Method for producing beryllium solution, method for producing beryllium, method for producing beryllium hydroxide, method for producing beryllium oxide, and method for producing beryllium oxide

Abstract

The purpose of the present invention is to provide a novel method for producing a beryllium solution by dissolving a beryllium oxide, the method being highly energy efficient. This method (M10) for producing a beryllium solution includes a primary heating step (S13) for producing a beryllium solution through induction heating of an acidic solution containing a beryllium oxide.

Description

[Technical field]

[0001] The present invention relates to a method for producing a beryllium solution from beryllium oxide.The present invention also relates to a method for producing beryllium, beryllium hydroxide and beryllium oxide, and to beryllium oxide. [Background technology]

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

[0003] When producing beryllium, a compound containing beryllium, or an alloy containing beryllium, first, beryllium is extracted from the beryllium ore by dissolving the beryllium ore in a solvent. However, it is not easy to dissolve the beryllium ore in a solvent. Although an acidic solution such as sulfuric acid is known as a solvent that easily dissolves beryllium ore, beryllium ore is difficult to dissolve even in an acidic solution.

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

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

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

[0007] One aspect of the present invention has been made in consideration of the above-mentioned problems, and an object of the present invention is to provide a novel method for producing a beryllium solution by dissolving beryllium oxide, which method has high energy efficiency. [Means for solving the problem]

[0008] A method for producing a beryllium solution according to one aspect of the present invention includes a main heating step of producing a beryllium solution by dielectrically heating an acidic solution containing beryllium oxide.

[0009] A method for producing beryllium according to one embodiment of the present invention includes the steps included in the method for producing a beryllium solution according to one embodiment of the present invention, as well as a dehydration step of producing a beryllium salt by dehydrating the beryllium solution, and an electrolysis step of producing beryllium by subjecting the beryllium salt to molten salt electrolysis.

[0010] A method for producing beryllium hydroxide according to one embodiment of the present invention includes the steps included in the method for producing a beryllium solution according to one embodiment of the present invention, and a neutralization step of producing beryllium hydroxide by neutralizing the beryllium solution with a base.

[0011] A method for producing beryllium oxide according to one embodiment of the present invention includes each step included in the method for producing a beryllium solution according to one embodiment of the present invention, and a third heating step of producing beryllium oxide by heating the beryllium solution.

[0012] A beryllium oxide according to one embodiment of the present invention is a crystalline beryllium oxide having a plurality of recesses formed on its surface, and some or all of the plurality of recesses have opening shapes that reflect the shape of the unit lattice of the crystal. Effect of the Invention

[0013] According to one aspect of the present invention, there is provided a novel method for producing a beryllium solution by dissolving beryllium oxide, which method has high energy efficiency. [Brief description of the drawings]

[0014] [Figure 1] 1 is a flowchart showing a method for producing a beryllium chloride solution according to a first embodiment of the present invention. [Diagram 2] 5 is a flowchart showing a method for producing beryllium, a method for producing beryllium hydroxide, and a method for producing beryllium oxide according to a second embodiment of the present invention. [Diagram 3] 1 is a schematic diagram of a heating device for carrying out a pre-heating step and a main heating step included in a method for producing a beryllium solution according to an embodiment of the present invention. [Figure 4] 1 is a table summarizing the experimental conditions for Experiments 1 to 6 including the examples of the present invention and the comparative examples. [Diagram 5] 10 is a graph showing a change in temperature of a container in a main heating step included in one embodiment of the present invention. [Figure 6] 1 is a micrograph of beryl before and after a preheating step in one embodiment of the present invention; [Figure 7] 5 is a table summarizing the amounts of dissolved Be, Al, and Si in Experiments 1 to 6 shown in FIG. [Figure 8] 5 is a table summarizing the results of Experiments 1 to 6 shown in FIG. 4. [Figure 9]5 is a graph showing the correlation between the maximum temperature of the acid solution and the solubility of beryllium when the main heating step is carried out for the phenasite of Experiment 4 and the beryl of Experiment 6 shown in FIG. 4. [Figure 10] 5 is a table showing the amount of each element dissolved in Experiments 1 to 6, which are additional experiments among Experiments 1 to 6 shown in FIG. 4. [Figure 11] 5 is a table summarizing the results of Experiments 1 to 6, which are additional experiments to those shown in FIG. 4 . DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] [First embodiment] (M10: Beryllium Solution Manufacturing Method) A method for producing a beryllium solution M10 according to a first embodiment of the present invention will be described with reference to FIG. 1. FIG. 1 is a flow chart of the method for producing a beryllium solution M10. In the following, the method for producing a beryllium solution M10 will also be simply referred to as the manufacturing method M10. In this embodiment, a method for producing a BeCl2 solution, which is an aqueous solution of beryllium chloride (BeCl2), which is a hydrochloride of beryllium, will be described. However, the beryllium solution produced using the manufacturing method M10 is not limited to a BeCl2 solution, and may be a BeSO4 solution, which is an aqueous solution of beryllium sulfate (BeSO4), which is a sulfate of beryllium, a Be(NO3)2 solution, which is an aqueous solution of beryllium nitrate (Be(NO3)2), which is a nitrate of beryllium, a beryllium fluoride (BeF2), which is a hydrofluoride of beryllium, a beryllium bromide (BeBr2), which is a hydrobromide of beryllium, or a beryllium iodide (BeI2), which is a hydroiodide of beryllium.

[0016] As shown in FIG. 1, the manufacturing method M10 includes a crushing step S11, a preheating step S12, a main heating step S13, a first impurity removal step S14, and a second impurity removal step S15, and uses beryllium ore as a raw material for producing a beryllium solution. Beryllium ore is a general term for ores containing beryllium, and is also an example of beryllium oxide. Beryllium ore has crystallinity. Beryllium ore is mainly classified into Be-Si-O ores containing beryllium and silicon, and Be-Si-Al-O ores containing beryllium, silicon, and aluminum. Examples of Be-Si-O ores include bertrandite and phenacite, and examples of Be-Si-Al-O ores include beryl and chrysoberyl. In this embodiment, the manufacturing method M10 is described using beryl as an example of a raw material.

[0017] The crushing step S11 is a step of crushing the beryl lump into granules. The technique used to crush the beryl is not limited and can be appropriately selected from existing techniques, such as a hammer or a ball mill. The technique used to crush the beryl may also be a combination of a plurality of techniques (e.g., a hammer and a ball mill). In this case, a hammer may be used in the first stage of the crushing step S11, and a ball mill may be used in the second stage.

[0018] If the beryl can be crushed finer, the ratio of the surface area to the total volume of the beryl can be increased, and it is expected that the time required for dissolving the beryllium contained in the beryl in the solution in the pre-heating step S12 and the main heating step S13 described below can be shortened. On the other hand, if the beryl is crushed too finely, the time and cost required for the crushing step S11 will increase. Therefore, it is preferable to determine the particle size of the beryl obtained after the crushing step S11 is carried out, taking into consideration the time required for the pre-heating step S12 and the main heating step S13, the time required for the crushing step S11, the cost required for the crushing step S11, and the like.

