Inorganic compound particle manufacturing device

Abstract

The present invention provides an inorganic compound particle manufacturing apparatus capable of producing inorganic compound particles with a particle size in the nanometer range. [Solution] The inorganic compound manufacturing apparatus comprises a first raw material supply unit that supplies a first solution and a second solution; a first mixing unit having a first mixer that mixes the first solution and the second solution supplied from the first raw material supply unit; a second raw material supply unit that supplies the first solution and the second solution; and a second mixing unit located downstream of the first mixing unit that mixes the first solution and the second solution supplied from the second raw material supply unit into the mixed solution of the first solution and the second solution.

Description

Technical Field

[0001] The present disclosure relates to an inorganic compound particle manufacturing apparatus using microchannels.

Background Art

[0002] Conventionally, inorganic compound particles have been used in various applications, and in order to obtain inorganic compound particles having a desired particle size according to the application, they have been produced by various manufacturing methods. For example, a crystal manufacturing apparatus including a reaction vessel for crystallizing a crystalline compound, a sedimentation separator for classifying by sedimentation separation into crystals on the large particle size side and crystals on the small particle size side, and a filter for filtering and concentrating is known (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the above crystal manufacturing apparatus, it is difficult to classify particles having a particle size in the order of several μm, and it is substantially limited to particles having a particle size of 10 μm or more, and it was impossible to obtain inorganic compound particles having a smaller particle size in the order of nm.

[0005] Therefore, an object of the present disclosure is to provide an inorganic compound particle manufacturing apparatus capable of manufacturing inorganic compound particles having a particle size in the order of nm.

Means for Solving the Problems

[0006] The inorganic compound manufacturing apparatus according to this disclosure comprises: a first raw material supply unit that supplies a first solution and a second solution; a first mixing unit having a first mixer that mixes the first solution and the second solution supplied from the first raw material supply unit; a second raw material supply unit that supplies the first solution and the second solution; and a second mixing unit located downstream of the first mixing unit that mixes the first solution and the second solution supplied from the second raw material supply unit into a mixed solution of the first solution and the second solution. [Effects of the Invention]

[0007] The inorganic compound particle manufacturing apparatus described herein can produce inorganic compound particles with a particle size in the nanometer range. [Brief explanation of the drawing]

[0008] [Figure 1A] This is a schematic diagram showing the configuration of the inorganic compound particle manufacturing apparatus according to Embodiment 1. [Figure 1B] This is a schematic diagram showing the change in particle size of inorganic compound particles before and after the supply of the additional second solution in the third mixer in Figure 1. [Figure 1C] This is a schematic diagram showing the particle size distribution and particle size control range of inorganic compound particles obtained by the inorganic compound particle manufacturing apparatus according to Embodiment 1. [Figure 2] Table 1 shows the manufacturing conditions for inorganic compound particles and the characteristics of the obtained inorganic compound particles for Examples 1 to 6 and Comparative Examples 1 to 3 using the inorganic compound particle manufacturing apparatus shown in Figure 1A. [Figure 3] This is a schematic diagram showing the configuration of the inorganic compound particle manufacturing apparatus according to Embodiment 2. [Figure 4] Table 2 shows the manufacturing conditions for inorganic compound particles and the characteristics of the obtained inorganic compound particles for Examples 7 to 10 and Comparative Examples 4 to 5, using the inorganic compound particle manufacturing apparatus shown in Figure 3. [Modes for carrying out the invention]

[0009] An inorganic compound manufacturing apparatus according to the first embodiment comprises: a first raw material supply unit that supplies a first solution and a second solution; a first mixing unit having a first mixer that mixes the first solution and the second solution supplied from the first raw material supply unit; a second raw material supply unit that supplies the first solution and the second solution; and a second mixing unit located downstream of the first mixing unit that mixes the first solution and the second solution supplied from the second raw material supply unit into a mixed solution of the first solution and the second solution.

[0010] In the inorganic compound manufacturing apparatus according to the second embodiment, the second raw material supply unit may supply the first solution and the second solution separately to the second mixing unit, as described in the first embodiment.

[0011] In the third embodiment of the inorganic compound manufacturing apparatus, the second mixing section may include a second mixer downstream of the first mixing section for mixing a first solution from a second raw material supply section, and a third mixer downstream of the second mixer for mixing a second solution from a second raw material supply section.

