and is a mineral with a tetragonal crystal structure. Silica is the name of the ore when siliceous minerals and rocks 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 lanthanides. Examples of rare earth elements found 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 hydrothermal deposits, cobalt-rich crusts, and manganese nodules. 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, as well as 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. Among the muds containing one or more types of metals, rare earth mud containing rare earth elements is known.

[0018] Furthermore, in manufacturing method M10, glass may be used as a starting material. Glass, like silica, is an example of an oxide whose main component is silicon dioxide (SiO2). Such glass may also contain rare earth elements as additives. Other examples of oxides include aluminum oxide (Al2O3) and magnesium oxide (MgO). Composite oxides are also included in oxides. Composite oxides are oxides other than natural ores that contain multiple elements other than oxygen. Examples of composite oxides include yttria-stabilized zirconia (YSZ) and cordierite (2MgO·2Al2O3·5SiO2). Furthermore, in manufacturing method M10, ceramics may be used as a starting material. Examples of ceramics include alumina (Al2O3) and titania (TiO2). 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, manufacturing method M10 can be carried out to obtain solutions of, for example, hydrochloride salts of the rare metals and rare earth elements mentioned above.

[0020] Furthermore, in manufacturing method M10, metals may be used as starting materials. Examples of metals include the rare metals and rare earth elements mentioned above. The starting materials may also be alloys containing multiple metals from among these 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 materials may also be alloys containing multiple metals from among these transition metals. Such transition metal starting materials are often generated as scrap in manufacturing and processing processes for machinery and electronic components. Such scrap includes sludge, which is a type of sludge or wastewater. Sludge is also generated as waste during metal refining. The metals contained in sludge are diverse, but nickel is one example. When these metals are used as starting materials, manufacturing method M10 can be performed to obtain solutions of, for example, hydrochloride salts of each element of the rare metals, rare earth elements, and transition metals mentioned above. Therefore, these metals can be recycled. Furthermore, when nickel sludge is used as a starting material, manufacturing method M10 allows other elements (such as fluorine (F) and sulfur (S)) contained in the nickel sludge to be dissolved in the hydrochloride solution. Thus, the purity of nickel in the nickel sludge can be increased.

[0021] As described above, the starting materials used in manufacturing method M10 are diverse. When expressed using the Sturnz classification, the starting materials can be any of the following: oxides, intermetallic compounds, silicate minerals, complex oxides, phosphate minerals, oxide minerals, complex oxide minerals, sulfide minerals, tungstate minerals, and sulfate minerals.

[0022] As shown in Figure 1, the manufacturing method M10 includes an extraction step S11, a crushing and mixing step S12, a heating step S13, a dissolution step S14, a first filtration step S15, a sodium hydroxide addition step S16, a second filtration step S17, a hydrochloric acid addition step S18, a first impurity removal step S19, and a second impurity removal step S20.

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

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

[0025] Furthermore, even beryllium that has been used as a neutron multiplier remains largely beryllium (for example, about 98%). Therefore, in order to reduce the operating costs of nuclear fusion reactors, there is a strong need to establish technology for reusing beryllium, an expensive element, by dissolving it in a beryllium solution. In addition, a layer of beryllium oxide (BeO) is formed on the surface of spent beryllium. Therefore, simply immersing spent beryllium in an acidic solution will hardly dissolve the beryllium contained in the spent beryllium.

[0026] As described above, the starting material used in manufacturing method M10 is an intermetallic compound containing beryllium that functions as a neutron multiplier, comprising at least one of the following: (1) beryllium, (2) an intermetallic compound containing beryllium, (3) beryllium with an oxide layer formed on its surface, and (4) an intermetallic compound with an oxide layer formed on its surface. Furthermore, the starting material used in manufacturing method M10 may also contain lithium oxide that functions as a tritium breeder.

[0027] Furthermore, the starting materials used in manufacturing method M10 are not limited to spent neutron multipliers and tritium breeder materials from fusion reactors. These starting materials may also be beryllium and its alloys that have been spent in nuclear energy fields other than fusion and in accelerator fields, or beryllium and its alloys that are generated as industrial waste in general industrial fields. Manufacturing method M10 allows for the processing of (1) spent neutron multipliers and tritium breeder materials generated in fusion reactors, (2) beryllium and its alloys contained in spent neutron reflectors, neutron moderators, and target materials as neutron sources generated in nuclear energy fields other than fusion and in accelerator fields, and (3) beryllium and its alloys that are generated as industrial waste in general industrial fields, without distinction, and the production of new beryllium. In addition, manufacturing method M10 allows for the removal of uranium and other elements that are contained as impurities in these starting materials.

[0028] (Grinding and mixing process) The grinding and mixing step S12 is performed after the extraction step S11. In the grinding and mixing step S12, the starting material is first ground to obtain a powder of the starting material. By grinding the starting material, the particle size of the starting material is reduced, and even if an oxide layer has formed on the surface of the neutron multiplier, the oxide layer is mechanically destroyed, exposing the beryllium that was covered by the oxide layer. The technology used to grind the starting material is not limited and can be appropriately selected from existing technologies, for example, a ball mill.

[0029] Furthermore, in the grinding and mixing step S12, sodium hydroxide (NaOH) is ground to obtain sodium hydroxide powder. However, if powdered sodium hydroxide is purchased and used, the step of grinding the sodium hydroxide in the grinding and mixing step S12 may be omitted. Also, if the sodium hydroxide used in the grinding and mixing step S12 is in granular or flake form, the grinding of the sodium hydroxide in the grinding and mixing step S12 may be omitted. The shape of the sodium hydroxide used in the grinding and mixing step S12 is not limited. Note that sodium hydroxide is just one example of a hydroxide. The hydroxide used in the 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 grinding and mixing step S12, the powder of the starting material and sodium hydroxide (powdered sodium hydroxide in this embodiment) are mixed to obtain a powdered mixture of the starting material and sodium hydroxide. Hereafter, the powdered mixture of the starting material and sodium hydroxide will also be simply referred to as the powdered mixture.

[0031] (Heating process S13) The heating step S13 is a step performed after the grinding and mixing step S12 in which the powdered mixture is dielectric heated to melt the starting materials and sodium hydroxide. By performing the heating step S13, the sodium hydroxide converts the energy of the electromagnetic waves, which will be described later, into heat, and as a result, a liquid mixture containing the starting materials and sodium hydroxide is obtained. Hereinafter, the liquid mixture of the starting materials and sodium hydroxide will also be simply referred to as the liquid mixture. Since the starting materials and sodium hydroxide do not contain water, there is no need to consider the boiling of water even if the temperature of the powdered mixture or liquid mixture exceeds 100°C. Therefore, in the heating step S13, the powdered mixture can be dielectric heated under normal pressure. The liquid mixture obtained in the heating step S13 is emulsion-like, and as its temperature decreases, at least a part of it may change from emulsion-like to solid.

[0032] Dielectric heating is a general term for techniques that heat an object by applying electromagnetic waves with a predetermined frequency to it. Depending on the bandwidth of the applied electromagnetic waves, it is called high-frequency heating or microwave heating. For example, high-frequency heating involves applying electromagnetic waves in the bandwidth of 3 MHz to less than 300 MHz (so-called short waves or very high frequencies) to the object, while microwave heating involves applying electromagnetic waves in the bandwidth of 300 MHz to less than 30 GHz (so-called microwaves) to the object. Microwave ovens, which are common in homes, are an example of a device that can perform microwave heating.

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

[0034] By heating the powdered mixture using dielectric heating, the starting materials and sodium hydroxide can be transformed into a liquid mixture soluble in acidic solutions with higher energy efficiency than conventional methods. As described later, the liquid mixture dissolves readily in an acidic 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 heating step S13 can be set as appropriate. However, it is preferable that the heating temperature in heating step S13 be less than or equal to the heat resistance temperature of the container containing the powdered mixture (for example, the container 14 described in the seventh embodiment). For example, if the container is made of polytetrafluoroethylene, as in container 14, it is preferable that the heating temperature in heating step S13 be 250°C or less. An example of a heating temperature is 220°C. If the material constituting the container has corrosion resistance to acidic solutions and a heat resistance temperature above 250°C, the heating temperature in heating step S13 may be higher than 250°C. Examples of materials with a heat resistance temperature above 250°C include alumina (Al2O3) and boron nitride (BN). When a container made of alumina or boron nitride is used, the heating temperature in heating step S13 may be higher than 250°C. An example of a heating temperature when using such a container is 300°C. By increasing the heating temperature in heating step S13, it is highly likely that the time required for heating step S13 can be shortened. Furthermore, the heating time in heating step S13 can be set as appropriate. An example of a heating time is 8 minutes.

[0036] In one modified example of heating step S13, a small amount of water may be added to the powdered mixture before dielectric heating. Water can efficiently absorb the 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 temperature of the powdered mixture can be heated quickly to the desired temperature (e.g., 250°C). The amount of water added to the powdered mixture is not limited, but it is preferably 5 wt% or more based on the mass of the powdered mixture.

[0037] (melting process) The dissolution step S14 is performed after the heating step S13 and involves dissolving the liquid mixture obtained in the heating step S13 in an acid solution (in this embodiment, hydrochloric acid (HCl)) to obtain a hydrochloric acid solution of the metal contained in the starting material. 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 dissolution step S14 is not limited to hydrochloric acid, and may be at least one of sulfuric acid (H2SO4) solution, nitric acid solution, hydrofluoric acid solution, hydrobromic acid solution, and hydroiodic acid solution, or it may be a mixed acid solution obtained by mixing several of these acid solutions. An example of such a mixed acid solution is aqua regia obtained by mixing concentrated hydrochloric acid and concentrated nitric acid. In addition, water may be used as the liquid to dissolve the liquid mixture obtained in the heating step S13 in the dissolution step S14.

[0038] In the dissolution step S14, the liquid mixture dissolves even in a hydrochloric acid solution at room temperature and atmospheric pressure, but the dissolution of the liquid mixture in the hydrochloric acid solution can be accelerated by increasing the temperature of the hydrochloric acid solution. As a means of heating the hydrochloric acid solution, the device that applies electromagnetic waves used in the heating step S13 is preferred. In the dissolution step S14, it is preferable to set the temperature of the hydrochloric acid solution to less than 100 degrees Celsius in order to suppress boiling of the hydrochloric acid solution. This eliminates the need to pressurize the hydrochloric acid solution, and the dissolution step S14 can be carried out under atmospheric pressure.

[0039] (First filtration step) The first filtration step S15 is performed after the dissolution step S14. The first filtration step S15 is a step in which the solid phase and liquid phase contained in the lithium-containing beryllium solution are separated 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 performing the first filtration step S15, titanium oxide contained in the solid phase can be easily separated from beryllium chloride hydrate and lithium chloride contained in the liquid phase.