[0019] The particle size of beryl may be any of the average size, mode size, and median size. When the particle size distribution of beryl is measured, the average size is the particle size that is the average value of the obtained particle size distribution, the mode size is the most frequent particle size in the particle size distribution, and the median size is the particle size where the cumulative frequency in the particle size distribution is 50%.

[0020] In this embodiment, the pulverization step S11 is carried out so that the average diameter of the beryl becomes 100 μm.

[0021] (Preheating step S12) The preliminary heating step S12 is a step performed before the main heating step S13 described later, and is a step of dielectrically heating a basic solution containing beryl. The basic solution is not particularly limited, but an aqueous solution of sodium hydroxide (NaOH) or potassium hydroxide (KOH), which is a basic solute, can be used. In this embodiment, a NaOH solution is used as the basic solution. The concentration of NaOH in the NaOH solution can be appropriately adjusted, but it is preferable that the pH is adjusted to 14 or more.

[0022] Dielectric heating is a general term for a technology that heats an object by applying electromagnetic waves having a specific frequency to the object, and is also called high-frequency heating or microwave heating depending on the band of the electromagnetic waves applied. For example, high-frequency heating applies electromagnetic waves (so-called short waves or ultra-short waves) in the band of 3 MHz or more and less than 300 MHz to the object, while microwave heating applies electromagnetic waves (so-called microwaves) in the band of 300 MHz or more and less than 30 GHz to the object. Microwave ovens, which are widely used in homes, are an example of a device that can perform microwave heating.

[0023] In this embodiment, in the preheating step S12, electromagnetic waves having a frequency of 2.45 GHz are applied to the NaOH solution containing beryl. The configuration of an apparatus for applying electromagnetic waves to the NaOH solution containing beryl will be described later with reference to FIG.

[0024] By carrying out the pre-heating step S12 before carrying out the main heating step S13, a plurality of recesses are formed on the surface of the beryl. Some or all of these recesses have opening shapes that reflect the shape of the unit lattice of the crystal. The surface of the beryl on which the plurality of recesses are formed in this way is spare Heating process S 12 The surface of the beryl becomes weaker than that before the preliminary heating step S12. As a result, the beryl after the preliminary heating step S12 is dissolved in an acidic solution by carrying out the main heating step S13 described below. In this way, since the manufacturing method M10 includes the preliminary heating step S12, it is possible to dissolve Be-Si-Al-O ores (such as beryl and chrysoberyl) that are difficult to dissolve by carrying out the main heating step S13 alone. Therefore, it is possible to manufacture a beryllium chloride solution using not only Be-Si-O ores (such as bertrandite and phenacite) that are relatively easily soluble in an acidic solution, but also Be-Si-Al-O ores that are difficult to dissolve in an acidic solution as starting materials.

[0025] When a Be-Si-O based ore such as bertrandite is used as the raw material instead of a Be-Si-Al-O based ore such as beryl, the manufacturing method M10 may include or omit the preheating step S12.

[0026] As described above, the scope of the present invention also includes beryl after the preheating step S12 and a basic solution after the preheating step S12, which contains beryl, an example of beryllium oxide, and beryllium ions. This basic solution is an example of a beryllium solution.

[0027] As described above, beryl having a surface on which are formed a plurality of recesses whose opening shapes reflect the shape of the unit lattice of the crystal is dissolved in an acidic solution in the main heating step S13 described below. Therefore, the beryl after the preliminary heating step S12 is performed is suitable as a raw material for producing a beryllium solution.

[0028] In addition, Be-Si-Al-O ores such as beryl are difficult to melt when only the main heating step S13 is performed without performing the preliminary heating step S12. However, because a plurality of recesses are formed on the surface, even Be-Si-Al-O ores can be melted by performing the main heating step S13.

[0029] The heating temperature in the preheating step S12 can be set appropriately. However, the heating temperature in the preheating step S12 is preferably equal to or lower than the heat-resistant temperature of the container (for example, the container 14 described in the fifth embodiment) that contains the basic solution containing beryl. For example, when the container is made of polytetrafluoroethylene like the container 14, the heating temperature in the preheating step S12 is preferably equal to or lower than 250°C. When the material constituting the container has corrosion resistance against the basic solution and has a heat-resistant temperature exceeding 250°C, the heating temperature in the preheating step S12 may exceed 250°C. By increasing the heating temperature in the preheating step S12, it is highly likely that the time required for the preheating step S12 can be shortened. In addition, the heating temperature in the preheating step S12 is preferably equal to or higher than 180°C. By using the preheating step S12, which has a heating temperature of 180°C or higher, in combination with the main heating step S13 described later, a large amount of beryllium contained in the beryl can be dissolved in the solution. The heating time in the preheating step S12 can also be set appropriately, but is preferably, for example, 60 minutes or more.

[0030] (Main heating process S13) The main heating step S13 is a step performed after the pre-heating step S12, in which an acidic solution containing beryl is dielectrically heated to produce a beryllium solution, which is an acidic solution in which beryllium is dissolved.

[0031] The acidic solution is not particularly limited, but may be any aqueous solution of an acidic solute, such as hydrogen chloride (HCl), sulfuric acid (H2SO4), nitric acid (HNO3), hydrogen fluoride (HF), hydrogen bromide (HBr), or hydrogen iodide (HI). In this embodiment, an HCl solution is used as the acidic solution. The concentration of HCl in the HCl solution may be appropriately adjusted, but is preferably adjusted to a pH of 1 or less.

[0032] By adding an appropriate amount of HCl solution to the NaOH solution after the preliminary heating step S12, the basic solution containing beryllium becomes neutral and then an acidic solution containing beryllium.

[0033] The dielectric heating performed in the main heating step S13 is the same as the dielectric heating performed in the pre-heating step S12. That is, in this embodiment, an electromagnetic wave having a frequency of 2.45 GHz is applied to the HCl solution containing beryl.

[0034] By using dielectric heating to heat an acidic solution containing beryllium oxide, it is possible to dissolve beryllium oxide in the acidic solution with higher energy efficiency than before. Specifically, it is possible to obtain a hydrochloric acid solution in which beryllium chloride hydrate (BeCl2·xH2O) is dissolved. Therefore, manufacturing method M10 can provide a new manufacturing method with high energy efficiency.

[0035] The heating temperature in the main heating step S13 can be appropriately set, similar to the heating temperature in the pre-heating step S12. That is, when the container (for example, the container 14 described in the fifth embodiment) that holds the acidic solution containing beryl is made of polytetrafluoroethylene, the heating temperature in the main heating step S13 is preferably 250° C. or lower. Also, the heating temperature in the main heating step S13 is preferably 180° C. or higher. Also, main Heating process S 13 The heating time in the step can also be appropriately set, but is preferably, for example, 60 minutes or more.

[0036] (First impurity removal step S14) The first impurity removal step S14 is a step performed after the main heating step S13. The first impurity removal step S14 is a step of removing the first element from the BeCl2 solution obtained by the main heating step S13 using an organic compound that adsorbs the first element.