[0012] In the inorganic compound manufacturing apparatus according to the fourth embodiment, the second raw material supply unit may supply a mixed solution obtained by mixing the first solution and the second solution to the second mixing unit so that the concentration is below saturation.

[0013] The inorganic compound manufacturing apparatus according to the fifth embodiment may further include, in the first to fourth embodiments described above, a detection and evaluation unit downstream of the second mixing unit for detecting the average particle size of inorganic compound particles generated and precipitated by the reaction of the first solution and the second solution, and a control unit for changing the concentration or supply amount of the first solution and / or the second solution supplied from the first raw material supply unit and / or the second raw material supply unit based on the average particle size of the inorganic compound particles detected by the detection and evaluation unit.

[0014] In the inorganic compound manufacturing apparatus according to the sixth aspect, in the first to fourth aspects, the first solution is a first solution in which a first compound containing fluorine and an alkali metal element is dissolved, and the second solution is a second compound containing at least one metal element selected from the group consisting of an alkaline earth metal element, aluminum, gallium, indium, zinc, and yttrium. The inorganic compound particles may be double fluoride composite particles.

[0015] Hereinafter, the inorganic compound particle manufacturing apparatus according to the embodiment of the present disclosure will be described with reference to the accompanying drawings. However, the components, types, combinations, shapes, relative positions, etc. described in this embodiment are not intended to limit the scope of the present disclosure only to those, and are merely illustrative examples.

[0016] (Embodiment 1) FIG. 1A is a schematic diagram showing the configuration of an inorganic compound particle manufacturing apparatus 100 according to Embodiment 1. The inorganic compound particle manufacturing apparatus 100 according to Embodiment 1 includes a first raw material supply unit 10 that supplies a first solution and a second solution, a first mixing unit (first mixer) 20 that mixes the first solution and the second solution, a second raw material supply unit 30 that supplies the first solution and the second solution, and a second mixing unit 40 that mixes the first solution and the second solution with the mixed solution on the downstream side of the first mixing unit 20. According to this inorganic compound particle manufacturing apparatus 100, a second mixing unit 40 is further provided on the downstream side of the first mixing unit 20. As a result, the particle size distribution of the inorganic compound particles generated in the first mixing unit 20 can be kept narrow while increasing the average particle size, and the particle size can be controlled from the nm size to the μm size.

[0017] Hereinafter, each member constituting this inorganic compound particle manufacturing apparatus 100 will be described.

[0018] <First raw material supply unit> The first raw material supply unit 10 supplies the first solution 12 and the second solution 13 to the first mixing unit 20. The first solution 12 and the second solution 13 are respectively supplied from the first liquid delivery unit 14 and the second liquid delivery unit 15 through the first flow path 1 and the second flow path 2. Note that the first solution 12 and the second solution 13 supplied by the first raw material supply unit 10 may be collectively referred to as the first raw material group 11. <Liquid delivery unit> The first liquid delivery unit 14 and the second liquid delivery unit 15 only need to be able to deliver the first solution 12 and the second solution 13 respectively. For example, they are composed of liquid delivery devices such as syringe pumps, plunger pumps, diaphragm pumps, tube pumps, mono pumps, and piezo pumps.

[0019] <Flow path> The materials of the first flow path 1 and the second flow path 2 are not particularly limited. For example, inorganic materials such as glass, quartz, ceramics, and silicon, or resin materials such as thermoplastic resins and thermosetting resins can be used. The inner diameters of the first flow path 1 and the second flow path 2 are, for example, 0.1 mm or more and 1.59 mm or less, but are not limited thereto. In FIG. 1A, the first solution 12 and the second solution 13 are respectively delivered to the respective first flow path 1 and second flow path 2 communicating from the first liquid delivery unit 14 and the second liquid delivery unit 15. For example, the first solution 12 of the first compound, which is an alkali metal fluoride, is delivered to the first flow path 1, and the second solution 13 of the second compound having a metal element different from the alkali metal fluoride is delivered to the second flow path.