[0041] (Sodium hydroxide addition process) The sodium hydroxide addition step S16 is performed after the first filtration step S15. The sodium hydroxide addition step S16 is a step in which the polarity of the acidic solution separated by the first filtration step S15, which contains beryllium chloride hydrate and lithium chloride in the liquid phase and does not contain titanium dioxide in the solid phase, is adjusted 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. Lithium chloride, however, is dissolved in the basic solution and does not precipitate. That is, lithium chloride remains 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 performed after the sodium hydroxide addition step S16. The second filtration step S17 is a step in which the solid phase and liquid phase contained in the basic solution obtained in the sodium hydroxide addition step S16 are separated using a filter. The solid phase contains beryllium hydroxide, and the liquid phase contains lithium hydroxide.

[0044] By performing the second filtration step S17, the beryllium hydroxide contained in the solid phase and the lithium hydroxide contained in the liquid phase can be easily separated.

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

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

[0047] (First impurity removal process) The first impurity removal step S19 is performed after the hydrochloric acid addition step S18. The first impurity removal step S19 is a step in which the first element is removed 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 usable in the first impurity removal step S19 include tri-n-octylphosphine oxide (TOPO), di-(2-ethylhexyl) phosphoric acid (D2EHPA), tri-n-butyl phosphate (TBP), and ethylenediaminetetraacetic acid (EDTA). Another example of a commercially available organic compound usable 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+ It can adsorb V, Zr, rare earth elements, and actinide elements. D2EHPA can adsorb U, Co, Ni, Mn, etc. TBP can adsorb U, Th, etc. EDTA-type resins 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 elements.

[0050] These organic compounds dissolve in organic solvents (such as kerosene, cyclohexane, and benzene). After carrying out the hydrochloric acid addition step S18, the HCl solution containing these organic compounds (hereinafter also referred to as the organic compound solution) is mixed with the HCl solution and stirred, causing the organic compounds to adsorb the first element.

[0051] In the first impurity removal step S19, the HCl solution used to mix the organic compound solution is preferably acidic, and more preferably has a pH of 2 or less. This configuration allows the organic compound to adsorb the first element without adsorbing beryllium, thereby increasing the efficiency of the organic compound's adsorption of the first element. The closer the HCl solution is to neutral, the higher the efficiency of the organic compound's adsorption of beryllium becomes, while the efficiency of its adsorption of the first element decreases.

[0052] In this embodiment, TOPO and kerosene are used as the organic compound and organic solvent 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 beryllium solution, which is an aqueous solution, and the organic compound solution, obtained in the hydrochloric acid addition step S18, separate into two layers when left to stand for a while. Therefore, the beryllium solution, in which the content of the first element has been suppressed by carrying out the first impurity removal step S19, and the organic compound solution containing the first element can be easily separated.

[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 producing a beryllium solution by dissolving the starting material in an acidic solution, even if the starting material contains the first element, which is an element other than beryllium as described above, the concentration of the first element contained when producing beryllium, beryllium hydroxide, or beryllium oxide from the beryllium solution can be reduced. Examples of the first element include uranium, thorium, plutonium, and americium.

[0055] As a specific example, when beryllium is produced using beryllium chloride produced by manufacturing method M10, which includes the first impurity removal step S19, the concentration of uranium contained in the beryllium can be suppressed to less than 0.7 ppm. Beryllium with a uranium concentration of less than 0.7 ppm will have a uranium concentration below the threshold that determines whether or not it can be disposed of in shallow land, even when used as a neutron multiplier in a nuclear fusion reactor. Therefore, beryllium included in one aspect of the present invention can be disposed of in shallow land as is, even when used as a neutron multiplier in a nuclear fusion reactor.

[0056] (Second impurity removal process) The second impurity removal step S20 is performed after the first impurity removal step S19, and is a step in which the second element is removed from the beryllium solution by adjusting the polarity of the beryllium solution obtained in the hydrochloric acid addition step S18 from acidic to basic, via neutral. 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 it is saturated. As a result, after the beryllium solution becomes neutral (pH 7), elements other than beryllium (e.g., Al and Fe) precipitate in the beryllium solution as hydroxides (e.g., Al(OH)3 and Fe(OH)3). Even when the solution is saturated with sodium bicarbonate, 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] By performing the second impurity removal step S20, hydroxides of elements other than beryllium that have precipitated in the beryllium solution can be easily removed from the beryllium solution by filtering the beryllium solution.

[0059] Furthermore, it is preferable to add HCl again to the beryllium solution from which the second element has been removed by performing the second impurity removal step S20. By adding HCl again to the beryllium solution in this way, the polarity of the Be(OH)2 solution is adjusted to acidic via neutral, and high-purity 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 producing a beryllium solution by dissolving the 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 producing beryllium, beryllium hydroxide, or beryllium oxide using the beryllium solution can be reduced.

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

[0062] Furthermore, if the manufacturing method M10 includes a preheating step, it is preferable that the preheating step, similar to the heating step S13, involves dielectric heating of the basic solution containing beryllium oxide by applying microwaves.

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

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

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

[0066] (Variation of the method for producing beryllium solution) As described above, in this embodiment, manufacturing method M10 was explained using used tritium breeding material and neutron multiplier as starting materials. In this modified example, manufacturing method M10 when beryl is used as a starting material will be briefly explained. Beryl is a form of beryllium ore of the Be-Si-Al-O system 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 materials may also include ores other than beryl (for example, stearate, which will be described later).

[0067] In this modified example, since beryl extracted from a mine is used as the starting material, the extraction process S11 can be omitted.

[0068] In the grinding and mixing step S12, beryl powder is obtained by grinding beryl. Similarly, sodium hydroxide powder is obtained by grinding sodium hydroxide. Then, a powdered mixture of beryl and sodium hydroxide is obtained by mixing the respective powders of beryl and sodium hydroxide. In this modified example, the form of sodium hydroxide is not limited to powder.

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

[0070] The melting point of beryl is 1410°C, and the melting point of sodium hydroxide is 318°C. Therefore, the heating temperature in heating step S13 is lower than these melting points. Despite this, the beryl and sodium hydroxide melt, which is thought to be due to the melting-promoting effect of the applied electromagnetic waves. In manufacturing method M10, since powdered beryl and sodium hydroxide are mixed, the applied electromagnetic waves directly act on the inside of the powdered mixture, allowing for direct heating of the interior. Furthermore, it is expected that a discharge occurs inside the powdered mixture with the application of electromagnetic waves, and this discharge is also thought to promote melting. As a result, in manufacturing method M10, beryl can be transformed into a state where it can be dissolved in hydrochloric acid solution despite the low temperature of 220°C. In the technology described in Non-Patent Literature 1, for example, beryl is melted at a high temperature of about 2000°C. Compared to this technology, manufacturing method M10 can reduce energy consumption to approximately 1 / 10000 (0.01%).

[0071] Even after the heating step S13 and the dissolution step S14 have been performed, the silicon containing beryl remains in the hydrochloric acid solution as a solid oxide. Therefore, by performing the first filtration step S15, silicon can be removed from the beryllium chloride solution.

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

[0073] The first impurity removal step S19 and the second impurity removal step S20 are preferably carried out even when beryl is used as the starting material. By carrying out the first impurity removal step S19, the concentration of the first element (e.g., uranium, thorium, plutonium, americium, etc.) contained in the beryllium chloride solution can be reduced. Furthermore, by carrying out the second impurity removal step S20, the concentration of the second element (e.g., aluminum, iron, etc.) contained in the beryllium chloride solution can be reduced. Beryl contains aluminum, but by carrying out 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 for manufacturing lithium solution) In the modified method for producing beryllium solution described above, beryl is used as the starting material, and a hydrochloric acid solution in which beryllium chloride hydrate (BeCl2·xH2O) is dissolved is obtained. Next, we will briefly explain the case in which lithium ore is used as the starting material, and a hydrochloric acid solution in which lithium chloride (LiCl), the hydrochloride salt of lithium, is dissolved is obtained. This manufacturing method is a modified version of the beryllium solution production method described above, in which the starting material is changed from beryl to lithium ore, and can therefore be considered a modified version of the beryllium solution production method.

[0076] This manufacturing method describes a method for producing a LiCl solution, which is an aqueous solution of lithium chloride (LiCl), a lithium hydrochloride salt. LiCl solution is an example of an inorganic solution. However, the lithium solution produced using this manufacturing method is not limited to LiCl solution, and may also be a Li2SO4 solution, which is an aqueous solution of lithium sulfate (Li2SO4), a lithium sulfate salt; a LiNO3 solution, which is an aqueous solution of lithium nitrate (LiNO3), a lithium nitrate salt; lithium fluoride (LiF), a lithium hydrofluoride salt; lithium bromide (LiBr), a lithium hydrobromide salt; or lithium iodide (LiI), a lithium hydroiodide salt.

[0077] Lithium ore is a general term for ores containing lithium, and is also an example of lithium oxide. Lithium ore is crystalline. Examples of lithium ore include spodumene (LiAlSi2O6) and lepidolite (K(Al,Li)2(Si,Al)4O6). 10 (OH,F)2), Petalite (LiAlSi4O 10 ), and lithium tourmaline (Elbaite,Na(Li,Al)3Al6(BO3)3Si6O 18 (OH)4) is one example. In this manufacturing method, stearate, a form of lithium ore, is used as an example of a starting material. In conventional technology, stearate is subjected to calcination at a temperature of 1000°C or higher in order to dissolve it in a solution.

[0078] In the crushing and mixing step S12, stearate powder is obtained by crushing stearate. Similarly, sodium hydroxide powder is obtained by crushing sodium hydroxide. Then, a powdered mixture of stearate and sodium hydroxide is obtained by mixing the respective powders of stearate and sodium hydroxide. In this modified example, the form of sodium hydroxide is not limited to powder.

[0079] The heating step S13 and the dissolution step S14 are as described above with reference to Figure 1.

[0080] Even after the heating step S13 and the dissolution step S14 have been performed, the silicon containing stearate remains in the hydrochloric acid solution as a solid oxide. Therefore, silicon can be removed from the lithium solution by performing the first filtration step S15.

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

[0082] The first impurity removal step S19 and the second impurity removal step S20 are also preferable when stearate is used as the starting material. By performing the first impurity removal step S19, the concentration of the 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 the second element (e.g., aluminum, iron, etc.) contained in the lithium solution can be reduced. Although stearate contains aluminum, the second impurity removal step S20 can be used to reliably remove aluminum from the lithium solution.

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

[0084] (Beryllium manufacturing method M20) As shown in Figure 2, manufacturing method M20 includes the extraction step S11, crushing and mixing step S12, heating step S13, dissolution step S14, first filtration step S15, sodium hydroxide addition step S16, second filtration step S17, first impurity removal step S19, and second impurity removal step S20, which are included in manufacturing method M10 shown in Figure 1, as well as an anhydrous step S21 and an electrolysis step S22. Hereafter, the extraction step S11, heating step S13, first filtration step S15, sodium hydroxide addition step S16, second filtration step S17, first impurity removal step S19, and second impurity removal step S20 will also be simply referred to as each step S11 to S20.

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

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

[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 to as close to zero as possible. In other words, the beryllium chloride hydrate can be dehydrated.

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

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

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

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

[0092] As described above, by implementing manufacturing method M20, metallic beryllium can be produced from starting materials.