[0037] The first element to be removed in the first impurity removal step S14 is determined by the organic compound used here. Examples of organic compounds that can be used in the first impurity removal step S14 include tri-n-octylphosphine oxide (TOPO), di-(2-ethylhexyl) phosphoric acid (DEHPA), tri-n-butyl phosphate (TBP), and ethylenediaminetetraacetic acid (EDTA). In addition, examples of organic compounds that can be used in the first impurity removal step S14 and are commercially available include UTEVA (registered trademark) resin from eichrom technologies.

[0038] TOPO is Al, Au, Co, Cr, Fe, Hf, Re, Ti, UO2 2+ , V, Zr, rare earth elements, and actinide elements. D2EHPA can adsorb U, Co, Ni, Mn, etc. TBP can adsorb U, Th, etc. EDTA and the like can adsorb Mg, Ca, Ba, Cu, Zn, Al, Mn, Fe, etc. UTEVA (registered trademark) resin can adsorb U, Th, Pu, Am, etc. These elements are examples of the first element.

[0039] These organic compounds are dissolved in organic solvents (such as kerosene, cyclohexane, benzene, etc.). The organic compounds adsorb the first element by mixing the solution in which these organic compounds are dissolved into the HCl solution after the main heating step S13 and stirring the mixture.

[0040] In the first impurity removal step S14, the HCl solution mixed with the organic compound solution is preferably acidic, and more preferably has a pH of 2 or less. This configuration makes it possible to increase the efficiency with which the organic compound adsorbs the first element without the organic compound adsorbing beryllium. Note that the closer the acidity of the HCl solution is to neutral, the higher the efficiency with which the organic compound adsorbs beryllium and the lower the efficiency with which the organic compound adsorbs the first element.

[0041] In this embodiment, TOPO and kerosene are used as the organic compound and the organic solvent used in the first impurity removal step S14. However, the organic compound and the organic solvent are not limited to TOPO and kerosene, and can be appropriately selected from the combinations exemplified above.

[0042] The aqueous BeCl2 solution obtained by the main heating step S13 and the organic solvent are separated into two layers by leaving them for a while. Therefore, the BeCl2 solution in which the content of the first element is suppressed by carrying out the first impurity removal step S14 can be easily separated from the organic solvent containing the first element.

[0043] By carrying out the first impurity removal step S14, the concentration of the first element contained in the beryllium solution can be reduced. As a result, when a beryllium solution is produced by dissolving beryllium ore in an acidic solution, even if the beryllium ore contains a first element other than beryllium as described above, the concentration of the first element contained in the beryllium solution when producing any of beryllium, beryllium hydroxide, and beryllium oxide from the beryllium solution can be reduced. Examples of the first element include uranium, thorium, plutonium, and americium.

[0044] (Second impurity removal step S15) The second impurity removal step S15 is a step performed after the main heating step S13, and further includes a step of removing the second element from the BeCl2 solution by adjusting the polarity of the BeCl2 solution obtained by the main heating step S13 from acidic to neutral to basic. Note that, in this embodiment, the first impurity removal step S14 and the second impurity removal step S15 are described as being performed in this order after the main heating step S13, but the order of the first impurity removal step S14 and the second impurity removal step S15 can be reversed.

[0045] In this embodiment, the second impurity removal step S15 adds sodium bicarbonate (NaHCO3) to the beryllium solution (HCl solution containing beryllium) after the main heating step S13 is performed until it is saturated. As a result, after the beryllium solution becomes neutral (pH 7), elements other than beryllium (e.g., Al, Fe, etc.) become hydroxides (e.g., Al(OH)3, Fe(OH)3, etc.) and precipitate in the beryllium solution. Even if the sodium bicarbonate is saturated, Be(OH)2 is dissolved in the beryllium solution and does not precipitate. Thus, aluminum (Al) and iron (Fe) are examples of the second element.

[0046] The hydroxides of elements other than beryllium that have precipitated in the beryllium solution by carrying out the second impurity removal step S15 can be easily removed from the beryllium solution by filtering the beryllium solution.

[0047] It is preferable to add HCl again to the beryllium solution from which the second element has been removed by carrying out the second impurity removal step S15. In this way, by adding HCl again to the beryllium solution, the polarity of the Be(OH)2 solution is adjusted from neutral to acidic, and high-purity beryllium chloride hydrate (BeCl2·xH2O) is generated in the solution.

[0048] In this way, by carrying out the second impurity removal step S15, the concentration of the second element contained in the beryllium solution can be reduced. As a result, when a beryllium solution is produced by dissolving beryllium ore in an acidic solution, even if the beryllium ore contains a second element other than beryllium as described above, the concentration of the second element contained in the beryllium solution can be reduced when any of beryllium, beryllium hydroxide, and beryllium oxide is produced using the beryllium solution.

[0049] As described above, in manufacturing method M10, it is preferable that the preliminary heating step S12 dielectrically heats the basic solution containing beryllium oxide by applying microwaves, and the main heating step S13 dielectrically heats the acidic solution containing beryllium oxide by applying microwaves.

[0050] The technology of dielectric heating using microwaves (i.e., microwave dielectric heating) is a technology used in so-called microwave ovens and is a widely used technology. Therefore, the manufacturing method M10 can reduce the cost required for implementation compared to conventional manufacturing methods.

[0051] As mentioned above, in manufacturing method M10, the beryllium solution is preferably a beryllium chloride solution.

[0052] According to the manufacturing method M10, a beryllium chloride solution can be easily manufactured without going through beryllium hydroxide. As described later, beryllium, beryllium hydroxide, and beryllium oxide can be easily manufactured from the beryllium chloride solution. Therefore, a beryllium chloride solution is preferable as the beryllium solution.

[0053] Second to Fourth Embodiments A method for producing beryllium (Be) M20, a method for producing beryllium hydroxide (Be(OH)2) M30, and a method for producing beryllium oxide (BeO) M40 according to second to fourth embodiments of the present invention will be described with reference to (a) to (c) of FIG. 2. (a) to (c) of FIG. 2 are flow charts showing the main parts of the method for producing beryllium M20, the method for producing beryllium hydroxide M30, and the method for producing beryllium oxide M40, respectively. In the following, the method for producing beryllium M20, the method for producing beryllium hydroxide M30, and the method for producing beryllium oxide M40 will also be simply referred to as the production method M20, the production method M30, and the production method M40, respectively.

[0054] (Beryllium manufacturing method M20) As shown in Fig. 2, the manufacturing method M20 includes a pulverization step S11, a preheating step S12, a main heating step S13, a first impurity removal step S14, a second impurity removal step S15, a dehydration step S21, and an electrolysis step S22, which are included in the manufacturing method M10 shown in Fig. 1. Hereinafter, the pulverization step S11, the preheating step S12, the main heating step S13, the first impurity removal step S14, and the second impurity removal step S15 will also be simply referred to as the respective steps S11 to S15.