[0020] <First solution> The first solution 12 is, for example, a solution of a first compound that is an alkali metal fluoride. Examples of the alkali metal element contained in the first compound include lithium, sodium, potassium, rubidium, and cesium. Specifically, the first compound may contain at least one alkali metal element selected from the group consisting of lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride, and cesium fluoride. In the first channel 1, the first solution 12 is delivered at a concentration that does not become supersaturated. This prevents the first compound contained in the first solution 12 from precipitating within the first channel 1. Furthermore, the concentration of the first solution 12 is set so that when it is mixed with the second solution 13 in the first mixing unit 20, the mixed solution of the first solution 12 and the second solution 13 becomes supersaturated. Specifically, for example, the concentration of the first compound is set to be between 40 mM and 640 mM after mixing the first solution 12 and the second solution 13. Note that while the diagram shows the first solution being stored in a tank, this is merely an example and not the only way to proceed.

[0021] <Second solution> The second solution 13 is a solution of a second compound having a different metal element than the alkali metal fluoride. The second compound is at least one selected from the group consisting of metal chlorides, metal nitrates, metal sulfates, and metal organic acid salts, and may include metal salts other than metal fluorides. The metal element contained in the second compound may be at least one selected from the group consisting of alkaline earth metal elements, aluminum, gallium, indium, zinc, and yttrium. The second compound may include, for example, aluminum chloride. In the second channel 2, the second solution 13 is delivered at a concentration that does not become supersaturated. This prevents the second compound contained in the second solution 13 from precipitating within the second channel 2. Furthermore, the concentration of the second solution 13 is set so that when it is mixed with the first solution in the first mixing unit 20, the mixed solution of the first solution 12 and the second solution 13 becomes supersaturated. Specifically, for example, the concentration of the second compound is set so that after mixing the first and second solutions, the concentration of the second compound is 1 / 20th or less of the concentration of the first compound. The concentrations of the first solution and the second solution mixed in the first mixing unit 20 may be set in stoichiometric ratios for the inorganic compound particles to be generated, but are not limited to this. For example, the concentration of either the first solution or the second solution may be set to be in excess or insufficient from the stoichiometric ratio. Specifically, the concentration of the first solution may be set to be insufficient from the stoichiometric ratio, or the concentration of the second solution may be set to be in excess from the stoichiometric ratio. By doing so, when only the first solution is mixed in the second mixer 41, the particle growth of the inorganic compound particles that have already been generated can be promoted. Note that while the diagram shows the second solution being stored in a tank, this is merely an example and not the only way to proceed.

[0022] <1st mixing section (1st mixer)> The first mixing unit 20 consists of a first mixer that mixes the first solution 12 and the second solution 13 of the first raw material group 11. The first solution 12, which is delivered through the first channel 1, and the second solution 13, which is delivered through the second channel 2, are mixed in the first mixer 20 to form a mixed solution, which is then delivered to the third channel 3. The mixed solution is in a supersaturated state, and inorganic compound particles are generated and precipitate in the mixed solution. The first mixing section (first mixer) 20 only needs to be capable of mixing multiple liquids, and is composed of flow path connecting members such as union tees or manifolds for pipe fittings, or flat plates with grooves or through holes, which are made by bonding or laminating multiple flat plates and fixing them together. Specifically, it may be constructed using, for example, a T-mixer or a three-way joint.

[0023] <Second raw material supply section> The second raw material supply unit 30 supplies the first solution 32 and the second solution 33 to the second mixing unit 40 located downstream of the first mixing unit 20. In Embodiment 1, as shown in Figure 1A, the first solution 32 and the second solution 33 are supplied separately to the second mixing unit 40. The first solution 32 and the second solution 33 are supplied, for example, from the third liquid delivery unit 34 and the fourth liquid delivery unit 35 via the fourth flow path 4 and the fifth flow path 5, respectively. The first solution 32 and the second solution 33 supplied by the second raw material supply unit 30 are sometimes collectively referred to as the second raw material group 31. The second raw material supply unit 30, like the first raw material supply unit 10, can set the concentrations of the first solution 32 and the second solution 33, or supply pure water to lower the concentration.

[0024] The detection and evaluation unit 50 and control unit 60, described later, detect the average particle size of the obtained inorganic compound particles. If feedback control is performed based on the detected average particle size, the concentration or supply amount of the first solution 12 and second solution 13 of the first raw material group 11 and / or the first solution 32 and second solution 33 of the second raw material group 31 may be changed. For example, if inorganic compound particles with a particle size of a desired size or larger have already been generated, the concentration and / or flow rate of the first solution 12 and / or second solution 13 of the first raw material group 11 may be controlled. If the particle size of the generated inorganic compound particles has not reached the desired particle size, the third liquid delivery unit 34 and / or fourth liquid delivery unit 35 may be controlled to change the concentration and / or flow rate of the first solution 32 and / or second solution 33 of the second raw material group 31.

