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WO2025115287A1 - Procédé de séparation et de récupération d'un composé de terres rares et d'un composé métallique à partir de déchets de condensateurs céramiques multicouches après calcination - Google Patents

Procédé de séparation et de récupération d'un composé de terres rares et d'un composé métallique à partir de déchets de condensateurs céramiques multicouches après calcination Download PDF

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Publication number
WO2025115287A1
WO2025115287A1 PCT/JP2024/026745 JP2024026745W WO2025115287A1 WO 2025115287 A1 WO2025115287 A1 WO 2025115287A1 JP 2024026745 W JP2024026745 W JP 2024026745W WO 2025115287 A1 WO2025115287 A1 WO 2025115287A1
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metal
rare earth
ceramic
electrode layer
component
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English (en)
Japanese (ja)
Inventor
健一 山口
大介 濱田
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Murata Manufacturing Co Ltd
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Murata Manufacturing Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B1/00—Preliminary treatment of ores or scrap
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B1/00—Preliminary treatment of ores or scrap
    • C22B1/02—Roasting processes
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B15/00—Obtaining copper
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B23/00—Obtaining nickel or cobalt
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
    • C22B3/04—Extraction of metal compounds from ores or concentrates by wet processes by leaching
    • C22B3/06—Extraction of metal compounds from ores or concentrates by wet processes by leaching in inorganic acid solutions, e.g. with acids generated in situ; in inorganic salt solutions other than ammonium salt solutions
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
    • C22B3/04—Extraction of metal compounds from ores or concentrates by wet processes by leaching
    • C22B3/12—Extraction of metal compounds from ores or concentrates by wet processes by leaching in inorganic alkaline solutions
    • C22B3/14—Extraction of metal compounds from ores or concentrates by wet processes by leaching in inorganic alkaline solutions containing ammonia or ammonium salts
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B59/00—Obtaining rare earth metals
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B7/00—Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or applied to the winning of more than two metals

Definitions

  • This invention relates to a method for separating and recovering rare earth and metal components from post-sintering waste from multilayer ceramic capacitors.
  • a multilayer ceramic capacitor includes a laminate having an internal electrode layer and a ceramic layer, and an external electrode.
  • the internal electrode layer contains a metal component such as Ni, and the ceramic layer is formed of BaTiO 3 , etc.
  • Patent documents 1 to 4 disclose a method for recovering Ni, which is mainly used in the internal electrode layer, and also disclose that BaTiO 3 contained in the ceramic layer is separated in the process of recovering Ni.
  • Patent documents 1 to 4 disclose the recovery of Ni, but do not disclose the recovery of rare earth components. However, it is desirable to be able to recover not only metal components such as Ni, but also rare earth components.
  • the main object of this invention is to provide a method for separating and recovering rare earth and metal components from post-sintering waste of multilayer ceramic capacitors.
  • the method for separating and recovering rare earth components and metal components from post-sintering waste of multilayer ceramic capacitors comprises the steps of: (A) preparing sintered waste of a multilayer ceramic capacitor, the multilayer ceramic capacitor comprising a laminate including a ceramic layer and an internal electrode layer, and a fired electrode layer disposed on the laminate as an outermost layer and connected to the internal electrode layer, the ceramic layer having an aggregate of a plurality of ceramic particles, a rare earth-containing material including a rare earth component is contained in grain boundaries between the plurality of ceramic particles, the internal electrode layer includes a first metal component which is a magnetic base metal, the fired electrode layer includes a second metal component which is a non-magnetic precious metal, and the ceramic layer, the internal electrode layer, and the fired electrode layer are sintered; (B) A step of obtaining a ceramic fine-particle having a fine ceramic layer, a rare earth-containing material, a first metal fine-particle having a fine internal electrode layer, and a second metal fine-particle having a
  • rare earth components and metal components can be separated and recovered from the post-sintering waste.
  • metal components a first metal component contained in the internal electrode layer and a second metal component contained in the external electrode can be separated and recovered.