[0055] The steps S11 to S15 of the manufacturing method M10 included in the manufacturing method M20 are the same as the steps S11 to S15 described in the first embodiment. Therefore, the description of the steps S11 to S15 will be omitted here. In other words, assuming that a BeCl2 solution in which BeCl2 is dissolved in an HCl solution is obtained, only the dehydration step S21 and the electrolysis step S22 of the manufacturing method M20 will be described.

[0056] The dehydration step S21 is a step for producing BeCl2, which is an example of a beryllium salt, by dehydrating BeCl2·xH2O contained in the BeCl2 solution obtained in each of steps S11 to S15 of the manufacturing method M10.

[0057] 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 making the water content as close to 0 as possible. In other words, the beryllium chloride hydrate can be dehydrated.

[0058] Ammonium chloride reacts with the water in the beryllium chloride hydrate to form ammonium hydroxide and hydrochloric acid. The ammonium hydroxide and hydrochloric acid produced react again to return to ammonium chloride while releasing water. In this process, anhydrous beryllium chloride can be obtained from the beryllium chloride hydrate.

[0059] The heating temperature in the dehydration step S21 is not limited to 90°C, and 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 the beryllium chloride hydrate is likely to be insufficient. Therefore, the heating temperature is preferably 80°C to 90°C, and more preferably 90°C.

[0060] The time period for which the dehydration process is carried out in the dehydration step S21 is not limited to 24 hours, but can be determined as appropriate.

[0061] The electrolysis step S22 is a step of producing metallic beryllium by subjecting the BeCl2 obtained in the dehydration step S21 to molten salt electrolysis.

[0062] As described above, by carrying out manufacturing method M20, metallic beryllium can be produced from beryllium ore via a BeCl2 solution. In other words, by carrying out manufacturing method M20, beryllium can be produced from beryllium ore without going through beryllium hydroxide. In the currently commercialized manufacturing method for producing beryllium from beryllium ore, beryllium hydroxide, which is in high demand in general, is produced from beryllium ore, and then beryllium is produced from the beryllium hydroxide. Therefore, manufacturing method M20 can produce beryllium more easily than the currently commercialized manufacturing method for beryllium.

[0063] (Beryllium hydroxide manufacturing method M30) 2, production method M30 includes steps S11 to S15 of production method M10 and a neutralization step S31. As in the case of production method M20, only the neutralization step S31 will be described here.

[0064] The neutralization step S31 is a step in which BeCl2·xH2O contained in the BeCl2 solution obtained in each of steps S11 to S15 of the production method M10 is neutralized with a base to produce Be(OH)2.

[0065] As described above, by carrying out the production method M30, Be(OH)2 can be produced from beryllium ore.

[0066] (Beryllium oxide manufacturing method M40) 2, manufacturing method M40 includes steps S11 to S15 of manufacturing method M10 and a heating step S41. As in the case of manufacturing method M20, only the heating step S41 will be described here.

[0067] The heating step S41 includes a third heating step of generating BeO by heating the BeCl2 solution obtained by each of steps S11 to S15 of the manufacturing method M10. By this step, BeCl2·xH2O dissolved in the BeCl2 solution is hydrolyzed to generate BeO.

[0068] As described above, by carrying out the manufacturing method M40, BeO can be produced from beryllium ore.

[0069] (summary) According to each of these manufacturing methods M20, M30, and M40, beryllium, beryllium hydroxide, and beryllium oxide can be produced using a novel manufacturing method with high energy efficiency. Note that each of the dehydration step S21, the electrolysis step S22, the neutralization step S31, and the heating step S41 can be performed by utilizing existing technology.

[0070] Fifth embodiment A heating device 10 according to a fifth embodiment of the present invention will be described with reference to Fig. 3. Fig. 3 is a schematic diagram of the heating device 10. The heating device 10 is a heating device that performs each of the preliminary heating step S12 and the main heating step S13 included in the manufacturing method M10 shown in Fig. 1.

[0071] As described in the first embodiment, induction heating is classified into either high-frequency heating or microwave heating depending on the band of electromagnetic waves applied. The heating device 10 is a device that performs microwave heating, out of high-frequency heating and microwave heating, on an object.

[0072] 3, the heating device 10 includes a microwave oscillator 11, a waveguide 12, a microwave applicator 13, a container 14, a rotating table 15, a stirrer 16, and a thermometer 17. The heating device 10 further includes a control unit not shown in FIG.

[0073] The microwave oscillator 11 is configured to oscillate electromagnetic waves having a predetermined frequency. The predetermined frequency can be appropriately selected within the microwave band, for example, but in this embodiment, the predetermined frequency is 2.45 GHz. The frequency of 2.45 GHz is the same frequency as that of electromagnetic waves used in home microwave ovens.

[0074] Waveguide 12 is a metallic cylindrical member, one end of which is connected to microwave oscillator 11 and the other end of which is connected to microwave application unit 13. Waveguide 12 guides the electromagnetic waves oscillated by microwave oscillator 11 from one end to the other end, and radiates the electromagnetic waves from the other end into the internal space of microwave application unit 13.

[0075] The microwave application unit 13 is a metal box-shaped member with a hollow internal space, and is configured to be able to accommodate the container 14 in the internal space. The microwave 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 accommodated in the container 14. The microwave application unit 13 is configured to confine the electromagnetic waves in the internal space and to prevent them from leaking to the outside.

[0076] Although not shown in Fig. 3, container 14 is a container composed of a main body and a lid. The main body is composed of a cylindrical side wall and a bottom that seals one end of the side wall. Container 14 is configured so that the internal space formed by the main body and the lid can be sealed by joining the main body and the lid.

[0077] The container 14 is preferably made of a material having high transmittance to the electromagnetic wave (2.45 GHz in this embodiment) oscillated by the microwave oscillator 11. In this embodiment, the container 14 is made of a fluorine-based resin such as polytetrafluoroethylene.

[0078] In addition, it is preferable that the container 14 has a pressure resistance that can withstand even when the pressure in the internal space becomes higher than atmospheric pressure. By being able to seal the internal space and having a pressure resistance that can withstand a predetermined pressure, the container 14 can keep the object to be heated contained in the internal space even when electromagnetic waves are applied and the temperature of the object to be heated contained in the internal space rises.

[0079] The turntable 15 is a sample stage provided on the bottom surface of the internal space of the microwave application unit 13, and is configured so that the container 14 can be placed on the upper surface. The turntable 15 has a circular shape when viewed from above, and is configured to rotate at a predetermined speed with its central axis as the rotation axis. With this configuration, the container 14 placed on the upper surface of the turntable 15 rotates periodically, so that the target object can be heated more uniformly.

[0080] The stirrer 16 is a metallic vane-shaped member provided on the ceiling surface of the internal space of the microwave application unit 13. 、 The stirrer 16 is fixed to the ceiling surface in a freely rotatable state by a support rod connected to the center of the feather-shaped member. The stirrer 16 rotates at a predetermined speed with the support rod as the axis of rotation, thereby reflecting the electromagnetic waves generated by the microwave oscillator 11 and scattering them in the internal space of the microwave applicator 13. With this configuration, the stirrer 16 scatters the electromagnetic waves, so that the target object can be heated more uniformly.