[0025] <Second mixing section> Figure 1B is a schematic diagram showing the change in particle size of inorganic compound particles before and after the supply of an additional second solution in the third mixer 42 of Figure 1. Figure 1C is a schematic diagram showing the particle size distribution and particle size control range of inorganic compound particles obtained by the inorganic compound particle manufacturing apparatus 100 according to Embodiment 1. The second mixing unit 40, located downstream of the first mixing unit 20, mixes the first solution 32 and the second solution 33 of the second raw material group 31, supplied from the second raw material supply unit 30, with the mixed solution of the first solution and the second solution of the first raw material group 11. In Embodiment 1, as shown in Figure 1A, the first solution 32 and the second solution 33 are supplied separately to the second mixing unit 40 sequentially. In this case, the second mixing unit 40 consists of two second mixers 41 and a third mixer 42 that sequentially mix the first solution 32 and the second solution 33. That is, in the second mixer 41, only the first solution is mixed, and the mixture of already generated inorganic compound particles and the added first solution is sent to the sixth flow path 6. In this case, no new particles are generated. In the third mixer 42, the second solution is mixed. In this case, since the second solution is added to the mixture of inorganic compound particles and the first solution, there is a possibility of both the generation of new inorganic compound particles by the first and second solutions, and particle growth on the surface of already existing inorganic compound particles. When the supersaturation level is below the point at which nucleation occurs, as shown in Figure 1B, the first solution 32 is dispersed around the existing inorganic compound particles, so it is considered that particle growth can be achieved on the surface of the inorganic compound particles by the first solution 32 and the second solution 34. Furthermore, as shown in Figure 1C, since particle growth is performed via microchannels, it is possible to generate particles with a narrow particle size distribution. Moreover, the inorganic compound particles initially generated can be grown while maintaining an even narrower particle size distribution, allowing for control over a wide range of particle sizes, from nanometers to micrometers.

[0026] In Embodiment 2, which will be described later, the case in which the first solution and the second solution are mixed and supplied to the second mixing section is explained. In this case, the second mixing section is composed of a single second mixer. The second mixer 41 or the third mixer 42 can be the same mixer as the first mixer, but is not limited to this, and a different mixer may be used. Also, in Embodiment 1, the second mixing section 40 was composed of two mixers 41 and 42, but is not limited to this. For example, the second mixing section may be composed of three or more mixers. In this case, for example, the first solution and / or the second solution may be mixed in multiple stages, or the first solution and the second solution may be mixed alternately and sequentially. By using three or more mixers as described above and performing particle growth multiple times, the average particle size can be controlled over a wide range while maintaining a narrower particle size distribution.

[0027] <Detection and Evaluation Department> The system may include a detection and evaluation unit 50 for detecting the average particle size of inorganic compound particles generated and precipitated by the reaction between the first solution and the second solution. The average particle size may be represented, for example, by the median diameter D50, which is the particle size with a cumulative frequency of 50% in the particle size distribution obtained from the particle size histogram. In this case, the detection and evaluation unit 50 may obtain a histogram of the particle sizes of the inorganic compound particles.

[0028] <Department Head> The system may also include a control unit 60 that changes the supply conditions of the concentration and / or supply amount of the first solution and / or second solution supplied from the first raw material supply unit 10 and / or the second raw material supply unit 30 based on the average particle size of inorganic compound particles detected by the detection and evaluation unit 50. For example, if inorganic compound particles of a size greater than or equal to the desired particle size have already been generated, the flow rates of the first solution 12 and the second solution 13 in the first raw material group 11 may be controlled, since particle growth is performed in two stages. Alternatively, if inorganic compound particles of a size greater than or equal to the desired particle size have not been generated, the flow rate of the second raw material group 31 may be controlled.