  • the method for separating and recovering rare earth components and metal components from post-sintering waste of multilayer ceramic capacitors comprises the steps of: (A) a step of preparing fired waste of a multilayer ceramic capacitor, the fired waste comprising a laminate including a ceramic layer and an internal electrode layer, a fired electrode layer disposed on the laminate and connected to the internal electrode layer, and a first-stage plating layer disposed on the fired electrode layer as an outermost layer, the ceramic layer having an aggregate of a plurality of ceramic particles, rare earth-containing matter containing a rare earth component is contained in grain boundaries between the plurality of ceramic particles, the internal electrode layer contains a first metal component which is a magnetic base metal, the fired electrode layer contains a second metal component which is a non-magnetic precious metal, the first-stage plating layer contains the first metal component, and the ceramic layer, the internal electrode layer, and the fired electrode layer are sintered; (B) A step of pulverizing the fired waste to obtain a ceramic micro-fine product having a fine ceramic layer,
  • rare earth components and metal components can be separated and recovered from the post-sintering waste.
  • metal components a first metal component contained in the internal electrode layer and a second metal component contained in the external electrode can be separated and recovered.
  • the method for separating and recovering rare earth components and metal components from post-sintering waste of multilayer ceramic capacitors comprises the steps of: (A) a step of preparing sintered waste of a multilayer ceramic capacitor, the multilayer ceramic capacitor comprising: a laminate including a ceramic layer and an internal electrode layer; a fired electrode layer disposed on the laminate and connected to the internal electrode layer; a first-stage plating layer disposed on the fired electrode layer; and a second-stage plating layer disposed on the first-stage plating layer as an outermost layer, the ceramic layer having an aggregate of a plurality of ceramic particles, a rare earth-containing material containing a rare earth component is contained in grain boundaries between the plurality of ceramic particles; the internal electrode layer includes a first metal component which is a base metal having magnetism; the fired electrode layer includes a second metal component which is a precious metal having no magnetism; the first-stage plating layer includes the first metal component; the second-stage plating layer includes a third metal component; and the ceramic layer, the
  • rare earth components and metal components can be separated and recovered from the post-sintering waste.
  • metal components a first metal component contained in the internal electrode layer and a second metal component contained in the external electrode can be separated and recovered.
  • This invention provides a method for separating and recovering rare earth and metal components from post-sintering waste from multilayer ceramic capacitors.
  • FIG. 1 is a flow diagram showing a method for separating and recovering rare earth components and metal components from waste after firing of a multilayer ceramic capacitor (firing for firing electrode layers), according to a first embodiment of the present invention.
  • 1 is an external perspective view showing an example of a multilayer ceramic capacitor according to a first embodiment of the present invention
  • 3 is a cross-sectional view taken along line III-III in FIG. 2.
  • 2 is a schematic diagram showing the state of unsintered ceramic layers and unsintered internal electrode layers in a cross section parallel to a plane including the longitudinal direction and stacking direction in a laminated chip.
  • FIG. FIG. 4 is an enlarged view of a portion ⁇ in FIG. 3, and is a schematic diagram showing the state of each layer after firing for a fired electrode layer.
  • FIG. 6 is a partial enlarged view of the ceramic layer of FIG. 5 .
  • 1 is a cross-sectional view (1) of a multilayer ceramic capacitor according to a second embodiment of the present invention, taken along a plane including the length direction and lamination direction.
  • FIG. 11 is a cross-sectional view (2) of another aspect of the multilayer ceramic capacitor according to the second embodiment of the present invention, taken along a plane including the length direction and lamination direction.
  • FIG. 1 is a flow diagram showing a method for separating and recovering rare earth components and metal components from waste after firing of a multilayer ceramic capacitor (firing for firing electrode layers), the method including a plating removal step.
  • First Embodiment 1 Separation and Recovery Method A method for separating and recovering rare earth components and metal components (first metal component and second metal component) from post-sintering waste of multilayer ceramic capacitors (sintering for fired electrode layers) according to a first embodiment of the present invention will be described.
  • FIG. 1 is a flow diagram showing a method for separating and recovering rare earth components and metal components from post-sintering waste (sintering for fired electrode layers) of multilayer ceramic capacitors according to a first embodiment of the present invention.
  • post-sintering waste sining for fired electrode layers
  • FIG. 1 is a flow diagram showing a method for separating and recovering rare earth components and metal components from post-sintering waste (sintering for fired electrode layers) of multilayer ceramic capacitors according to a first embodiment of the present invention.
  • post-sintering waste sining for fired electrode layers
  • the post-sintering waste will now be described.
  • FIG. 2 is an external perspective view showing an example of a multilayer ceramic capacitor according to a first embodiment of the present invention.
  • Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2.