[0081] The thermometer 17 is a radiation thermometer that measures the temperature of the container 14 by detecting infrared rays emitted by the container 14. The temperature of the container 14 becomes approximately the same as the temperature of the object contained in the internal space of the container 14 after a predetermined temperature relaxation time has passed. This temperature relaxation time depends on the material (fluorine-based resin in this embodiment) constituting the container 14 and its thickness (for example, 1 mm). In the case of the container 14 made of fluorine-based resin and having a thickness of 1 mm as in this embodiment, the temperature relaxation time is expected to be approximately 3 minutes. Therefore, when the heating time is sufficiently long compared to the temperature relaxation time and / or when the temperature change of the object contained in the internal space of the container 14 is sufficiently gradual, the temperature of the object contained in the internal space of the container 14 and the temperature of the container 14 can be considered to be the same. Therefore, in such a case, the thermometer 17 can be considered to be capable of measuring the temperature of the object. The thermometer 17 outputs a temperature signal indicating the measured temperature of the container 14 or the object to the control unit.

[0082] The control unit may control the output of the microwave oscillator 11 so that the output becomes a predetermined value, or may control the output of the microwave oscillator 11 so that the temperature of the temperature signal received from the thermometer 17 becomes 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 microwave oscillator 11 so that the output value changes over time. An example of the output value that changes over time is a pattern in which the output is changed from 0 W to 600 W over 30 minutes, and then 600 W is maintained for 60 minutes.

[0083] Using the heating device 10 thus configured, the preliminary heating step S12 can be carried out by storing the beryl crushed in the crushing step S11 and a basic solution in the internal space of the container 14. Similarly, using the heating device 10, the main heating step S13 can be carried out by storing the beryl after the preliminary heating step S12 and an acidic solution in the internal space of the container 14.

[0084] [Experimental Results] FIG. 4 is a table summarizing the experimental conditions of Experiments 1 to 6 including the examples of the present invention and the comparative examples. FIG. 5 is a graph showing the temperature change of the container in the main heating step S13 included in one embodiment of the present invention. FIG. 6 is a microscope image of beryl before and after the preliminary heating step S12 in one embodiment of the present invention. FIG. 7 is a table summarizing the amounts of dissolved Be, Al, and Si in Experiments 1 to 6 shown in FIG. 4. FIG. 8 is a table summarizing the experimental results of Experiments 1 to 6 shown in FIG. 4. Incidentally, phenacite, which is an example of a Be-Si-O ore, contains almost no Al. Therefore, it is considered that the amount of dissolved Al included in the phenacite column shown in FIG. 7 is due to a small amount of Al contained as an impurity in phenacite.

[0085] As shown in FIG. 4, experiments 1 and 2 were carried out in which beryllium ore was treated with a basic solution, experiments 3 and 4 in which beryllium ore was treated with an acidic solution, and experiments 5 and 6 in which beryllium ore was treated with a basic solution and then with an acidic solution, and the extent to which beryllium ions contained in the beryllium ore were dissolved in the solution was examined. In other words, experiment 2 was carried out only in the preliminary heating step S12 shown in FIG. 1, experiment 4 was carried out only in the main heating step S13 shown in FIG. 1, and experiment 6 was carried out in which the preliminary heating step S12 shown in FIG. 1 was carried out and then the main heating step S13 was carried out. Moreover, each of experiments 1, 3, and 5 corresponds to experiments 2, 4, and 6, respectively, and each solution was left at room temperature (RT) without microwave heating. In each of FIG. 4, FIG. 7, and FIG. 8, the subscript (MW) is added to the experiments in which microwave heating was carried out, and the subscript (RT) is added to the experiments in which microwave heating was not carried out.

[0086] In each of Experiments 2, 4, and 6, the output value of the heating device 10 was changed over time. Specifically, the output value was increased from 0 W to 600 W over 30 minutes, and then the output value was maintained at 600 W for 60 minutes, after which the output value was quickly decreased to 0 W.

[0087] When the output value of the microwave oscillator 11 was changed according to the above-mentioned pattern, the temperature of the container 14 continued to rise even after the output value reached 600 W, and the maximum temperature reached was approximately 220° C., as shown in Fig. 5. This temperature change in the container 14 was common to the pre-heating step S12 of Experiment 2, the main heating step S13 of Experiment 4, and the pre-heating step S12 and main heating step S13 of Experiment 6.

[0088] In experiments 1 and 2, the solutes of the basic solution were NH3, NaOH, and KOH. In experiments 3 and 4, the solutes of the acidic solution were HCl, H2SO4, and HNO3. In experiments 5 and 6, the solutes of the basic solution were NaOH and KOH, and the solutes of the acidic solution were HCl, H2SO4, and HNO3.

[0089] In each of Experiments 1 to 6, beryl, chrysoberyl, phenacite, and bertrandite were used as the raw material beryllium ore.

[0090] Referring to FIG. 6, in Experiment 6, in which beryl was used as the raw material, NaOH was used as the solute of the basic solution, and HCl was used as the solute of the acidic solution, it was found that by carrying out the pre-heating step S12, multiple recesses were formed on the surface of the beryl that did not exist before carrying out the pre-heating step S12. Furthermore, it was found that among these multiple recesses, the recesses excluding the recesses that existed before carrying out the pre-heating step S12 have an opening shape that reflects the shape of the unit lattice of the crystal (rectangular shape). It was also found that the surface roughness Ra of the beryl was roughened from 0.93 μm to 21.48 μm by carrying out the pre-heating step S12. The beryl was a lump with a grain size of about 7 mm, and one surface of the surface was polished.

[0091] In this way, it was found that by carrying out the pre-heating step S12 in beryl, which is an example of a Be-Si-Al-O ore, the surface can be etched, i.e., the surface structure can be corroded, dissolved, collapsed, etc.

[0092] Figure 7 shows some of the results of Experiments 1 to 6. The amounts of Be, Al, and Si dissolved in the solution were analyzed using an inductively coupled plasma mass spectrometer (ICP-MS). The dissolved amounts shown in Figure 7 indicate the ratio of the amount of each dissolved element to the total amount of the ore. In other words, when an element contained in an ore is completely dissolved, its solubility is equal to the ratio of that element in the ore.

[0093] The results of Experiment 1 showed that treatment with a basic solution alone, without microwave heating, was not able to sufficiently dissolve beryllium in any of the beryllium ores.

[0094] The results of Experiment 2 showed that when microwave heating and treatment with a basic solution were used in combination, beryllium was dissolved in all beryllium ores, but the dissolution was not sufficient.

[0095] The results of Experiment 3 showed that treatment with an acidic solution alone, without microwave heating, was not able to sufficiently dissolve beryllium in any of the beryllium ores.

[0096] The results of Experiment 4 show that when microwave heating and treatment using an acidic solution were used in combination (i.e., when only the main heating step S13 was performed), beryllium could not be sufficiently dissolved in beryl containing Al, but beryllium could be sufficiently dissolved in phenasite not containing Al.