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

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

[0095] As described above, Be(OH)2 can be produced from starting materials by implementing manufacturing method M30.

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

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

[0098] As described above, BeO can be produced from starting materials by implementing manufacturing method M40.

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

[0100] [Fifth Embodiment] (Method for separating titanium and lithium M50) A fifth embodiment of the present invention, a method for separating titanium and lithium M50, will be described with reference to Figure 3. Figure 3 is a flowchart of the titanium and lithium separation method M50. Hereinafter, the titanium and lithium separation method M50 will also be simply referred to as separation method M50.

[0101] As shown in Figure 3, separation method M50 includes the extraction step S11, grinding and mixing step S12, heating step S13, dissolution step S14, and first filtration step S15, which are included in manufacturing method M10 shown in Figure 1, as well as the grinding step S51, hydrochloric acid immersion step S52, and third filtration step S53. Hereafter, the extraction step S11, grinding and mixing step S12, heating step S13, dissolution step S14, and first filtration step S15 will also be simply referred to as each step S11 to S15.

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

[0103] The grinding step S51 is a step in which the lithium titanate contained in the solid phase after the first filtration step S15 is ground to reduce the particle size of the lithium titanate. The technology used to grind the lithium titanate is not limited and can be appropriately selected from existing technologies, for example, a ball mill.

[0104] If lithium titanate can be pulverized more finely, the ratio of surface area to the total volume of 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 during the hydrochloric acid immersion step S52 described later. 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 lithium titanate obtained after the pulverization step S51 by considering the time required for the hydrochloric acid immersion step S52, the time required for the pulverization step S51, and the cost required for the pulverization step S51.

[0105] Furthermore, the particle size of lithium titanate can be determined using any of the mean diameter, mode diameter, or median diameter. When measuring the particle size distribution of lithium titanate, the mean diameter is the particle size that represents the average value of the obtained particle size distribution, the mode diameter is the particle size with the highest frequency in the particle size distribution, and the median diameter is the particle size at which the cumulative frequency in the particle size distribution reaches 50%.

[0106] In this embodiment, grinding step S51 is performed so that the average diameter of lithium titanate is 100 μm.

[0107] The hydrochloric acid immersion step S52 is performed after the grinding step S51. The hydrochloric acid immersion step S52 is a step in which the lithium titanate, which has been ground in the grinding step S51, is immersed in a hydrochloric acid solution. By performing 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 the hydrochloric acid immersion step S52 contains titanium oxide contained in the solid phase and lithium chloride contained in the liquid phase.

[0108] Furthermore, if it is desired to dissolve the lithium contained in lithium titanate in the hydrochloric acid solution more quickly, the same method as in heating step S13 may be applied, and the hydrochloric acid solution containing lithium titanate may be subjected to dielectric heating.

[0109] The third filtration step S53 is performed after the hydrochloric acid immersion step S52. The third filtration step S53 is a step in which titanium oxide contained in the solid phase and lithium chloride contained in the liquid phase are separated using a filter.

[0110] By performing the third filtration step S53, titanium oxide contained in the solid phase and lithium chloride contained in the liquid phase can be easily separated.

[0111] Furthermore, it is preferable to return the acidic solution containing lithium chloride separated in the third filtration step S53 to the sodium hydroxide addition 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 addition step S16, the lithium compound can be recovered more efficiently. In other words, the grinding step S51, the hydrochloric acid immersion step S52, and the third filtration step S53 of separation method M50 can be included as part of manufacturing method M10.

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

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

[0114] As described in the first embodiment, dielectric heating is classified into either high-frequency heating or microwave heating depending on the bandwidth of the electromagnetic wave applied. The dielectric heating apparatus 10 is an apparatus that performs microwave heating, one of high-frequency heating and microwave heating, on an object.

[0115] <Configuration of a dielectric heating device> As shown in Figure 4, the dielectric heating device 10 comprises an electromagnetic wave generating unit 11, a waveguide 12, an electromagnetic wave application unit 13, a container 14, a rotary table 15, a stirrer 16, and a thermometer 17, and further comprises an isolator 18 as shown in Figure 5. The dielectric heating device 10 also further comprises a control unit, which is not shown in Figure 4.

[0116] (Electromagnetic wave generating section) The electromagnetic wave generator 11 is configured to oscillate electromagnetic waves having a predetermined frequency. The predetermined frequency can be appropriately selected, for example, within the microwave band, 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 household microwave ovens.

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

[0118] (Isolator) As shown in Figure 5, an isolator 18 is provided in the middle section of the waveguide 12. The isolator 18 comprises a circulator 181, a dummy load 182, and a cooling tube 183. The circulator 181 is inserted into the middle section of the waveguide 12.

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

[0120] The magnetic field formed by the magnet and the electromagnetic waves passing through the circulator 181 interact, causing electromagnetic waves incident on port P1 to be emitted from port P2, and electromagnetic waves incident on port P2 to be emitted from port P3. Therefore, the circulator 181 couples the electromagnetic waves generated by the electromagnetic wave generation unit 11 toward the electromagnetic wave application unit 13, and couples the electromagnetic waves reflected in the internal space of the electromagnetic wave application unit 13 toward the 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 section 13 and converts that energy into heat.

[0122] The dummy load 182 is provided with a cooling tube 183. The cooling tube 183 is configured to circulate cooled refrigerant (e.g., water or air). The cooled refrigerant can remove heat from the dummy load 182, thus preventing the temperature of the dummy load 182 from rising excessively.

[0123] The circulator 181 configured as described above can couple the electromagnetic waves generated by the electromagnetic wave generation unit 11 to the electromagnetic wave application unit 13 with almost no loss, and can also absorb the electromagnetic waves reflected in the internal space of the electromagnetic wave application unit 13. In other words, the circulator 181 can propagate electromagnetic waves from the electromagnetic wave generation unit 11 to the container 14 with almost no loss, and can also absorb the electromagnetic waves propagating from the container 14 to the electromagnetic wave generation unit 11. Therefore, it is possible to suppress the return of electromagnetic waves reflected in the internal space of the electromagnetic wave application unit 13 to the electromagnetic wave generation unit 11, thereby preventing adverse effects on the operation of the electromagnetic wave generation unit 11.

[0124] (Electromagnetic wave application section) The electromagnetic wave application unit 13 is a metal box-shaped member with a hollow internal space, and is configured to accommodate the container 14 within its internal space. The electromagnetic wave application unit 13 applies electromagnetic waves irradiated from the other end of the waveguide 12 to the container 14 and the object to be heated contained within the container 14. The electromagnetic wave application unit 13 is configured to confine the electromagnetic waves within its internal space, making it difficult for them to leak to the outside.

[0125] (container) Container 14 is a dish-shaped container. The shape of container 14 is a powdered mixture M of the starting material and sodium hydroxide. P The shape is not limited as long as it can accommodate the powdered mixture M. However, the thermometer 17 described later is used to measure the powdered mixture M. P To measure the temperature, it is preferable that the container 14 has a large opening. Also, if the dissolution step S14 is carried out using the same container 14 after the heating step S13, it is preferable that the container 14 has a volume capable of holding a predetermined amount of hydrochloric acid solution.

[0126] Incidentally, when obtaining a powdery mixture by mixing the powder of the starting material and sodium hydroxide (in the examples described later, the powder of sodium hydroxide) using a mortar as in the examples described later, the mortar functions as a mixing part. Further, when obtaining a powdery mixture by putting the powder of the starting material and the powder of sodium hydroxide in the 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 having a high transmittance with respect to the electromagnetic wave oscillated by the electromagnetic wave generation part 11 (2.45 GHz in this embodiment). Further, the container 14 is preferably made of a material having high resistance to acids and bases. When the container 14 is made of a material having high resistance to acids and bases, after performing the heating step S13, the dissolution step S14 can be performed by pouring a hydrochloric acid solution into the container 14.

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

[0129] (Rotating table) The rotating table 15 is a sample stage provided on the bottom surface of the internal space of the electromagnetic wave application part 13, and is configured such that the container 14 can be placed on the upper surface. The rotating table 15 is circular in plan view, and is configured to rotate at a predetermined speed with its central axis as the rotation axis. According to this configuration, since the container 14 placed on the upper surface of the rotating table 15 rotates periodically, the powdery mixture M P can be heated more uniformly.

[0130] (Stirrer) The stirrer 16 is a metal, wing-shaped member provided on the ceiling surface of the internal space of the electromagnetic wave application unit 13. It is fixed to the ceiling surface in a rotatable state by a support rod connected to the center of the wing-shaped member. By rotating at a predetermined speed with the support rod as the axis of rotation, the stirrer 16 reflects the electromagnetic waves emitted by the electromagnetic wave generation unit 11 and scatters them in the internal space of the electromagnetic wave application unit 13. With this configuration, because the stirrer 16 scatters the electromagnetic waves, the powdered mixture M P This allows for more uniform heating.

[0131] (thermometer) Thermometer 17 detects powdered mixture M P This is a radiation thermometer that measures the temperature of container 14 by detecting the infrared radiation emitted by the thermometer 17. The thermometer 17 has a light-receiving part which is a powdered mixture M P It is fixed to a part of the side wall of the electromagnetic wave application unit 13 so that infrared radiation from it can be detected. The thermometer 17 measures the powdered mixture M P A temperature signal representing the temperature is output to the control unit.

[0132] (Control Unit) The control unit may control the output of the electromagnetic wave generator 11 so that the output reaches a predetermined value, or it may control the output of the electromagnetic wave generator 11 so that the temperature of the temperature signal received from the thermometer 17 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 11 so that the output value changes over time. An example of an output control pattern is to maintain an output of 300W for 600 seconds and then set the output to 0W.

[0133] Taking manufacturing method M10 as an example, a dielectric heating device 10 configured in this way is used to heat the powdered mixture M in the internal space of the container 14. PBy containing the mixture, the heating step S13 can be carried out. Furthermore, the dissolution step S14 can be carried out by pouring the hydrochloric acid solution into the container 14 after the heating step S13 has been carried out. In addition, when the dissolution step S14 is carried out using the dielectric heating device 10, the hydrochloric acid solution can be heated, which can promote the 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 embodiment of the manufacturing method M10 using the dielectric heating device 10 described above will be explained with reference to Figure 6. Figure 6 is a graph showing the temperature change of mixture M in an example of the heating step S13 described above. In this embodiment, beryl was used as the starting material.

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

[0136] In this embodiment, in heating step S13, the powdered mixture M P The powdered mixture M was placed on a container 14 made of aluminum oxide (alumina: Al2O3) and subjected to dielectric heating in a dielectric heating device 10 under atmospheric pressure and air. The output of the dielectric heating device 10 was set to 300W and the heating time was set to 8 minutes. By performing the heating step S13, the powdered mixture M P The mixture melted upon dielectric heating, and after 8 minutes, it became a completely emulsion-like liquid mixture. Hereafter, when it is not necessary to distinguish whether the mixture is in powder or liquid form, it will simply be referred to as mixture M. In the heating step S13 of this embodiment, the maximum temperature reached by mixture M was approximately 220°C.