  • a two-terminal multilayer ceramic capacitor will be described as an example of the multilayer ceramic capacitor 10.
  • the multilayer ceramic capacitor 10 includes, for example, a rectangular parallelepiped laminate 12 and external electrodes 30 arranged on both ends of the laminate 12.
  • the laminate 12 has a plurality of stacked ceramic layers 14 and a plurality of internal electrode layers 16 stacked on the ceramic layers 14. Furthermore, the laminate 12 has a first main surface 12a and a second main surface 12b that face each other in a height direction (stacking direction) x, a first side surface 12c and a second side surface 12d that face each other in a width direction y perpendicular to the height direction x, and a first end surface 12e and a second end surface 12f that face each other in a length direction z perpendicular to the height direction x and the width direction y.
  • the ceramic layers 14 and the internal electrode layers 16 are stacked in the height direction x.
  • the first internal electrode layer 16a and the second internal electrode layer 16b can be made of, for example, a conductive material containing a magnetic base metal, and the magnetic base metal can be a simple metal or an alloy.
  • magnetic base metals include Ni and Fe. Note that, here, a metal that has a higher ionization tendency than hydrogen is referred to as a base metal.
  • the ceramic layer 14 has an aggregate of a plurality of ceramic particles (each BT in FIG. 5 described later, also called a ceramic sintered body). Each ceramic particle can be formed, for example, by a dielectric material as the ceramic material.
  • a dielectric material for example, a dielectric ceramic having a perovskite structure with a perovskite type compound containing a component such as BaTiO 3 , CaTiO 3 , SrTiO 3 , or CaZrO 3 as the main component can be used.
  • a rare earth component is added to the dielectric material as an additive according to the desired characteristics of the laminate 12.
  • the rare earth component to be added for example, at least one of Dy, Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Ho, Er, Tm, Yb, and Lu can be mentioned.
  • the above-mentioned dielectric material may be used with the addition of a minor component, such as a Mn compound, an Fe compound, a Cr compound, a Co compound, or a Ni compound, in a content less than that of the main component.
  • a minor component such as a Mn compound, an Fe compound, a Cr compound, a Co compound, or a Ni compound, in a content less than that of the main component.
  • At least one of Si, Mg, Ba, and Mn may be added as an additional additive to the above-mentioned main component.
  • these minor components and additives may cause a deterioration in the quality of the rare earth components during the separation and recovery of the rare earth components, these minor components and additives may be omitted.
  • external electrodes 30 are arranged on the first end face 12e side and the second end face 12f side of the laminate 12.
  • the external electrode 30 has a first external electrode 30a and a second external electrode 30b.
  • the first external electrode 30a is connected to the first internal electrode layer 16a and is disposed on at least the surface of the first end face 12e.
  • the second external electrode 30b is connected to the second internal electrode layer 16b and is disposed on at least the surface of the second end face 12f.
  • the external electrode 30 includes a baked electrode layer 32.
  • the first external electrode 30a includes a first baked electrode layer 32a.
  • the second external electrode 30b includes a second baked electrode layer 32b.
  • the baked electrode layer 32 is the outermost layer of the multilayer ceramic capacitor 10. In other words, the baked electrode layer 32 is the outermost layer of the layers disposed on the laminate 12.
  • the baked electrode layer 32 may be formed from a baked layer containing a glass component and a second metal component which is a non-magnetic precious metal.
  • the second metal component of the baked layer includes at least one selected from Cu, Ag, etc.
  • the glass component of the baked layer includes an oxide containing at least one element selected from B, Si, Ba, Mg, Al, Li, etc.
  • a metal that has a lower ionization tendency than hydrogen is referred to as a precious metal.
  • Step 1 a dielectric sheet for the ceramic layer and a conductive paste for the internal electrode layer are prepared.
  • the dielectric sheet for the ceramic layer is formed from a dielectric slurry containing, but not limited to, BaTiO3 as a main component and Dy as an additive.
  • the conductive paste for the internal electrode layer is formed from, but not limited to, Ni as a main component.
  • the dielectric sheet and the conductive paste for the internal electrode layer include a binder and a solvent.
  • the binder and the solvent are composed of a resin component, and the resin component can be, for example, various known thermosetting resins such as epoxy resin, phenoxy resin, phenol resin, urethane resin, and polyimide resin.