[0029] <Recovery and Separation Section> A recovery and separation unit (not shown) for recovering the obtained inorganic compound particles may be provided downstream of the second mixing unit 40 and the detection and evaluation unit 50, which may be provided as needed. The inorganic compound particles generated by the recovery and separation unit are separated and recovered. The separation of the inorganic compound particles is performed, for example, by a solid-liquid separation method from the solution. The solid-liquid separation method is not particularly limited, and for example, filtration or centrifugation can be used.

[0030] When the second compound is a metal chloride, metal nitrate, metal sulfate, or metal organic acid salt, alkali metal chlorides, nitrates, sulfates, or metal organic acid salts are produced as by-products in addition to inorganic compound particles when the first and second compounds are mixed. Therefore, a washing operation may be performed to remove the by-products. Alkali metal compounds may be removed, for example, by washing with a solvent such as water during filtration or centrifugation.

[0031] According to the inorganic compound particle manufacturing apparatus of Embodiment 1, inorganic compound particles with particle sizes in the nanometer range can be manufactured, classification operations are unnecessary, and operation management is simple.

[0032] Next, we will provide an example of the resulting inorganic compound particles.

[0033] <Inorganic compound particles> The inorganic compound particles according to this embodiment 1 may be, for example, polyfluoride composite particles. The polyfluoride composite may contain alkali metal elements. The polyfluoride may contain, for example, at least one alkali metal element selected from the group consisting of lithium, sodium, potassium, rubidium, and cesium. The polyfluoride composite may contain fluorine, alkali metal elements, and additional metal elements other than alkali metal elements as its main components. The additional metal elements may include at least one metal selected from the group consisting of alkaline earth metals, aluminum, gallium, indium, zinc, and yttrium. Specifically, the additional metal elements may include at least one metal selected from the group consisting of magnesium, calcium, strontium, barium, aluminum, gallium, indium, zinc, and yttrium. Polyfluorides containing these metal elements can be easily manufactured into molded bodies, for example, by a pressurized heating method. The term "main components" here means that the total content of fluorine, alkali metal elements, and additional metal elements in the polyfluoride is 80% or more in molar ratio. The above total content may be 85% or more, 90% or more, 95% or more, or 100%.

[0034] The polyfluoride complex may specifically contain at least one of A3AlF6 and ABF3 (wherein the above compositional formula, A represents one or more alkali metal elements as described above, and B represents one or more alkaline earth metal elements as described above). A3AlF6 may contain, for example, at least one selected from the group consisting of Li3AlF6, Li2NaAlF6, Li2KAlF6, Na3AlF6, Na2LiAlF6, Na2KAlF6, K3AlF6, K2LiAlF6, and K2NaAlF6. ABF3 may contain, for example, at least one selected from the group consisting of LiMgF3, NaMgF3, KMgF3, LiCaF3, NaCaF3, and KCaF3. More specifically, the polyfluoride complex may contain at least one selected from the group consisting of Na3AlF6 and NaMgF3.

[0035] The polyfluoride composite may contain fluorine, alkali metal elements, and aluminum as its main components. Here, "main components" means that the total content of fluorine, alkali metal elements, and aluminum in the polyfluoride is 80% or more in molar ratio. This total content may be 85% or more, 90% or more, 95% or more, or 100%.

[0036] The polyfluoride complex may have some of its constituent anions substituted with hydroxide ions and oxide ions. For example, in the case of polyfluorides synthesized in the liquid phase, some of the polyfluoride ions may be substituted with at least one of hydroxide ions and oxide ions.

[0037] (Examples 1-6, Comparative Examples 1-4) The following describes examples and comparative examples of producing sodium hexafluoroaluminate (Na3AlF6), a polyfluoride, as inorganic compound particles using the inorganic compound particle production apparatus according to Embodiment 1.

[0038] (Example 1) In this embodiment 1, two plunger pumps were used as the liquid delivery section of the first raw material supply unit to deliver two types of compound solutions. Here, as compound solutions for synthesizing Na3AlF6 as inorganic compound particles, a first solution was prepared by dissolving sodium fluoride, the first compound, in ultrapure water at 48 mM, and a second solution was prepared by dissolving aluminum chloride hexahydrate, the second compound, in ultrapure water at 40 mM. The flow rate ratio of the second solution to the first solution was set to 1 / 5, and the flow rates of each plunger pump were adjusted so that the flow rate of the mixed solution was 10 mL / min (flow rate of the first solution: flow rate of the second solution = 5:1). At the above flow rates, the concentration of the first compound in the mixed solution after mixing the two liquids is 40 mM. A T-shaped mixer (made of SUS316 stainless steel, with an inner diameter of 0.5 mm) was used as the first mixer for the first and second solutions.