[0137] Furthermore, after setting the output value to 300W, the temperature of mixture M remained at 50°C for the period from 0 seconds to approximately 345 seconds. This is because the lower limit of the detectable temperature of thermometer 17 is 50°C.

[0138] In this example, after cooling the liquid mixture to room temperature, in the dissolution step S14, an aqueous hydrochloric acid solution (HCl: 6 mol / L, 20 cm³) was added. 3 The liquid mixture was added to the solution under atmospheric conditions, room temperature, and normal pressure. As a result, the liquid mixture completely dissolved in the hydrochloric acid solution (99% beryllium dissolution was confirmed).

[0139] [Second Example] A second embodiment of the manufacturing method M10 using the dielectric heating device 10 described above will be explained below. In this embodiment, spodumene (LiAlSi2O6), an example of lithium ore, was used as the starting material.

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

[0141] In this embodiment, in heating step S13, the powdered mixture M P The mixture was placed on a container 14 made of aluminum oxide (alumina: Al2O3) and subjected to dielectric heating in a dielectric heating device 10 under atmospheric pressure and air. The temperature history due to dielectric heating showed a similar trend to that shown in Figure 6. The output of the dielectric heating device 10 was set to 300W and the heating time was set to 8 minutes. By performing the heating process S13, the powdered mixture M was heated. PThe mixture melted upon dielectric heating, and after 8 minutes, it became a completely emulsion-like liquid mixture. Hereafter, when it is not necessary to distinguish whether the mixture is in powder or liquid form, it will simply be referred to as mixture M. In the heating step S13 of this embodiment, the maximum temperature reached by mixture M was approximately 220°C.

[0142] In this example, after cooling the liquid mixture to room temperature, in the dissolution step S14, an aqueous hydrochloric acid solution (HCl: 6 mol / L, 20 cm³) was added. 3 The liquid mixture was added to the solution under atmospheric conditions, room temperature, and normal pressure. As a result, the liquid mixture dissolved in the hydrochloric acid solution (over 90% lithium dissolution was confirmed).

[0143] (Reference example) Furthermore, as a reference example of the heating step S13 included in the manufacturing method M10, dielectric heating was performed on sodium hydroxide powder and sodium bicarbonate powder. The results will be explained with reference to Figures 7 and 8. Figure 7 is a graph showing the temperature change of sodium hydroxide obtained as a result of dielectric heating of sodium hydroxide powder. Figure 8 is a graph showing the temperature change of sodium bicarbonate obtained as a result of dielectric heating of sodium bicarbonate powder.

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

[0145] Referring to Figure 7, it was found that the sodium hydroxide powder was heated by dielectric heating, reaching a maximum temperature of approximately 250°C. After this dielectric heating, the sodium hydroxide was molten and in liquid form. From these results, it can be seen that in the heating step S13 of manufacturing method M10, the powdered 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, as can be seen in Figure 8, the temperature of sodium carbonate powder hardly rises even when dielectric heating is performed. In Figure 8, the temperature of sodium carbonate is below 50°C, which is the lower limit of the detection range of thermometer 17. From this result, it can be concluded that sodium carbonate, which is used in the conventional alkali fusion method, absorbs almost no energy from the electromagnetic waves used for dielectric heating.

[0147] Although the graph is omitted, it was found that when dielectric heating was performed on at least one of the beryl and spodumine powders alone, the temperature of at least one of the beryl and spodumine powders hardly rose, similar to the case of sodium carbonate powder. From this result, it can be concluded that beryl and spodumine, which are not mixed with sodium hydroxide, absorb almost no energy from the electromagnetic waves used for dielectric heating.

[0148] [Seventh Embodiment] <Beryllium manufacturing system> A beryllium production system 20 according to the seventh embodiment of the present invention will be described with reference to Figures 9 and 10. Figure 9 is a schematic diagram of a beryllium solution (BeCl2 solution) production apparatus 20A, which constitutes a part of the beryllium production system 20. Figure 10(a) is a schematic diagram of a crystallization apparatus 20B, an anhydrous apparatus 20C, and an electrolytic apparatus 20D. Figure 10(b) is a schematic diagram of a modified crystallization treatment tank 31 provided in the crystallization apparatus 20B shown in Figure 10(a). Figure 10(c) is a schematic diagram of a modified dryer 33 provided in the anhydrous apparatus 20C shown in Figure 10(a). The crystallization apparatus 20B, the anhydrous apparatus 20C, and the electrolytic apparatus 20D each constitute a part of the beryllium production system 20. 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] As shown in Figures 9 and 10, the manufacturing system 20 comprises a manufacturing apparatus 20A, a crystallization apparatus 20B, an anhydrous apparatus 20C, and an electrolytic apparatus 20D, and is an apparatus for carrying out the manufacturing method M20 shown in Figure 2(a). More specifically, the manufacturing apparatus 20A is an apparatus for carrying out each step of the manufacturing method M10 shown in Figure 1, excluding the extraction step S11; the crystallization apparatus 20B and the anhydrous apparatus 20C are apparatus for carrying out the anhydrous step S21 shown in Figure 2(a); and the electrolytic apparatus 20D is an apparatus for carrying out the electrolysis step S22 shown in Figure 2(a).

[0150] In this embodiment, as in the first embodiment, lithium titanate (Li2TiO3), an example of a tritium breeding material, and beryllium (Be), an example of a neutron multiplier, which has an oxide layer made 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 has an oxide layer made of beryllium oxide (BeO) formed on its surface, as exemplified in the first embodiment.

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

[0152] The pulverizer 21a grinds the input starting materials, lithium titanate and beryllium with an oxide layer formed on its surface, into powder. Then, the pulverizer 21a supplies the lithium titanate and beryllium powder to the feeder F1a. The pulverizer 21a can be appropriately selected from existing pulverizers according to the desired specifications. Therefore, a detailed explanation of the pulverizer 21a is omitted here. By grinding the starting materials using the pulverizer 21a, even if an oxide layer is formed on the surface of beryllium, which is an example of a neutron multiplier, the oxide layer can be mechanically destroyed, exposing the beryllium that was covered by the oxide layer. Therefore, the rate at which it melts together with beryllium 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 the 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 grinds the introduced sodium hydroxide into a powder. Then, the pulverizer 21b 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 explanation of the pulverizer 21b is omitted here. By grinding the sodium hydroxide using the pulverizer 21b, the particle size of the sodium hydroxide can be made to the desired size. As mentioned above, the form of sodium hydroxide is not limited to powder. Therefore, the pulverizer 21b can be omitted in the manufacturing apparatus 20A.

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

[0156] The dielectric heating device 22 comprises an electromagnetic wave generating unit 22a, a waveguide 22b, a container 22c, a stirring mechanism, and a thermometer. The dielectric heating device 22 performs the heating step S13 and the melting step S14 of the manufacturing method M10 shown in Figure 1.

[0157] The electromagnetic wave generation unit 22a is controlled by the control unit and is configured to generate electromagnetic waves having a predetermined frequency. The predetermined frequency can be appropriately selected, for example, within the microwave band, 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 household microwave ovens.

[0158] Waveguide 22b is a cylindrical metal member, with one end connected to the electromagnetic wave generator 22a and the other end connected to the container 22c. Waveguide 22b guides the electromagnetic waves emitted by the electromagnetic wave generator 22a from one end to the other, and radiates these electromagnetic waves from the other end into the internal space of the container 22c. Although not shown in Figure 9, an isolator, as shown in Figure 5, is provided in the middle section of waveguide 22b. In this case, waveguide 12 shown in Figure 5 can be replaced with waveguide 22b.

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

[0160] A thermometer, not shown in Figure 9, detects the temperature of the contents (a powdered 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 type thermometer such as a radiation thermometer, or a contact type thermometer such as a thermocouple. In either case, it is preferable that the thermometer is installed in the internal space of container 22c and configured to directly detect the temperature of the contents contained in that 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 it may control the output of the electromagnetic wave generator 22a so that the temperature represented 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 represented by the temperature signal changes over time according to a predetermined profile. An example of a predetermined temperature profile is a pattern in which the temperature is changed from room temperature to 250°C over 5 minutes, and then maintained at 250°C for 10 minutes.

[0162] The dielectric heating apparatus 22 configured in this way obtains a liquid mixture containing the starting material and sodium hydroxide by performing the heating step S13 of the manufacturing method M10 shown in Figure 1.

[0163] Next, the HCl solution is supplied via valve V1. The dissolution process S14 is carried out by supplying the HCl solution to container 22c via valve V1. This 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 become a beryllium solution (BeCl2 solution) containing lithium. As mentioned above, the liquid used to dissolve the liquid mixture containing the starting material and sodium hydroxide is not limited to an acidic solution such as the HCl solution, but may also be water. When water is used as this liquid, the dissolution process S14 is carried out by supplying water to container 22c via valve V1.

[0164] Furthermore, while the dissolution process S14 is being carried out, the control unit may control the output of the electromagnetic wave generator 22a so that the output reaches a predetermined value, or it 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 while the dissolution process S14 is being carried out, the dissolution of the liquid mixture into the HCl solution is promoted. In addition, while the dissolution process S14 is being carried out, the control unit may continue to operate the stirring mechanism.

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

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

[0167] Valve V3 opens and closes the path between filter 23 and container 24, which will be described later. The control unit keeps valve V3 open at least while a 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 internal space and acid- and base-resistant properties. Regarding the container configuration, each of the containers 26, 27, 28, and 30, described later, is an acid-resistant box-shaped member. NaOH solution is supplied to container 24 via valve V4. This mechanism for supplying the NaOH solution to the beryllium solution in container 24 via valve V4 functions as an NaOH solution supply unit that supplies the NaOH solution to the beryllium solution.

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

[0170] Although not shown in Figure 9, a stirring mechanism for stirring the BeCl2 solution containing LiCl and the NaOH solution may be provided inside container 24. Similarly, stirring mechanisms may be provided inside containers 26, 27, 28, and 30, which will be described later.

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

[0172] The centrifuge 25 separates the liquid phase (i.e., the NaOH solution containing LiOH) from the solid phase (i.e., Be(OH)2) of the NaOH solution containing Be(OH)2 and LiOH. In other words, 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 explanation of the centrifuge 25 is omitted here. The Be(OH)2 obtained in the second filtration step S17 is introduced into the internal space of the container 26, which will be described later, and the NaOH aqueous solution containing LiOH obtained in the second filtration step S17 is recovered in a recovery line (not shown).

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

[0174] Container 26 is supplied with HCl solution via valve V6. The Be(OH)2 and HCl solution supplied to container 26 are mixed in the internal space of container 26. That is, the hydrochloric acid addition step S18 of manufacturing method M10 is carried out in the internal space of container 26. As a result, a beryllium solution (BeCl2 solution) is formed inside container 26 in which the generated 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 keeps valve V7 closed while the hydrochloric acid addition step S18 is being performed, and opens valve V7 after the hydrochloric acid addition step S18 is completed. As a result, the beryllium solution obtained in the hydrochloric acid addition step S18 is supplied from container 26 to container 27.