  • Step 2 a conductive paste for the internal electrode layers is printed in a predetermined pattern on the dielectric sheet, for example by screen printing or gravure printing. This prepares a dielectric sheet on which the pattern of the first internal electrode layer is formed, and a dielectric sheet on which the pattern of the second internal electrode layer is formed.
  • outer layer dielectric sheets that do not have the internal electrode layer pattern printed on them are also prepared.
  • a predetermined number of dielectric sheets for the outer layers, on which the pattern of the internal electrode layer is not printed, are stacked.
  • a dielectric sheet on which the pattern of the first internal electrode layer is printed, and a dielectric sheet on which the pattern of the second internal electrode layer is printed are stacked in order on top of the dielectric sheets to form an inner layer portion.
  • a predetermined number of dielectric sheets for the outer layers, on which the pattern of the internal electrode layer is not printed, are stacked on top of the inner layer portion.
  • the dielectric sheets are sometimes referred to as the ceramic layers when unfired, that is, the ceramic layers before the laminated chip is fired.
  • the pattern of the internal electrode layers is sometimes referred to as the internal electrode layers when unfired, that is, the internal electrode layers before the laminated chip is fired.
  • Step 3 the laminated sheet is pressed in the stacking direction using a means such as a hydrostatic press to produce a laminated block.
  • FIG. 4 is a schematic diagram showing the state of the unfired ceramic layers and the unfired internal electrode layers in a cross section parallel to a plane including the length direction and the lamination direction in the laminated chip.
  • FIG. 4 shows a cross section of the laminated chip on which the external electrodes 30 have not yet been formed.
  • the laminated chip in FIG. 4 is in a state prior to degreasing (step 5) and firing of the laminated chip (step 6). However, the resin component contained in the laminated chip is not shown.
  • the laminated chip is formed by alternately stacking the unfired internal electrode layers 16_U and the unfired ceramic layers 14_U.
  • the laminated chip as a whole contains a first metal powder (Ni_P in FIG. 4), ceramic powders (BT 1 _P, BT 2 _P in FIG. 4), rare earth powder (Dy_P in FIG. 4), and a resin component.
  • the first metal powder mainly constitutes the internal electrode layer 16_U when unsintered.
  • the ceramic powder mainly constitutes the ceramic layer 14_U when unsintered.
  • the first metal powder is, for example, an aggregate of first metal atoms, which is the first metal component.
  • the first metal powder can be made of a conductive material containing a magnetic base metal, and the magnetic base metal can be either an elemental metal or an alloy. Examples of magnetic base metals include Ni and Fe.
  • the ceramic powder is an aggregate of dielectric materials.
  • examples of the dielectric materials include BaTiO 3 , CaTiO 3 , SrTiO 3 , and CaZrO 3 .
  • the ceramic powder includes a first ceramic powder and a second ceramic powder. The second ceramic powder has a smaller particle size than the first ceramic powder.
  • Rare earth powder is an aggregate of rare earth atoms, which are rare earth components.
  • the rare earth atoms can be at least one of Dy, Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Ho, Er, Tm, Yb, and Lu.
  • the resin components are binders and solvents for producing conductive pastes for the dielectric sheets and internal electrode layers.
  • the binders and solvents are composed of resin components, and various known thermosetting resins such as epoxy resins, phenoxy resins, phenolic resins, urethane resins, and polyimide resins can be used as the resin components.
  • FIG. 4 shows the state of various powders contained in the laminated chip before the degreasing in (step 5) and the firing of the laminated chip in (step 6).
  • the resin component is omitted.
  • the ceramic layer 14_U when unfired is mainly composed of the first ceramic powder (BT 1 _P in FIG. 4).
  • the first ceramic powder and the rare earth powder (Dy_P in FIG. 4) are at least partially attached to each other.
  • the rare earth powder is mainly attached to the surface of the first ceramic powder, and basically, the rare earth powder does not penetrate into the inside of the first ceramic powder and is not chemically bonded.
  • the internal electrode layer 16_U when unfired is mainly composed of the first metal powder (Ni_P in FIG. 4).
  • the first metal powder and the second ceramic powder (BT 2 _P in FIG. 4) are at least partially attached to each other.
  • the second ceramic powder is mainly attached to the surface of the first metal powder, and the second ceramic powder is not basically chemically bonded to the inside of the first metal powder.
  • the meaning of "attached” may include that the powders such as the first metal powder, the ceramic powder, and the rare earth powder are partially chemically bonded to each other.