[0039] Two plunger pumps were also used in the liquid delivery section of the second raw material supply unit. The second raw material supply unit supplied a first solution, which was prepared by dissolving sodium fluoride, the first compound, in ultrapure water at a concentration of 48 mM, and a second solution, which was prepared by dissolving aluminum chloride hexahydrate, the second compound, at a concentration of 40 mM. At this time, the flow rate ratio of the second solution to the first solution was 1 / 5 (flow rate of the first solution:flow rate of the second solution = 5:1). If only the second solution were mixed, the flow rate would be 10 mL / min, and the concentration of the first compound in that mixed solution would be 40 mM. When mixing the first solution and the second solution sequentially, T-shaped mixers (made of SUS316 material, with an inner diameter of 0.5 mm) were used as the second mixer 41 and the third mixer 42 of the second mixing section 40. The solution mixed in the third mixer 42 of the second mixing unit 40 passed through a particle detection unit (particle size evaluation unit) located downstream, and the particle size was evaluated. In Example 1, the target average particle size (D50) was set to 10 μm, and the liquid flow rate was adjusted by feedback control in the control unit.

[0040] (Example 2) In Example 2, inorganic compound particles were produced under the same manufacturing conditions as in Example 1, except that the first raw material group consisted of a first solution prepared by dissolving the first compound in ultrapure water at 768 mM, and a second solution prepared by dissolving the second compound in ultrapure water at 640 mM. The concentration of the first compound in the solution obtained by mixing the first and second solutions of the first raw material group was 640 mM. In Example 2, the target particle size was set to 250 nm.

[0041] (Example 3) In Example 3, inorganic compound particles were prepared under the same manufacturing conditions as in Example 1, except that feedback control was not performed.

[0042] (Example 4) In Example 4, inorganic compound particles were prepared under the same manufacturing conditions as in Example 2, except that feedback control was not performed.

[0043] (Example 5) In Example 5, inorganic compound particles were produced under the same manufacturing conditions as in Example 1, except that the first raw material group consisted of a first solution prepared by dissolving the first compound in ultrapure water at 192 mM, and a second solution prepared by dissolving the second compound in ultrapure water at 160 mM. The concentration of the first compound in the solution obtained by mixing the first and second solutions of the first raw material group was 160 mM. In Example 5, the target particle size was set to 500 nm.

[0044] (Example 6) In Example 6, inorganic compound particles were prepared under the same manufacturing conditions as in Example 5, except that feedback control was not performed.

[0045] (Comparative Example 1) In Comparative Example 1, inorganic compound particles were produced under the same manufacturing conditions as in Example 1, except that feedback control was not performed and the second raw material group was not used.

[0046] (Comparative Example 2) In Comparative Example 2, inorganic compound particles were produced under the same manufacturing conditions as in Example 2, except that feedback control was not performed and the second raw material group was not used.

[0047] (Comparative Example 3) In Comparative Example 3, inorganic compound particles were produced under the same manufacturing conditions as in Example 5, except that feedback control was not performed and the second raw material group was not used.

[0048] (evaluation) If the particle size evaluation value (average particle size) was within 5% of the target particle size, it was marked with ◎; if it was between 5% and 10%, it was marked with ○; and otherwise, it was marked with ×.

[0049] Figure 2 is Table 1, which shows the manufacturing conditions for inorganic compound particles and the characteristics of the obtained inorganic compound particles for Examples 1 to 6 and Comparative Examples 1 to 3 using the inorganic compound particle manufacturing apparatus shown in Figure 1A.

[0050] As shown in Table 1 of Figure 2, in Examples 1 to 6, which used an inorganic compound particle manufacturing apparatus having a second mixing section in addition to the first mixing section, it was possible to reach the target average particle size within the error range. In contrast, in Comparative Examples 1 to 3, which used an inorganic compound particle manufacturing apparatus without a second mixing section, it was not possible to reach the target average particle size within the error range.