[0097] The results of Experiment 5 showed that when treatment with a basic solution without microwave heating was followed by treatment with an acidic solution without microwave heating, beryllium could not be sufficiently dissolved in any of the beryllium ores.

[0098] The results of Experiment 6 show that when microwave heating and treatment with a basic solution were used in combination, and then microwave heating and treatment with an acidic solution were used in combination (i.e., when the main heating step S13 was performed after the preliminary heating step S12), beryllium could be sufficiently dissolved even in beryl containing Al.

[0099] Regarding Experiment 6, the results for phenacite, which does not contain Al, are not shown in FIG. 7, but phenacite also successfully dissolved beryllium.

[0100] In addition, in the experiment 6, the polarity of the solution containing beryllium ore was adjusted from basic to acidic in the process of transition from the preliminary heating step S12 to the main heating step S13. At that time, a compound containing Si could be precipitated in the acidic solution, and as a result, Si could be removed from the solution. The precipitation of the compound containing Si is considered to be caused by Na2SiO3 dissolved in the basic solution changing to H2SiO3 in the acidic solution and precipitating, as shown in the following chemical formula. Note that Na2SiO3 is soluble in water, and H2SiO3 is not soluble in the acidic solution. Pre-heating process S12: SiO2+2NaOH→Na2SiO3+H2O Main heating step S13: Na2SiO3+2HCl→H2SiO3↓+2NaCl The results of Experiments 1 to 6 are summarized in Figure 8. In Figure 8, a cross, a triangle, a circle, and a double circle indicate that beryllium was not dissolved, slightly dissolved, almost dissolved, and completely dissolved, respectively. The cross, triangle, circle, and double circle in each of Experiments 1 to 6 were determined based on a combination of the analysis results using an ICP mass spectrometer and the results of visually inspecting the state of the solution after each experiment.

[0101] Referring to FIG. 8, when the raw material is beryl or chrysoberyl, it is found that beryllium can be sufficiently dissolved by carrying out a pre-heating step S12 using NaOH or KOH as the solute of the basic solution, followed by a main heating step S13 using any one of HCl, H2SO4, and HNO3 as the solute of the acidic solution.

[0102] In addition, when the raw materials are phenacite and bertrandite, it has been found that beryllium can be sufficiently dissolved by carrying out a preliminary heating step S12 in which NaOH or KOH is used as the solute of the basic solution, followed by a main heating step S13 in which any of HCl, H2SO4, and HNO3 is used as the solute of the acidic solution.

[0103] In addition, it was found that when the raw materials were phenacite and bertrandite, beryllium could be sufficiently dissolved by only carrying out the main heating step S13 in which HCl or H2SO4 was used as the solute of the acidic solution.

[0104] FIG. 9 is a graph showing the correlation between the maximum temperature of the acid solution and the solubility of beryllium when the main heating step S13 was performed for the phenasite of Experiment 4 and the beryl of Experiment 6 shown in FIG.

[0105] Of the three beryls B1 to B3 and phenasite P1 to P3 plotted in Fig. 9, beryl B1 is a sample in which the output value of the microwave oscillator 11 was increased from 0 W to 300 W over 30 minutes in both the preliminary heating step S12 and the main heating step S13, the output value was then maintained at 300 W for 60 minutes, and the output value was then rapidly reduced to 0 W. Phenasite P1 is a sample in which the output value of the microwave oscillator 11 was increased from 0 W to 300 W over 30 minutes in the main heating step S13, the output value was then maintained at 300 W for 60 minutes, and the output value was then rapidly reduced to 0 W. Beryl B2 is obtained by increasing the output value of the microwave oscillator 11 from 0 W to 600 W over 30 minutes in both the preheating step S12 and the main heating step S13, then maintaining the output value at 600 W for 60 minutes, and then quickly lowering the output value to 0 W. Phenacite P2 is obtained by increasing the output value of the microwave oscillator 11 from 0 W to 600 W over 30 minutes in the main heating step S13, then maintaining the output value at 600 W for 60 minutes, and then quickly lowering the output value to 0 W. Beryl B3 is obtained by not performing the preheating step S12 and the main heating step S13, and leaving the beryl in a basic solution for 60 minutes at room temperature (RT = 25 ° C.) and then leaving it in an acidic solution for 60 minutes. For Phenacite P3, the preliminary heating step S12 and the main heating step S13 were not carried out, and Phenacite was left in the acidic solution at room temperature (RT=25° C.) for 60 minutes.

[0106] In the case of Phenasite P1 and Beryl B1, the maximum temperatures during the main heating step S13 were 180° C. and 190° C., respectively. In the case of Phenasite P2 and Beryl B2, the maximum temperatures during the main heating step S13 were both 250° C. In the case of Beryl B1 and Beryl B2, the maximum temperatures during the pre-heating step S12 were approximately the same as the maximum temperatures during the main heating step S13, although not shown in the figures.

[0107] 9, it was found that in Beryl B3 and Phenacite P3, most of the beryl and phenacite remained, and the beryllium contained in the beryl and phenacite was hardly dissolved as beryllium ions.On the other hand, it was found that (1) in Phenacite P1, 60% of the beryllium was dissolved as beryllium ions, (2) in Beryl B1, 50% of the beryllium was dissolved as beryllium ions, and (3) in Phenacite P2 and Beryl B2, almost 100% of the beryllium was dissolved as beryllium ions.

[0108] [Results of additional experiments] In the above-mentioned experiments 1 to 6, the ratio of the amount of each element dissolved to the whole ore was calculated as the dissolved amount of each element (see FIG. 7). Then, the analysis results by the ICP mass spectrometer and the results of visually checking the state of the solution after each experiment were combined to determine the degree of dissolution of each element as either a cross, a triangle, a circle, or a double circle (see FIG. 8). As mentioned above, Al in phenacite is considered to be derived from impurities. Therefore, the solubility of Al in phenacite is omitted in FIG. 10(a).

[0109] In the additional experiment described below, the above-mentioned experiments 1 to 6 were performed again, the amount of each element dissolved in the HCl solution was analyzed using an ICP mass spectrometer, and the ratio of the amount of each dissolved element to the amount of each element contained in the ore was calculated as the solubility. In other words, when an element contained in the ore is completely dissolved, its solubility is 100%.

[0110] The solubilities calculated in this manner are shown in (a) of Figure 10. The composition ratio of Be, Al, and Si in the beryl used in Experiments 1 to 6 was 3.1:6.3:20.0, and the composition ratio of Be and Si in the phenacite was 15.2:22.0 (see (b) of Figure 10).

[0111] Then, (1) if the solubility was 10% or less, it was judged as insoluble (i.e., a cross), (2) if the solubility was more than 10% and less than 50%, it was judged as slightly dissolved (i.e., a triangle), (3) if the solubility was more than 50% and less than 100%, it was judged as almost dissolved (i.e., a circle), and (4) if the solubility was 100%, it was judged as completely dissolved (i.e., a double circle). The judgment results obtained in this way are shown in Figure 11.