[0176] The container 27 is supplied with an organic compound solution via valve V8. This mechanism for supplying the organic compound solution to the container 27 via 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 is omitted here.

[0177] The beryllium solution and the organic compound solution supplied to container 27 are mixed in the internal space of container 27. That is, the first impurity removal step S19 is performed in the internal space of container 27. As a result, the beryllium solution with a suppressed content of the first element and the organic compound solution containing the first element separate into two layers inside container 27. Since the specific gravity of the beryllium solution is higher than that 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 completed, 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. Subsequently, 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 into the recovery line.

[0180] Container 28 is supplied with baking soda via valve V11. This valve V11, which supplies baking soda to container 28, functions as a baking soda supply unit that supplies baking soda to the beryllium chloride solution. This baking soda is the same baking soda described in the second impurity removal step S20 of manufacturing method M10. Therefore, a further explanation of the baking soda is omitted here.

[0181] The beryllium solution and baking soda supplied to container 28 are mixed in the internal space of container 28. That is, the second impurity removal step S20 is carried out in the internal space of container 28. As a result, hydroxides of the second element precipitate inside 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 the path between the internal space of container 28 and the filter described later. The control unit keeps valve V12 closed 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 by 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 allow the liquid phase (i.e., the beryllium hydroxide solution) of a beryllium hydroxide solution containing the hydroxide of the second element to pass through, and to filter out 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 explanation of filter 29 is 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 while a beryllium hydroxide solution containing the hydroxide of the second element is being supplied to filter 29. As a result, the beryllium hydroxide solution obtained by the second impurity removal step S20, in which the content of the second element is suppressed, is supplied from filter 29 to container 30.

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

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

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

[0188] The crystallization treatment tank 31 comprises an inner tank and an outer tank. Hot water is supplied to the internal space of the outer tank via valve V16. The internal space of the inner tank is supplied with beryllium solution (BeCl2 solution) produced by the manufacturing apparatus 20A. The aforementioned hot water heats the beryllium solution and HCl solution contained in the inner tank. The use of hot water is an example of a heating means employing an external heating method.

[0189] Chiller C, the condensate tank, and pump P constitute a vacuum dehydration system. Pump P exhausts the internal space of the inner tank. 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 the cooling of chiller C.

[0190] The crystallization apparatus 20B configured in this way can crystallize beryllium chloride. The crystallized beryllium chloride is supplied from the crystallization tank 31 to the centrifuge 32, which will be described later, via valve V17.

[0191] Furthermore, as shown in Figure 10(b), the crystallization treatment tank 31 may be equipped with an electromagnetic wave generating unit 31a and a waveguide 31b instead of the hot water supply valve V16. The electromagnetic wave generating unit 31a and the waveguide 31b are configured similarly to the electromagnetic wave generating unit 22a and waveguide 22b shown in Figure 9, and are examples of induction heating devices.

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

[0193] (Dehydration equipment 20C) As shown in Figure 10(a), the dehydration apparatus 20C comprises a centrifugal separator 32 and a dryer 33. The dehydration apparatus 20C also includes a control unit, which is not shown in Figure 10(a). The control unit controls the centrifugal separator 32 and the dryer 33, respectively.

[0194] The beryllium chloride crystallized by the crystallization apparatus 20B is dehydrated using a centrifuge 32. The dehydrated beryllium chloride is then dehydrated using a dryer 33. An example of a dryer 33 is a hot air generation mechanism that generates hot air, and the hot air generated by this mechanism is used to heat and dehydrate the beryllium chloride. In other words, the crystallization apparatus 20B and the dehydration apparatus 20C are examples of dehydration apparatuses described in the claims, and can be used to carry out the dehydration step S21 of the manufacturing method M20 shown in Figure 2. The hot air is an example of a heating means employing an external heating method.

[0195] The dryer 33 may also be equipped with an electromagnetic wave generating unit 33a and a waveguide 33b instead of a hot air generating mechanism that generates hot air (see Figure 10(c)). The electromagnetic wave generating unit 33a and the waveguide 33b are configured similarly to the electromagnetic wave generating unit 22a and waveguide 22b shown in Figure 9, and are examples of induction heating devices.

[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 Figure 10(a), or an induction heating method as shown in Figure 10(c). From the viewpoint of energy efficiency, it is preferable to adopt an induction heating method.

[0197] (Electrolyzer 20D) As shown in Figure 10(a), the electrolytic apparatus 20D comprises an electrolytic furnace 34a, a power supply 34b, an anode 34c, a cathode 34d, and a feeder F2. The electrolytic furnace 34a also includes a heater, which is not shown in Figure 10(a). The electrolytic apparatus 20D also includes a control unit, which is not shown in Figure 10(a). The control unit controls the power supply 34b, the heater, and the feeder F2, respectively.

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

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

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

[0201] The control unit, while the binary bath is molten, uses the power supply 34b to pass an electric current between the anode 34c and the cathode 34d. As a result, the binary bath is electrolyzed, and metallic beryllium is generated on the surface of the cathode 34d.

[0202] As described above, the electrolytic device 20D can perform the electrolysis step S22 of the manufacturing method M20 shown in Figure 2.

[0203] [Other Embodiments] In the seventh embodiment described above, a beryllium production system 20 using a production apparatus 20A, a crystallization apparatus 20B, and an anhydrous apparatus 20C was described, and the production system 20 implements the production method M20.

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

[0205] The beryllium hydroxide production system comprises a production apparatus 20A shown in Figure 9, and a neutralization apparatus that produces beryllium hydroxide by neutralizing the beryllium chloride solution generated by the production apparatus 20A with a base. The neutralization apparatus can be composed of components corresponding to, for example, the container 24, valves V4 and V5, and centrifuge 25 shown in Figure 9. Ammonia may be used as the base for neutralization instead of sodium hydroxide.

[0206] The beryllium oxide production system comprises a production apparatus 20A shown in Figure 9, and a third heating apparatus that produces beryllium oxide by heating the beryllium chloride solution generated by the production apparatus 20A. The third heating apparatus is not limited to, but for example, an electric furnace can be used.

[0207] Furthermore, in the sections on (Modifications of the method for producing beryllium solution) and (Method for producing lithium solution), it was explained that when beryllium ore (e.g., beryl) or lithium ore (e.g., stearate) is used as the starting material, the sodium hydroxide addition step S16, the second filtration step S17, and the hydrochloric acid addition step S18 can be omitted. Therefore, when using the production apparatus 20A and using beryllium ore or lithium ore as the starting material, the configurations for carrying out the sodium hydroxide addition step S16, the second filtration step S17, and the hydrochloric acid addition step S18 can be omitted. In other words, the beryllium solution or lithium solution supplied from valve V3, obtained by the first filtration step S15, can be supplied directly to container 27.

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

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

[0210] (Method for producing lithium hydroxide M70) As shown in Figure 11(a), the lithium hydroxide production method M70 includes a drying step S71. The drying step S71 is a step in which the solution separated by the second filtration step S17 is evaporated and the precipitated lithium hydroxide is dried. By carrying out the lithium hydroxide production method M70, solid lithium hydroxide can be obtained.

[0211] (M80 method for manufacturing lithium carbonate) As shown in Figure 11(b), the lithium carbonate manufacturing method M80 includes a carbon dioxide introduction step S81, a fourth filtration step S82, and a drying step S83.

[0212] The carbon dioxide introduction step S81 is a step in which carbon dioxide is introduced into the solution separated by the second filtration step S17, thereby precipitating lithium carbonate in the solution.

[0213] The fourth filtration step S82 is performed after the carbon dioxide introduction step S81. The fourth filtration step S82 is a step in which lithium carbonate precipitated in the solution is separated from the solution using a filter.

[0214] The drying step S83 is performed after the fourth filtration step S82. The drying step S83 is a step in which the lithium carbonate separated by the fourth filtration step S82 is dried.

[0215] By implementing the lithium carbonate manufacturing method M80, solid lithium carbonate can be obtained.

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

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

[0218] [Tenth Embodiment] A method for producing lithium carbonate (Li2CO3) according to the tenth embodiment of the present invention, method M90, will be described with reference to Figure 12. Figure 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 Figure 12, the manufacturing method M90 includes a grinding and mixing step S12, a heating step S13, a dissolution step S14, a first filtration step S15, a sodium hydroxide addition step S16, a second filtration step S17, a carbon dioxide introduction step S91, a separation step S92, and a drying step S93.

[0220] The grinding and mixing process S12 to the second filtration process S17 in manufacturing method M90 is the same as the grinding and mixing process S12 to the second filtration process S17 in manufacturing method M10, except that the starting material is stearate. Therefore, in this embodiment, a detailed explanation of the grinding and mixing process S12 to the second filtration process S17 is omitted.

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

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

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

[0224] Furthermore, by performing 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. In addition, 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 introduction step S91 is the same step as the carbon dioxide introduction step S81 included in the lithium carbonate manufacturing method M80 shown in Figure 11(b). Therefore, in this embodiment, the explanation of the carbon dioxide introduction step S91 is omitted. By performing the carbon dioxide introduction step S91, a liquid phase containing lithium carbonate (Li2CO3), sodium chloride, and sodium carbonate (Na2CO3) is obtained.

[0226] Separation step S92 is a step in which lithium carbonate (Li2CO3) is separated from a liquid phase containing lithium carbonate (Li2CO3), sodium chloride, and sodium carbonate (Na2CO3). In separation step S92, a suspension in which lithium carbonate is dispersed can be obtained by concentrating the liquid phase containing lithium carbonate, sodium chloride, and sodium carbonate under reduced pressure. Such a suspension is also called a slurry. It is preferable to carry out the reduced pressure concentration at a temperature of 70°C or lower.

[0227] Furthermore, in separation step S92, the suspension described above is subjected to centrifugation. By performing centrifugation, the precipitated lithium carbonate can be precipitated. Thus, the lithium carbonate contained in the solid phase can be separated from the sodium chloride and sodium carbonate contained in the liquid phase.

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

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

[0230] <Variations of manufacturing method M90> In this embodiment, stearate was used as the starting material. However, the starting material used in manufacturing method M90 is not limited to stearate. 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, Y2O3). 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 utilized. As described in the explanation of manufacturing method M10, the hydroxide mixed with the starting materials in the grinding and mixing step S12 may be sodium hydroxide or potassium hydroxide. Furthermore, the liquid used to dissolve the liquid mixture in the dissolution step S14 may be an acid solution such as hydrochloric acid, sulfuric acid, or aqua regia, or it may be water.

[0232] As described above, by performing one modification of manufacturing method M90, a solution (e.g., an aluminum solution) in which inorganic substances constituting the oxide mineral or complex oxide are dissolved can be obtained using the oxide mineral or complex oxide as a starting material. If the oxide mineral or complex 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] [Embodiment 11] A lithium carbonate (Li2CO3) production method M100 according to the eleventh embodiment of the present invention will be described with reference to Figure 13. Figure 13 is a flowchart of the production method M100. In this embodiment, spodumene (LiAlSi2O6), an example of lithium ore, is used as the starting material.