[0051] Furthermore, comparing Examples 1, 2, and 5 with Examples 3, 4, and 6, it can be seen that when feedback control is performed using the detection and evaluation unit and the control unit, the average particle size of the obtained particles is closer to the target average particle size, taking errors into account, and the yield is also higher.

[0052] (Embodiment 2) Figure 3 is a schematic diagram showing the configuration of the inorganic compound particle manufacturing apparatus 100a according to Embodiment 2. The inorganic compound particle manufacturing apparatus 100a according to Embodiment 2 differs from the inorganic compound particle manufacturing apparatus according to Embodiment 1 in that, as shown in Figure 3, the first raw material supply unit 30 supplies a mixed solution 36 obtained by mixing the first solution and the second solution, and the second mixing unit 40a is composed of a single second mixer 41, in which the mixed solution is mixed with the solution containing the generated inorganic compound particles. The other configurations are substantially the same as the inorganic compound particle manufacturing apparatus according to Embodiment 1. In this case, the concentrations of the first solution and the second solution are set so that the concentration of the mixed solution 36 is below the saturation concentration so that inorganic compound particles do not precipitate before being supplied to the second mixing unit 40a. This allows the second mixing section 40a to be constructed with a single second mixer 41, thus enabling miniaturization. Furthermore, it reduces manufacturing instability caused by pulsation in the liquid delivery section.

[0053] (Examples 7-10 and Comparative Examples 4-5) The following describes examples and comparative examples of producing sodium hexafluoroaluminate (Na3AlF6), a polyfluoride, as inorganic compound particles using the inorganic compound particle production apparatus according to Embodiment 2.

[0054] (Example 7) In this embodiment 7, two plunger pumps were used as the liquid delivery unit for the first raw material group, and two types of compound solutions were delivered separately. Here, as compound solutions for synthesizing Na3AlF6, a first solution was prepared by dissolving sodium fluoride, the first compound, in ultrapure water at 48 mM, and a second solution was prepared by dissolving aluminum chloride hexahydrate, the second compound, in ultrapure water at 40 mM. The flow rate ratio of the second solution to the first solution was set to 1 / 5, and the flow rates of each plunger pump were adjusted so that the flow rate of the mixed solution was 10 mL / min (flow rate of the first solution: flow rate of the second solution = 5:1). At the above flow rates, the concentration of the first compound after mixing the two solutions is 40 mM. A T-shaped mixer (made of SUS316 stainless steel, with an inner diameter of 0.5 mm) was used as the first mixer for the first and second solutions. A plunger pump was also used for the liquid delivery section of the second raw material group. The second raw material group used a pre-mixed solution consisting of a first solution (sodium fluoride, the first compound, dissolved in ultrapure water at 24 mM) and a second solution (aluminum chloride hexahydrate, the second compound, dissolved at 20 mM). At this time, the volume ratio of the second solution to the first solution was 1 / 5 (volume of first solution:volume of second solution = 5:1), and the concentration of the first compound after mixing the two solutions was 20 mM. This solution was delivered at a rate of 10 mL / min. A T-shaped mixer (made of SUS316 stainless steel, with an inner diameter of 0.5 mm) was also used in the second mixer for mixing the first and second raw material groups. The solution mixed in the second mixer passed through a particle detection unit (particle size evaluation unit) located downstream, and its particle size was evaluated. In Example 1, the target particle size was set to 10 μm, and feedback control was performed in the control unit to adjust the flow rate of the first raw material group and / or the second raw material group.

[0055] (Example 8) In Example 8, inorganic compound particles were prepared under the same manufacturing conditions as in Example 7, except that the first raw material group consisted of a first solution prepared by dissolving the first compound in ultrapure water at 768 mM, and a second solution prepared by dissolving the second compound in ultrapure water at 640 mM. The concentration of the first compound in the solution prepared by mixing the first raw material group was 640 mM. In Example 2, the target particle size was set to 250 nm.

[0056] (Example 9) In Example 9, inorganic compound particles were prepared under the same manufacturing conditions as in Example 1, except that feedback control was not performed.

[0057] (Example 10) In Example 10, inorganic compound particles were prepared under the same manufacturing conditions as in Example 2, except that feedback control was not performed.

[0058] (Comparative Example 4) In Comparative Example 4, inorganic compound particles were produced under the same manufacturing conditions as in Example 7, except that feedback control was not performed and the second raw material group was not used.