[0112] The results of Experiment 1 of the additional experiment showed that treatment with a basic solution alone, without microwave heating, was not able to dissolve beryllium in any of the beryllium ores.

[0113] The results of an additional experiment, Experiment 2, showed that when microwave heating was combined with treatment with a basic solution, beryllium was dissolved slightly in all beryllium ores, but the dissolution was not sufficient.

[0114] The results of Experiment 3, an additional experiment, showed that treatment with an acidic solution alone, without microwave heating, did not dissolve the beryllium in any of the beryllium ores, or did not dissolve it sufficiently.

[0115] The results of Experiment 4 of the additional experiment showed that when microwave heating and treatment using an acidic solution were used in combination (i.e., when only the main heating step S13 was performed), beryllium could not be sufficiently dissolved in beryl containing Al, but beryllium could be sufficiently dissolved in phenasite, which does not contain Al.

[0116] The results of Experiment 5, an additional experiment, showed that when treatment with a basic solution without microwave heating was followed by treatment with an acidic solution without microwave heating, beryllium was not sufficiently dissolved in any of the beryllium ores.

[0117] The results of Experiment 6 of the additional experiment showed that when microwave heating and treatment with a basic solution were used in combination, and then microwave heating and treatment with an acidic solution were used in combination (i.e., when the main heating step S13 was performed after the preliminary heating step S12), beryllium could be sufficiently dissolved even in beryl containing Al.

[0118] As described above, the results of Experiments 1 to 6 of the additional experiments (see FIGS. 10 and 11) were consistent with the results of Experiments 1 to 6 (see FIGS. 7 and 8).

[0119] [Experiment on the first impurity removal process] In the manufacturing method M10 shown in Fig. 1, the pH of the HCl solution after the main heating step S13 was changed, and the first impurity removal step S14 was then performed, and the concentrations of beryllium and uranium remaining in the HCl solution were measured. In this experiment, tri-n-octylphosphine oxide (TOPO) was used as the organic compound, and kerosene was used as the organic solvent. That is, TOPO was dissolved in kerosene.

[0120] In this example, after carrying out the main heating step S13, a number of HCl solutions with pH values ​​varying from 1 to 7 were prepared, and kerosene with TOPO dissolved therein was mixed and stirred with each HCl solution, and the mixture was left to stand for a while. As a result, the HCl solution mixed with kerosene with TOPO dissolved therein separated into two layers. After separating this solution into an aqueous layer and an organic layer, the concentrations of beryllium and uranium in the aqueous layer were measured.

[0121] In the HCl solution having a pH of 7 after the main heating step S13, when the impurity removal step S14 was performed, the extraction of uranium into the organic layer was insufficient, and about half of the uranium remained in the aqueous layer of the HCl solution. Furthermore, in this HCl solution, about 80% of the beryllium was extracted into the organic layer. Therefore, it was found that it is not preferable to perform the impurity removal step S14 when the pH of the HCl solution after the main heating step S13 is 7.

[0122] On the other hand, in the case of an HCl solution whose pH was 2 or less after the main heating step S13 was performed, when the impurity removal step S14 was performed, uranium was completely extracted into the organic layer, and beryllium was not extracted into the organic layer. From this, it was found that the pH of the HCl solution when the first impurity removal step S14 is performed (i.e., the HCl solution after the main heating step S13 is performed) is preferably 2 or less.

[0123] [Experiment on the dehydration process] The dehydration step S21 of the manufacturing method M20 shown in Fig. 2(a) was carried out. In this experiment, ammonium chloride was added to beryllium chloride hydrate, and the beryllium chloride hydrate was heated in a vacuum at 90°C for 24 hours. As a result, it was found that the water content in the beryllium chloride could be brought as close to zero as possible, that is, the beryllium chloride hydrate could be dehydrated.

[0124] 〔summary〕 In order to solve the above problems, a method for producing a beryllium solution according to a first aspect of the present invention includes a main heating step of producing a beryllium solution by dielectrically heating an acidic solution containing beryllium oxide.

[0125] By using dielectric heating to heat the acidic solution containing beryllium oxide, it is possible to dissolve beryllium oxide in the acidic solution with higher energy efficiency than in the past, and therefore the present production method can provide a novel production method with high energy efficiency.

[0126] A second aspect of the present invention relates to a method for producing a beryllium solution according to the first aspect, and further includes a preheating step carried out before the main heating step, in which the basic solution containing beryllium oxide is dielectrically heated.

[0127] By carrying out the pre-heating step before carrying out the main heating step, it is possible to dissolve beryllium oxides that are difficult to dissolve by carrying out the main heating step alone, and therefore it is possible to produce a beryllium solution using a wider range of beryllium oxides as the starting material.

[0128] A third aspect of the present invention relates to a method for producing a beryllium solution, and is based on the first or second aspect above, and further includes a first impurity removal step carried out after the main heating step, in which an organic compound that adsorbs a first element is used to remove the first element from the beryllium solution obtained by the main heating step.

[0129] By carrying out the first impurity removal step, the concentration of the first element contained in the beryllium solution can be reduced. As a result, the concentration of the first element contained in the beryllium solution can be reduced when any one of beryllium, beryllium hydroxide, and beryllium oxide is produced using the beryllium solution. Examples of the first element include uranium, thorium, plutonium, and americium.

[0130] A fourth aspect of the present invention relates to a method for producing a beryllium solution according to the third aspect, wherein in the first impurity removal step, the organic compound is dissolved in an organic solvent and the beryllium solution is acidic.

[0131] According to this configuration, it is possible to increase the efficiency with which the organic compound adsorbs the first element.

[0132] A method for producing a beryllium solution according to a fifth aspect of the present invention is, in any one of the first to fourth aspects, further comprising a second impurity removal step carried out after the main heating step, in which the polarity of the beryllium solution obtained by the main heating step is adjusted from acidic to basic, thereby removing a second element from the beryllium solution.

[0133] By carrying out the second impurity removal step, the concentration of the second element contained in the beryllium solution can be reduced. As a result, the concentration of the second element contained in the beryllium solution can be reduced when any one of beryllium, beryllium hydroxide, and beryllium oxide is produced using the beryllium solution. Examples of the second element include aluminum and iron.

[0134] A sixth aspect of the present invention relates to a method for producing a beryllium solution according to any one of the first to fifth aspects, wherein the main heating step comprises applying microwaves to dielectrically heat the acidic solution containing the beryllium oxide.

[0135] The technology of dielectric heating using microwaves (i.e., microwave dielectric heating) is a technology used in so-called microwave ovens and is a widely used technology. Therefore, the production method of the present invention can reduce the cost required for implementation compared to conventional production methods.

[0136] A seventh aspect of the present invention provides a method for producing a beryllium solution, wherein in any one of the first to sixth aspects, the beryllium solution is a beryllium chloride solution.

[0137] According to this manufacturing method, a beryllium chloride solution can be easily manufactured without going through beryllium hydroxide. As described later, beryllium, beryllium hydroxide, and beryllium oxide can be easily manufactured from the beryllium chloride solution. Therefore, a beryllium chloride solution is preferable as the beryllium solution.