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

[0235] The grinding and mixing process S12 to the first filtration process S15 in manufacturing method M100 are the same as the grinding and mixing process S12 to the first filtration process S15 in manufacturing method M90. Therefore, in this embodiment, a detailed explanation of the grinding and mixing process S12 to the first filtration process S15 is omitted.

[0236] The sodium bicarbonate addition step S1006 and the fifth filtration step S1007, 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. In addition, 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 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 (Na2CO3), and sodium bicarbonate (NaHCO3) 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 when it is concentrated under reduced pressure and centrifuged. This allows sodium bicarbonate, which has lower water solubility compared to sodium chloride and sodium carbonate, to be dissolved in the liquid phase.

[0238] Note that drying step S1009 is the same as drying step S93 in manufacturing method M90, so its explanation is omitted here.

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

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

[0241] As shown in Figure 14, the manufacturing method M110 includes a grinding and mixing step S12, a heating step S13, a dissolution 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 grinding and mixing steps S12 to the heating step S13 in manufacturing method M110 are the same as those in manufacturing method M10. Therefore, in this embodiment, a detailed explanation of the grinding and mixing steps S12 to the heating step S13 is omitted.

[0243] The dissolution step S14 in manufacturing method M110 is the same as the dissolution step S14 in manufacturing method M10, except that the acid solution used is sulfuric acid (H2SO4). Therefore, a detailed explanation of the dissolution step S14 is omitted in this embodiment. By carrying out the dissolution step S14, an acid solution is obtained that contains lithium, aluminum, and silicon ions contained in stearate, as well as sodium (Na) ions derived from sodium hydroxide.

[0244] By performing the first filtration step S15, 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 the manufacturing method M10. However, the third impurity removal step S1106 differs from the first impurity removal step S19 in that it uses a mixture of di(2-ethylhexyl) phosphoric acid (D2EHPA) and tributyl phosphate (TBP) as the organic compound, and further mixes sodium hydroxide (NaOH) with the above-mentioned organic compound. By performing the third impurity removal step S1106, lithium is adsorbed onto D2EHPA and TBP. That is, lithium is contained in the organic layer. On the other hand, aluminum, silicon, and sodium are contained in the aqueous layer without being adsorbed onto D2EHPA and TBP.

[0246] The first extraction step S1107 is a step of extracting the 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 in which an aqueous sulfuric acid solution is added to the organic layer obtained by carrying out the first extraction step S1107. By carrying out the sulfuric acid addition step S1108, the lithium adsorbed on D2EHPA and TBP forms lithium sulfide (Li2SO4) and moves from the organic layer to the aqueous layer. Therefore, the aqueous layer can 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 in which calcium hydroxide (Ca(OH)2) is added 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 together with hydroxide ions.

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

[0251] The separation step S1112 and drying step S1113 of manufacturing method M110 correspond to the separation step S92 and drying step S93 of manufacturing method M90. In separation step S1112, as in separation step S92, the solution containing lithium ionized together with hydroxide ions is subjected to reduced pressure concentration and centrifugation. By performing separation step S1112, a suspension in which lithium hydroxide is dispersed is obtained. Note that drying step S1113 is the same as drying step S93 of manufacturing method M90, so its explanation is omitted here.

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

[0253] In addition, for the aqueous layer containing lithium sulfide obtained by implementing the second extraction step S1109, solid lithium sulfide can be obtained by implementing separation and drying steps similar to the separation step S1112 and the drying step S1113.

[0254] 〔13th Embodiment〕 The lithium carbonate (Li2CO3) production method M120 according to the 13th embodiment of the present invention will be described with reference to FIG. 15. FIG. 15 is a flowchart of the production method M…

[0255] As shown in FIG. 15, the production method M120 includes a pulverization / mixing step S1202, a heating step S1203, a dissolution step S1204, a first filtration step S1205, a carbon dioxide gas introduction step S1206, a separation step S1208, and a drying step S1209.

[0256] The pulverization / mixing step S1202 and the heating step S1203 in the production method M120 are the same as the pulverization / mixing step S12 and the heating step S13 in the production method M90. Therefore, in this embodiment, detailed descriptions of the pulverization / mixing step S1202 and the heating step S1203 are omitted.

[0257] The dissolution step S1204 is a step of dissolving the liquid mixture obtained in the heating step S1203 in water (H2O). By implementing the dissolution step S1204, an aqueous sodium hydroxide solution in which lithium (Li) and silicon (Si) are dissolved and containing precipitated aluminum hydroxide is obtained.

[0258] The first filtration step S1205 is a step in which the solid phase and liquid phase contained in the sodium hydroxide aqueous solution obtained in the dissolution step S1204 are separated 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 introduction step S1206 is a step in which carbon dioxide gas is introduced into the aqueous sodium hydroxide solution separated by the first filtration step S1205. By performing the carbon dioxide gas introduction step S1206, lithium and sodium each form the 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, as in separation step S92, a solution containing lithium carbonate, sodium carbonate, and silicate ions is subjected to vacuum concentration and centrifugation. By performing separation step S1208, a suspension in which lithium carbonate is dispersed is obtained. Note that drying step S1209 is the same as drying step S93 of manufacturing method M90, so its explanation is omitted here.

[0261] As described above, by carrying out the lithium carbonate manufacturing method M120, solid lithium carbonate can be obtained even when using stearate as the starting material and using water instead of an acid solution in the dissolution step S1204.

[0262] [Embodiment 14] A method for producing lithium hydroxide (LiOH) according to the 14th embodiment of the present invention, M130, will be described with reference to Figure 16. Figure 16 is a flowchart of the production method M130. In this embodiment, spodumene (LiAlSi2O6), an example of lithium ore, is used as the starting material.

[0263] As shown in Figure 16, the manufacturing method M130 includes a grinding and mixing step S1202, a heating step S1203, a dissolution 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 grinding and mixing process S1202 to the first filtration process S1205 in manufacturing method M130 are the same as the grinding and mixing process S1202 to the first filtration process S1205 in manufacturing method M120. Therefore, in this embodiment, a detailed explanation of the grinding and mixing process S1202 to the first filtration process S1205 is 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 it uses a mixture of thenoyltrifluoroacetone (TTA) and tributyl phosphate (TBP) as the organic substance, and further mixes hydrochloric acid (HCl) with the above-mentioned organic substance. By performing the fourth impurity removal step S1306, lithium is adsorbed onto TTA and TBP. That is, lithium is contained in the organic layer. On the other hand, aluminum, silicon, and sodium are contained in the aqueous layer without being adsorbed onto TTA and TBP.

[0266] The first extraction step S1107 to drying step S1113 in manufacturing method M130 is the same as the first extraction step S1107 to drying step S1113 in manufacturing method M110. Therefore, in this embodiment, a detailed explanation of the first extraction step S1107 to drying step S1113 is omitted.

[0267] As described above, by carrying out the lithium hydroxide production method M130, solid lithium hydroxide can be obtained even when using stearate as the starting material and using water instead of an acid solution in the dissolution step S1204.

[0268] Furthermore, solid lithium sulfide can be obtained by performing the same separation and drying steps as in the separation step S1112 and drying step S1113 on the aqueous layer containing lithium sulfide obtained by carrying out the second extraction step S1109.

[0269] [Embodiment 15] A method for producing nickel compounds, M140, according to the 15th embodiment of the present invention, will be described with reference to Figure 17. Figure 17 is a flowchart of the production method M140. In this embodiment, nickel sludge is used as the starting material. Nickel sludge is a form of metal scrap, and is the slag produced when nickel is refined. Thus, metal scrap can be used as the starting material in the production method M140. Note that nickel sludge contains elements other than nickel (Ni) (for example, fluorine (F) and sulfur (S)). Therefore, nickel sludge is an example of a nickel compound. However, the starting material used in the production method M140 is not limited to nickel sludge, but may be metal produced in the manufacturing or processing of machinery or electronic components, or a compound containing such metal.

[0270] In manufacturing method M140, instead of dissolving the nickel contained in the nickel sludge in a solution (acidic 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 considered a method for purifying nickel compounds.

[0271] As shown in Figure 17, the manufacturing method M140 includes a grinding and mixing step S1402, a heating step S1403, a dissolution step S1404, and a first filtration step S1405.

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

[0273] The heating step S1403, the dissolution step S1404, and the first filtration step S1405 are each the same as the heating step S13, the dissolution step S14, and the first filtration step S15 of the manufacturing method M10, respectively. Therefore, in this embodiment, a detailed explanation of the heating step S1403, the dissolution step S1404, and the first filtration step S1405 is omitted.

[0274] In the dissolution step S1404, water is used as the liquid to dissolve the liquid mixture obtained in the heating step S1403. In this embodiment, since the sodium hydroxide contained in the liquid mixture dissolves in water, the solution obtained in the dissolution step S1404 is an aqueous sodium hydroxide solution containing the starting materials. By carrying out the dissolution step S1404, the fluorine and sulfur contained in the nickel sludge dissolve in the aqueous sodium hydroxide solution.

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

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

[0277] Note that the production method M140 can also be implemented again for the solid phase obtained by implementing the first filtration step S1405 (i.e., the nickel sludge purified once). By repeatedly implementing the production method M140 two or more times, the purity of nickel in the obtained nickel sludge can be further increased.

[0278] 〔16th Embodiment〕 The iron separation method M150 according to the 16th 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, ferberite (FeWO4) is used as the starting material. Ferberite is an example of a tungstate mineral.

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

[0280] The pulverization / mixing step S1502 is a step corresponding to the pulverization / mixing step S12 in the production method M10. That is, the pulverization / mixing step S1502 is a step of pulverizing the starting material and then mixing the starting material with the hydroxide powder. In this embodiment as well, the shape of sodium hydroxide is not limited to powder. In this embodiment, sodium hydroxide (NaOH) is used as the hydroxide. Thus, the pulverization / mixing step S1502 is the same as the pulverization / mixing step S​​The heating step S1503, the dissolution step S1504, and the first filtration step S1505 are each the same as the heating step S13, the dissolution step S14, and the first filtration step S15 of the manufacturing method M10, respectively. Therefore, in this embodiment, a detailed explanation of the heating step S1503, the dissolution step S1504, and the first filtration step S1505 is omitted.

[0282] In the dissolution step S1504, water is used as the liquid to dissolve the liquid mixture obtained in the heating step S1503. However, the liquid used in the dissolution step S1504 is not limited to water, but may be an acid solution (for example, hydrochloric acid solution and sulfuric acid solution). In this embodiment, since the sodium hydroxide contained in the liquid mixture dissolves in water, the solution obtained in the dissolution step S1504 is an aqueous sodium hydroxide solution containing the starting materials. By carrying out the dissolution step S1504, most of the tungsten (W) contained in the ferrous metal (for example, 90% or more) dissolves in the aqueous sodium hydroxide solution. Therefore, the solid phase contains iron oxide produced by the dissolution of tungsten from the ferrous metal.

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

[0284] The hydrochloric acid immersion step S1552 and the third filtration step S1553 are, respectively, the same steps as the hydrochloric acid immersion step S52 and the third filtration step S53 in the titanium and lithium separation method M50. Therefore, in this embodiment, a detailed explanation of the hydrochloric acid immersion step S1552 and the third filtration step S1553 is omitted.