[0059] (Comparative Example 5) In Comparative Example 5, inorganic compound particles were produced under the same manufacturing conditions as in Example 8, except that feedback control was not performed and the second raw material group was not used.

[0060] (evaluation) If the particle size evaluation value (average particle size) was within 5% of the target particle size, it was marked with ◎; if it was between 5% and 10%, it was marked with ○; and otherwise, it was marked with ×.

[0061] Figure 4 is shown in Table 2, which illustrates the manufacturing conditions for inorganic compound particles in Examples 7 to 10 and Comparative Examples 4 to 5 using the inorganic compound particle manufacturing apparatus shown in Figure 3, as well as the characteristics of the obtained inorganic compound particles.

[0062] As shown in Table 2 of Figure 4, in Examples 7 to 10, which used an inorganic compound particle manufacturing apparatus having a second mixing section in addition to the first mixing section, it was possible to reach the target average particle size within the error range. In contrast, in Comparative Examples 4 and 5, which used an inorganic compound particle manufacturing apparatus without a second mixing section, it was not possible to reach the target average particle size within the error range.

[0063] Furthermore, comparing Examples 7 and 8 with Examples 9 and 10, it can be seen that when feedback control is performed using the detection and evaluation unit and the control unit, the average particle size of the obtained particles is closer to the target average particle size, taking errors into account, and the yield is also higher. [Industrial applicability]

[0064] The inorganic compound particle manufacturing apparatus described herein can produce inorganic compound particles with a particle size in the nanometer range. [Explanation of Symbols]

[0065] 1. First channel 2. Second channel 3. Third channel 4. Fourth channel 5. Fifth channel 6. Sixth channel 7. The seventh channel 8. Channel 8 9. The 9th channel 10 1st raw material supply section 11 First raw material group 12 First solution 13 Second solution 14. First liquid delivery section 15. Second liquid delivery section 20 1st mixing section (1st mixer) 30 2nd raw material supply section 31 Second raw material group 32 First solution 33 Second solution 34 Third liquid delivery section 35. Fourth liquid delivery section 36 Mixed solution 37. Fifth liquid delivery section 40 2nd mixing section 41 Second mixer 42 Third mixer 50 Detection and Evaluation Unit 60 Control Unit 100, 100a inorganic compound particle manufacturing equipment

Claims

1. A first raw material supply unit that supplies the first solution and the second solution, A first mixing unit having a first mixer for mixing a first solution and a second solution supplied from the first raw material supply unit, A second raw material supply unit that supplies the first solution and the second solution, Downstream of the first mixing unit, a second mixing unit mixes the first solution and the second solution supplied from the second raw material supply unit with the mixed solution of the first solution and the second solution, An inorganic compound particle manufacturing apparatus equipped with the following features.

2. The inorganic compound particle manufacturing apparatus according to claim 1, wherein the second raw material supply unit supplies the first solution and the second solution separately to the second mixing unit.

3. The second mixing unit is, Downstream of the first mixing unit, a second mixer mixes the first solution from the second raw material supply unit, Downstream of the second mixer, a third mixer mixes the second solution from the second raw material supply unit, An apparatus for producing inorganic compound particles according to claim 2, comprising:

4. The inorganic compound particle manufacturing apparatus according to claim 1, wherein the second raw material supply unit supplies a mixed solution obtained by mixing the first solution and the second solution to the second mixing unit at a concentration below saturation.

5. Downstream of the second mixing section, there is a detection and evaluation unit for detecting the average particle size of inorganic compound particles generated and precipitated by the reaction between the first solution and the second solution, A control unit that changes the concentration or supply amount of the first solution and / or the second solution supplied from the first raw material supply unit and / or the second raw material supply unit based on the average particle size of the inorganic compound particles detected by the detection and evaluation unit, The inorganic compound particle manufacturing apparatus according to claims 1 to 4, further comprising:

6. The first solution is a solution in which a first compound containing fluorine and an alkali metal element is dissolved. The second solution is a solution in which a second compound containing at least one metal element selected from the group consisting of alkaline earth metal elements, aluminum, gallium, indium, zinc, and yttrium is dissolved. The inorganic compound particle manufacturing apparatus according to claims 1 to 4, wherein the inorganic compound particles are complex fluoride particles.

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