[0138] A method for producing beryllium according to an eighth aspect of the present invention includes each of the steps included in the method for producing a beryllium solution according to any of the first to sixth aspects, as well as a dehydration step of producing a beryllium salt by dehydrating the beryllium solution, and an electrolysis step of producing beryllium by subjecting the beryllium salt to molten salt electrolysis.

[0139] A method for producing beryllium hydroxide according to a tenth aspect of the present invention includes each step included in the method for producing a beryllium solution according to any one of the first to sixth aspects, and a neutralization step of producing beryllium hydroxide by neutralizing the beryllium solution with a base.

[0140] A method for producing beryllium oxide according to an eleventh aspect of the present invention includes each step included in the method for producing a beryllium solution according to any one of the first to sixth aspects, and a third heating step of producing beryllium oxide by heating the beryllium solution.

[0141] According to these manufacturing methods, beryllium, beryllium hydroxide, and beryllium oxide can be manufactured using a novel manufacturing method with high energy efficiency. In addition, the manufacturing method for beryllium according to the seventh aspect can manufacture metallic beryllium from a beryllium solution manufactured by the manufacturing method for a beryllium solution according to one aspect of the present invention, without going through beryllium hydroxide. In a manufacturing method for manufacturing beryllium from beryllium ore that is currently commercially available, beryllium hydroxide, which is in high demand in general, is manufactured from the beryllium ore, and then beryllium is manufactured from the beryllium hydroxide. Therefore, the manufacturing method for beryllium according to the seventh aspect can manufacture beryllium more easily than the manufacturing method for beryllium that is currently commercially available.

[0142] A ninth aspect of the present invention relates to a method for producing beryllium according to the eighth aspect, wherein the beryllium solution is a beryllium chloride solution, and the dehydration step is configured to heat the beryllium chloride hydrate contained in the beryllium chloride solution in a vacuum at a temperature of 80°C or higher and 110°C or lower.

[0143] According to this configuration, when the beryllium solution is a beryllium chloride solution, the beryllium chloride hydrate can be reliably subjected to the dehydration treatment.

[0144] A twelfth aspect of the present invention provides a beryllium oxide having crystallinity and a plurality of recesses formed on its surface, wherein some or all of the plurality of recesses have openings with shapes that reflect the shape of the unit lattice of the crystal.

[0145] The beryllium oxide according to the present invention has a surface on which a plurality of recesses are formed, the openings of which have a shape that reflects the shape of the unit lattice of the crystal, and is therefore easily dissolved in an acidic solution by being dielectrically heated in the acidic solution. Therefore, the beryllium oxide according to one embodiment of the present invention is suitable as a raw material for producing a beryllium solution.

[0146] The beryllium oxide according to a thirteenth aspect of the present invention is the beryllium oxide according to the twelfth aspect, further comprising silicon and aluminum.

[0147] Beryllium oxide containing silicon and aluminum is difficult to dissolve even when it is subjected to dielectric heating in an acidic solution, but by forming a plurality of recesses on the surface, the beryllium oxide containing silicon and aluminum can be easily dissolved by dielectric heating in an acidic solution.

[0148] Note that a beryllium solution containing the beryllium oxide according to the twelfth and thirteenth aspects and beryllium ions is also one aspect of the present invention.

[0149] [Additional Notes] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. [Explanation of symbols]

[0150] M10 Manufacturing method (method of manufacturing beryllium solution, method of manufacturing BeCl2 solution) S11 Crushing process S12 Pre-heating process S13 Main heating process S14, S15 First and second impurity removal processes M20, M30, M40: Methods for producing beryllium, beryllium hydroxide, and beryllium oxide S21 Anhydrous process S22 Electrolysis process S31 Neutralization process S41 Heating process

Claims

1. a main heating step of producing a beryllium solution by dielectrically heating an acidic solution containing beryllium oxide; A preheating step performed before the main heating step, in which the basic solution containing the beryllium oxide is dielectrically heated.

2. A method for producing a beryllium solution comprising the steps of:

2. A method for producing a beryllium solution by dielectrically heating an acidic solution containing beryllium oxide, comprising the steps of: The beryllium solution is a beryllium chloride solution.

2. A method for producing a beryllium solution comprising the steps of:

3. A method for producing a beryllium solution by dielectrically heating an acidic solution containing beryllium oxide, comprising: The acidic solution is a HCl solution.

2. A method for producing a beryllium solution comprising the steps of:

4. The method further includes a first impurity removal step carried out after the main heating step, in which the first element is removed from the beryllium solution obtained by the main heating step using an organic compound that adsorbs the first element.

4. The method for producing a beryllium solution according to claim 1, wherein the beryllium solution is a mixture of a beryllium oxide and a beryllium fluoride.

5. In the first impurity removal step, The organic compound is dissolved in an organic solvent, The beryllium solution is acidic.

5. The method for producing a beryllium solution according to claim 4.

6. The method further includes a second impurity removal step carried out after the main heating step, in which the polarity of the beryllium solution obtained by the main heating step is adjusted from acidic to basic, thereby removing a second element from the beryllium solution.

6. The method for producing a beryllium solution according to claim 1,

7. The main heating step comprises applying microwaves to the acidic solution containing the beryllium oxide to perform dielectric heating.

7. The method for producing a beryllium solution according to claim 1,

8. Each step included in the method for producing a beryllium solution according to any one of claims 1 and 3 to 7; a dehydration step of producing a beryllium salt by dehydrating the beryllium solution; and an electrolysis step of producing beryllium by subjecting the beryllium salt to molten salt electrolysis. A method for producing beryllium, comprising:

9. A main heating step of producing a beryllium solution by dielectrically heating an acidic solution containing beryllium oxide; a dehydration step of producing a beryllium salt by dehydrating the beryllium solution; and an electrolysis step of producing beryllium by subjecting the beryllium salt to molten salt electrolysis. A method for producing beryllium, comprising:

10. The beryllium solution is a beryllium chloride solution, The dehydration step comprises heating the beryllium chloride hydrate contained in the beryllium chloride solution in a vacuum at a temperature of 80° C. or higher and 110° C. or lower.

10. The method for producing beryllium according to claim 8 or 9.

11. Each step included in the method for producing a beryllium solution according to any one of claims 1 and 3 to 7; and neutralizing the beryllium solution with a base to produce beryllium hydroxide. A method for producing beryllium hydroxide comprising the steps of:

12. Each step included in the method for producing a beryllium solution according to any one of claims 1 and 3 to 7; and a third heating step of heating the beryllium solution to produce beryllium oxide.

2. A method for producing beryllium oxide comprising the steps of:

13. A method for producing a ...

2. A method for producing beryllium oxide comprising the steps of:

14. A plurality of recesses are formed on the surface of the beryllium oxide obtained by carrying out the preheating step, Some or all of the recesses among the plurality of recesses have opening shapes that reflect the shape of a unit lattice of a crystal. The method for producing beryllium oxide according to claim 13.

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