[0285] By performing 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. Therefore, the hydrochloric acid solution after the hydrochloric acid immersion step S1552 contains iron chloride that was present in the liquid phase.

[0286] As described above, by implementing the iron separation method M150, tungsten and iron contained in ferrous metal can be separated.

[0287] In addition, in the dissolution step S1504, an acidic solution (for example, hydrochloric acid solution) can be used as the liquid to dissolve the liquid mixture obtained in the heating step S1503. In this case, the iron contained in the tungsten dissolves in the hydrochloric acid solution, while the tungsten contained in the tungsten remains in the solid phase. Thus, an acidic solution containing dissolved iron can be obtained simply by using an acidic solution in the dissolution step S1504.

[0288] [Examples] Examples of the present invention are described below. In the first and second examples described above, beryl and spodumine were used as the main starting materials, respectively. In the following examples, silicon oxide, nickel sludge, tunglite, monazite, apatite, xenotime, bauxite, magnetite, iron ore, rutile, and sphalerite were used as starting materials. In the examples where spodumine was used as a starting material, water was used as the liquid to dissolve the mixture in the dissolution step S14. The results for each example are summarized in Table 1. Table 1 includes the results for the first and second examples.

[0289] [Table 1] In Table 1, a white circle indicates that at least some of the target elements to be dissolved from the starting materials have been dissolved, and an "X" indicates that the target elements have not been dissolved.

[0290] <Third Example> In the third embodiment, the grinding and mixing steps S12 to the dissolution step S14 of the manufacturing method M90 shown in Figure 12 were carried out. In this embodiment, high-purity silicon dioxide (SiO2) reagent was used as the starting material. In this embodiment, sodium hydroxide was used as the hydroxide mixed in the grinding 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 set to 1:10. In the heating step S13, dielectric heating was performed in a dielectric heating device 10 under atmospheric pressure and in an air atmosphere. The heating temperature in the heating step S13 was set to 300°C and the heating time was set to 8 minutes. By performing the heating step S13, the powdered mixture melted due to dielectric heating, and after 8 minutes, it became a completely emulsion-like liquid mixture. Hereafter, when it is not necessary to distinguish whether the mixture is in powder or liquid form, it will simply be referred to as the mixture. In this example, in the dissolution step S14, the experiment was conducted using either hydrochloric acid solution or water as the liquid to dissolve the mixture.

[0292] When hydrochloric acid solution was used as the liquid to dissolve the mixture, a precipitate of silicic acid (H2SiO4) was formed. It is thought that silicic acid was produced from the starting material, silicon oxide, through two reactions. The first reaction is the reaction of silicon oxide with sodium hydroxide to produce sodium silicate (Na2SiO4). Sodium silicate is water-soluble and therefore dissolves in the solution. However, in the second reaction, silicic acid is produced by the reaction of sodium silicate with hydrochloric acid. Since silicic acid is insoluble, a precipitate of silicic acid was formed in the solution. Furthermore, the fact that the two reactions described above proceeded when hydrochloric acid solution was used as the liquid to dissolve the mixture was confirmed by the fact that no precipitate was formed when water was used instead of hydrochloric acid. Therefore, in Table 1, the case in which silicon oxide was used as the starting material and hydrochloric acid solution was used as the liquid to dissolve the mixture is indicated by a white triangle.

[0293] Furthermore, when water was used as the liquid to dissolve the mixture, it is assumed that silicon was dissolved in the solution in the form of water-soluble sodium silicate. In this case, the solubility of silicon oxide was 90% or higher.

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

[0295] <Fourth set of examples> In the fourth group of examples, the grinding and mixing steps S12 to the dissolution step S14 of the manufacturing method M90 shown in Figure 12 were carried out, similar to the third example. In this group of examples, aluminum oxide (Al2O3) was used as the starting material. In this group of examples, aluminum oxide was adopted as the starting material to mimic bauxite. In this group of examples, sodium hydroxide was used as the hydroxide mixed in the grinding and mixing step S12. In this group of examples, both hydrochloric acid solution and water were used as the liquid to dissolve the mixture in the dissolution step S14.

[0296] After the dissolution process S14, a cloudy solution was obtained regardless of whether hydrochloric acid solution or water was used as the liquid to dissolve the mixture. Analysis of these cloudy solutions revealed that aluminum oxide is soluble in both hydrochloric acid solution and water. The solubility of aluminum in hydrochloric acid solution was 99%, and the solubility of aluminum in water was 95%.

[0297] <Fifth group of examples> In the fifth group of examples, the grinding and mixing steps S12 to the dissolution step S14 of the manufacturing method M90 shown in Figure 12 were carried out in the same manner as in the third example. In this group of examples, titanium dioxide (TiO2) was used as the starting material. In addition, in this group of examples, the following combinations of hydroxides were used for mixing in the grinding and mixing step S12 and for dissolving the mixture in the dissolution step S14: (1) sodium hydroxide and hydrochloric acid solution, (2) sodium hydroxide and sulfuric acid solution, and (3) potassium hydroxide and sulfuric acid solution.

[0298] After the dissolution process S14, in all of the cases described above (1), (2), and (3), a cloudy solution containing residue was obtained. Analysis of the obtained residue revealed that titanium dioxide is soluble in acidic solutions. The solubility of titanium in each combination of (1), (2), and (3) was 25%, 50%, and 98%, respectively. Note that the column for titanium dioxide in Table 1 shows the results for case (3).

[0299] <Sixth set of examples> In the sixth group of examples, the grinding and mixing steps S12 to the dissolution step S14 of the manufacturing method M10 shown in Figure 1 were carried out. In this group of examples, beryllium oxide (BeO) was used as the starting material. In this group of examples, beryllium oxide was adopted as the starting material to mimic the beryllium oxide formed on the surface of beryllium, which is an example of a neutron multiplier. This is because beryllium is known to dissolve easily in acidic solutions, and beryllium oxide is formed on the surface of beryllium that has been used as a neutron multiplier.

[0300] Furthermore, in this group of embodiments, sodium hydroxide was used as the hydroxide mixed in the grinding and mixing step S12. In addition, in this group of embodiments, the process was carried out using either hydrochloric acid solution or water as the liquid to dissolve the mixture in the dissolution step S14.

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

[0302] <Seventh set of examples> In the seventh group of examples, the grinding and mixing steps S12 to the dissolution step S14 of the manufacturing method M10 shown in Figure 1 were carried out. In this group of examples, lithium titanate (Li2TiO3) was used as the starting material. Lithium titanate is an example of a tritium breeding material. In this group of examples, sodium hydroxide was used as the hydroxide mixed in the grinding and mixing step S12. In this group of examples, both sulfuric acid solution and water were used as the liquid to dissolve the mixture in the dissolution step S14.

[0303] After the dissolution process S14, a cloudy solution containing residue was obtained regardless of whether sulfuric acid solution or water was used as the liquid to dissolve the mixture. Analysis of the obtained residue revealed that lithium titanate is soluble in both sulfuric acid solution and water. The solubility of lithium in sulfuric acid solution was 97%, and the solubility of lithium in water was 19%.

[0304] <Examples 1, 2, and 8> As described in the first example, beryl was completely dissolved in the hydrochloric acid aqueous solution (99% beryllium dissolution was confirmed). Also, as described in the second example, spodumine was dissolved in the hydrochloric acid aqueous solution (more than 90% lithium dissolution was confirmed). Furthermore, as a modification of the first example, in the dissolution step S14, the liquid used to dissolve the liquid mixture was changed from hydrochloric acid aqueous solution to water. In this case, the solubility of beryllium contained in beryl was 56%.

[0305] Furthermore, in the eighth example, spodumine was used as the starting material, similar to the second example, and water was used as the liquid to dissolve the mixture. As a result, spodumine dissolved in water (96% lithium dissolution was confirmed).

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

[0307] After the dissolution process S14 was performed, a yellowish, cloudy solution was obtained. The results of the analysis of this solution are shown in Figure 19. Figure 19 is a graph showing the solubility of yttrium (Y), lanthanum (La), cerium (Ce), neodymium (Nd), samarium (Sm), terbium (Tb), and dysprosium (Dy) contained in monazite. According to Figure 19, yttrium showed a solubility of approximately 80%, lanthanum, neodymium, samarium, terbium, and dysprosium each showed a solubility of between 50% and 65%, and cerium showed a solubility of approximately 20%.

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

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

[0310] <Embodiment 11> In the 11th embodiment, similar to the third embodiment, the grinding and mixing process S12 to the dissolution process S14 of the manufacturing method M90 shown in Figure 12 were carried out. In this embodiment, xenotime (YPO4) was used as the starting material. In this embodiment, sodium hydroxide was used as the hydroxide mixed in the grinding and mixing process S12. In this embodiment, the heating temperature in the heating process S13 was set to 250°C. In this embodiment, hydrochloric acid solution was used as the liquid to dissolve the mixture in the dissolution process S14.

[0311] After the dissolution process S14, the solubility of xenotime was approximately 50%.

[0312] <Examples 12 and 13> In the 12th and 13th examples, the grinding and mixing steps S12 to the dissolution step S14 of the manufacturing method M90 shown in Figure 12 were carried out, similar to the 3rd example. In the 12th and 13th examples, magnetite (Fe3O4) and iron ore (Fe2O3) were used as starting materials, respectively. In these examples, sodium hydroxide was used as the hydroxide mixed in the grinding and mixing step S12. In these examples, the heating temperature in the heating step S13 was set to 250°C. In these examples, hydrochloric acid solution was used as the liquid to dissolve the mixture in the dissolution step S14.

[0313] Analysis of the residue obtained after the dissolution process S14 revealed that the solubility of magnetite was over 90%, and the solubility of iron ore was also over 90%. Furthermore, when magnetite was used as the starting material and water was used as the liquid to dissolve the mixture, the magnetite did not dissolve.

[0314] <Example 14> In the 14th embodiment, the grinding and mixing process S12 to the dissolution process S14 of the manufacturing method M90 shown in Figure 12 were carried out, similar to the third embodiment. In this embodiment, molybdenum (MoS2) was used as the starting material. In this embodiment, sodium hydroxide was used as the hydroxide mixed in the grinding and mixing process S12. In this embodiment, the heating temperature in the heating process S13 was set to 250°C. In this embodiment, the liquids used to dissolve the mixture in the dissolution process S14 were (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.

[0315] After performing the dissolution process S14, the resulting residue was analyzed, and the solubility of molybdenum was 25%, 44%, 62%, and 65% for each of (1) to (4), respectively. Note that the column for molybdenum in Table 1 shows the results for cases (3) and (4).

[0316] <Examples 15> In the 15th group of examples, the grinding and mixing steps S12 to the dissolution step S14 of the manufacturing method M90 shown in Figure 12 were carried out, similar to the third example. In this group of examples, zincblende ((Zn,Fe)S) was used as the starting material. In this group of examples, sodium hydroxide was used as the hydroxide mixed in the grinding and mixing step S12. In this group of examples, both hydrochloric acid solution and water were used as the liquid to dissolve the mixture in the dissolution step S14.

[0317] After the dissolution process S14, a turbid solution containing residue was obtained regardless of whether hydrochloric acid solution or water was used as the liquid to dissolve the mixture. Analysis of the obtained residue revealed that sphalerite is soluble in both hydrochloric acid solution and water. The solubility of sphalerite in hydrochloric acid solution was over 90%, and the solubility of sphalerite in water was over 80%.

[0318] <Examples 16 and 17> In the 16th embodiment, similar to the third embodiment, the grinding and mixing process S12 to the dissolution process S14 of the manufacturing method M90 shown in Figure 12 were carried out. In this embodiment, tungsten (FeWO4) was used as the starting material. In this embodiment, sodium hydroxide was used as the hydroxide mixed in the grinding and mixing process S12. In this embodiment, hydrochloric acid solution was used as the liquid to dissolve the mixture in the dissolution process S14.

[0319] In the 17th embodiment, the separation method M150 shown in Figure 18 was carried out. In this embodiment, tungsten (FeWO4) was used as the starting material. In this embodiment, sodium hydroxide was used as the hydroxide mixed in the crushing and mixing step S12. In this embodiment, water was used as the liquid to dissolve the mixture in the dissolution step S14.

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

[0321] In the 17th example, after performing the dissolution step S1504, a turbid solution containing residue was obtained. Analysis of the obtained residue revealed that the solubility of tungsten contained in ferrous metal was 90% or more. However, in this turbid solution, iron-containing compounds precipitated as residue. Next, the hydrochloric acid immersion 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 ferrous metal was 90% or more.

[0322] <Example 18> In the 18th embodiment, similar to the third embodiment, the grinding and mixing process S12 to the dissolution process S14 of the manufacturing method M90 shown in Figure 12 were carried out. In this embodiment, cobalt-rich crust was used as the starting material. In this embodiment, potassium hydroxide was used as the hydroxide mixed in the grinding and mixing process S12. In this embodiment, hydrochloric acid solution was used as the liquid to dissolve the mixture in the dissolution process S14.

[0323] In the 18th example, a solution containing a small amount of residue was obtained after the dissolution step S14. Analysis of this residue revealed that the solubility of the cobalt-rich crust was approximately 95%.

[0324] <Examples 19> In the 19th group of examples, the grinding and mixing process S12 to the dissolution process S14 of the manufacturing method M90 shown in Figure 12 were carried out, similar to the third example. In this group of examples, manganese nodules were used as the starting material. In this group of examples, sodium hydroxide and potassium hydroxide were used as the hydroxides mixed in the grinding and mixing process S12. In this group of examples, the heating temperature in the heating process S13 was set to 250°C. In this group of examples, hydrochloric acid and water were used as the liquids to dissolve the mixture in the dissolution process S14. The combinations of hydroxide and liquid adopted were (1) sodium hydroxide and hydrochloric acid solution, (2) sodium hydroxide and water, and (3) potassium hydroxide and hydrochloric acid solution. Note that the column for manganese nodules in Table 1 shows the cases of (2) and (3).

[0325] After the dissolution process S14 was performed, a solution containing the residue was obtained in all of the cases described above as (1), (2), and (3). Analysis of the residue for each of (1), (2), and (3) revealed that the solubility of the manganese nodules was approximately 56%, 27%, and 85%, respectively.

[0326] <Examples 20> In the 20th group of examples, the manufacturing method M140 shown in Figure 17 was carried out. In this group of examples, nickel sludge was used as the starting material. In this group of examples, sodium hydroxide and potassium hydroxide were used as the hydroxides to be mixed in the grinding and mixing step S12. In this group of examples, water was used as the liquid to dissolve the mixture in the dissolution step S14. In addition, in the 20th group of examples, after carrying out the manufacturing method M140, the 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 dissolution step S1404. Analysis of this yellowish solution revealed a fluoride ion concentration of 16.7% and a sulfur ion concentration of 3.4%. Nickel was not detected. Analysis of the solution obtained after the second dissolution step S1404 revealed a fluoride ion concentration of 0.5% and a sulfur ion concentration of 0.3%.

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

[0329] As described above, it was found that by implementing manufacturing method M140, fluoride ions and sulfur ions contained in the starting material, nickel sludge, can be dissolved into the solution, thereby increasing the purity of 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 obtaining a liquid mixture containing an inorganic substance by dielectric heating a powdered mixture obtained by mixing an inorganic powder with a hydroxide. In this production method, the shape of the hydroxide is not limited.

[0331] The hydroxyl groups contained in hydroxides absorb electromagnetic waves used in dielectric heating, converting the energy of the electromagnetic waves into their own thermal energy. In the heating step of this manufacturing method, inorganic powder and hydroxide powder are mixed, so the thermal energy of the hydroxide is efficiently supplied to the inorganic material as well. As a result, a liquid mixture of molten inorganic material and hydroxide can be obtained. This liquid mixture dissolves readily in acid solutions. Therefore, an inorganic solution can be produced using this liquid mixture.

[0332] Furthermore, in the heating process, high-temperature treatment (e.g., 770°C, 1650°C, or 2000°C) is unnecessary, as in the sintering or melting treatment described in Non-Patent Literature 1. A liquid mixture can be obtained simply by performing dielectric heating on the powdered mixture. Therefore, this manufacturing method is more energy-efficient than the manufacturing method described in Non-Patent Literature 1.

[0333] As described above, this manufacturing method is a method for producing solutions of inorganic substances that are difficult to dissolve in both basic and acidic solutions, such as beryllium ore, and can provide a novel manufacturing method that is highly energy-efficient.

[0334] Furthermore, in the method for producing an inorganic solution according to the 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 is configured to contain at least one of beryllium and lithium.

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

[0336] Furthermore, in the method for producing an inorganic solution according to the 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, the hydroxide is at least one of sodium hydroxide and potassium hydroxide.

[0337] As such, examples of hydroxides include sodium hydroxide and potassium hydroxide. A mixture of sodium hydroxide and potassium hydroxide may also be used as the hydroxide.

[0338] Furthermore, in the method for producing an inorganic solution according to the 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 dissolution step is further included in which the liquid mixture obtained in the heating step is dissolved in an acid solution or water to obtain an acid solution of the inorganic substance.

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

[0340] Furthermore, in the method for producing an inorganic solution according to the 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 dielectric heating the powdered mixture under normal pressure.

[0341] Thus, in the heating step of this manufacturing method, a liquid mixture can be obtained without dielectric heating while pressurizing the powdered mixture. Therefore, the manufacturing apparatus for implementing this manufacturing method can be easily constructed, and the effort required to obtain approval for the plant where the manufacturing apparatus is installed can be reduced.

[0342] An apparatus for producing an inorganic solution according to a sixth aspect of the present invention comprises a mixing unit that obtains a powdered mixture of an inorganic substance and a hydroxide by mixing an inorganic powder with a hydroxide, a container for containing the powdered mixture, and an electromagnetic wave generating unit 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 embodiment described above. The shape of the hydroxide mixed with the inorganic powder in the mixing section of this manufacturing apparatus is not limited.

[0344] Furthermore, 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, the inorganic substance is configured to include at least one of beryllium and lithium.

[0345] According to the above configuration, the same effects as the method for producing an inorganic solution according to the second embodiment described above are achieved.

[0346] Furthermore, in the inorganic solution manufacturing apparatus according to the 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, the hydroxide is at least one of sodium hydroxide and potassium hydroxide.

[0347] The above configuration provides the same effects as the method for producing an inorganic solution according to the third embodiment described above. A mixture of sodium hydroxide and potassium hydroxide may be used as the hydroxide.

[0348] Furthermore, in the inorganic solution manufacturing apparatus according to the ninth aspect of the present invention, in addition to the configuration of the inorganic solution manufacturing apparatus according to any one of the sixth to eighth aspects described above, a waveguide is interposed between the electromagnetic wave generating unit and the container to guide the electromagnetic waves from the electromagnetic wave generating unit to the container, and an isolator is provided in the middle section of the waveguide to absorb electromagnetic waves propagating from the container toward the electromagnetic wave generating unit is adopted.

[0349] With the above configuration, even if some of the electromagnetic waves generated by the electromagnetic wave generator return from the container towards the electromagnetic wave generator, the isolator can absorb such electromagnetic waves. Therefore, adverse effects on the operation of the electromagnetic wave generator can be suppressed.

[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 liquid supply unit for supplying an acid solution or water to the container is further provided.

[0351] According to the above configuration, the same effects as those of the method for producing an inorganic solution according to the fourth embodiment described above are achieved.

[0352] [Additional Notes] The present invention is not limited to the embodiments described above, 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 (Method for Manufacturing Inorganic Solutions) S13 Heating process S14 Melting process 10,22 Dielectric heating apparatus (equipment for manufacturing inorganic solutions) 11,22a Electromagnetic wave generation unit 12,22b waveguide 14,22c container 18 Isolators

Claims

1. A heating step of dielectric heating a first mixture, which is a powder mixture obtained by mixing an inorganic powder containing at least one of beryllium and lithium with a hydroxide which is at least one of sodium hydroxide and potassium hydroxide, The process includes a dissolution step of dissolving a second mixture, which is a liquid mixture obtained in the heating step, or a mixture containing the liquid mixture and a solid mixture obtained from the liquid mixture, in a hydrochloric acid solution, sulfuric acid solution, nitric acid solution, or water to obtain a solution of the inorganic substance. A method for producing an inorganic solution, characterized by the following:

2. The heating step is a step of dielectric heating the first mixture under normal pressure. A method for producing an inorganic solution according to feature 1.

3. The heating temperature in the heating step is below the melting point of the hydroxide. A method for producing an inorganic solution according to feature 1 or 2.

4. A mixing unit that obtains a first mixture, which is a powdered mixture, by mixing an inorganic powder containing at least one of beryllium and lithium with a hydroxide which is at least one of sodium hydroxide and potassium hydroxide. A container for containing the first mixture, An electromagnetic wave generating unit generates electromagnetic waves for dielectric heating the first mixture in the container to obtain a second mixture which is a liquid mixture, or a mixture containing the liquid mixture and a solid mixture obtained by changing the liquid mixture. The system includes a liquid supply unit for supplying hydrochloric acid solution, sulfuric acid solution, nitric acid solution, or water into the container to dissolve the second mixture in the container and obtain the inorganic solution. An apparatus for producing inorganic solutions, characterized by the features described above.

5. A waveguide is interposed between the electromagnetic wave generating unit and the container, and guides the electromagnetic waves from the electromagnetic wave generating unit to the container. The waveguide further comprises an isolator provided in an intermediate section of the waveguide, which absorbs electromagnetic waves propagating from the container toward the electromagnetic wave generating section. The apparatus for producing an inorganic solution according to feature 4.

6. A thermometer for measuring the temperature inside the container, The system further comprises a control unit for controlling 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 generating unit so that the temperature of the first mixture is below the melting point of the hydroxide. The apparatus for producing an inorganic solution according to feature 4 or 5.

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