  • the chemical bond is a bond in which a plurality of atoms are attracted to each other by positive and negative charges, such as an ionic bond, a covalent bond, or a metallic bond.
  • Step 5 Next, the resin components in the laminated chip are removed.
  • the removal of the resin components in step 5 is a degreasing step in the manufacturing process.
  • the degreasing temperature in the degreasing step 5 is, for example, higher than 800° C. and lower than 1000° C.
  • Step 6 the laminated chip is fired to produce the laminate 12.
  • the firing temperature for the laminated chip depends on the materials of the ceramic layers and internal electrode layers, which are dielectrics, but is preferably higher than 1000°C and lower than 1400°C, for example.
  • Steps 1 to 6 are the laminate formation process. Note that the firing in step 6 is sometimes called firing the laminated chip. This firing turns the unfired laminated chip into the laminate 12. Furthermore, the unfired internal electrode layer 16_U and the unfired ceramic layer 14_U are fired to become the internal electrode layer 16 and the ceramic layer 14.
  • a baked electrode layer paste containing a plurality of second metal powders (e.g., Cu powder) is applied to the first and second end faces 12e, 12f of the laminate 12 and fired to form a baked electrode layer 32, which is an external electrode 30.
  • the second metal powder is, for example, an aggregate of second metal atoms, which is a second metal component.
  • Each second metal powder in the baked electrode layer paste is dispersed alone in the baked electrode layer paste, or is dispersed by adhering to other powders including other second metal powders. In other words, in the baked electrode layer paste, each second metal powder is not chemically bonded to other second metal powders or powders such as other additives.
  • the baked electrode layer paste is fired, so that the second metal powders are in a sintered state.
  • the firing temperature of the baked electrode layer paste is preferably 700°C or higher and 900°C or lower.
  • the firing in step 7 may be referred to as firing for the baked electrode layer.
  • FIG. 5 is an enlarged view of the ⁇ portion of Figure 3, and is a schematic diagram showing the state of each layer after firing for the fired electrode layers.
  • Figure 6 is a partial enlarged view of the ceramic layers in Figure 5. After firing for the fired electrode layers, the multilayer ceramic capacitor 10 is in a sintered state with each part, such as the ceramic layer 14, the internal electrode layer 16, and the external electrode 30.
  • the ceramic powder (BT 1 _P, BT 2 _P in FIG. 4 ) is fired to become ceramic particles BT (BT in FIG. 5 ) in a sintered state as shown in FIG. 5 .
  • the ceramic powder (BT 1 _P, BT 2 _P in FIG. 4 ) is fired, for example, in the stacked chip (step 6 ), to form the fired ceramic particles BT.
  • the ceramic particles BT in a sintered state may be called a ceramic sintered body BT.
  • the ceramic powder is fired to develop the contact between the ceramic particles from point contact to surface contact. This causes the chemical bonding between the ceramic powders to progress, forming integrated ceramic particles BT (ceramic sintered body BT).
  • the ceramic particles BT may be formed by partially chemically bonding the ceramic powder with the rare earth powder.
  • the ceramic layer 14 includes an aggregate of a plurality of ceramic particles BT.
  • most of the first ceramic powder (BT 1 _P in FIG. 4 ) forms the ceramic layer 14, for example, by firing the laminated chip in (step 6).
  • most of the second ceramic powder (BT 2 _P in FIG. 4 ) adhering to the first metal powder (Ni_P in FIG. 4 ) forms the ceramic layer 14, for example, by firing the laminated chip in (step 6).
  • most of the second ceramic powder (BT 2 _P in FIG. 4 ) is pushed out from the fired internal electrode layer 16 without basically bonding with the fired internal electrode layer 16, and is fired together with the first ceramic powder to form the ceramic layer 14.
  • each ceramic particle BT is formed by a core shell 40 shown in FIG. 6.
  • the core shell 40 has a core portion 42 including a central portion of the core shell 40, and a shell portion 44 covering the surface of the core portion 42.
  • the core portion 42 is mainly formed of a ceramic material.
  • the shell portion 44 is formed by incorporating, for example, a rare earth component, which is an additive, into the ceramic material.
  • the shell portion 44 may also incorporate other subcomponents such as Mn compounds.
  • a grain boundary 50 exists at the boundary between the ceramic particles BT.
  • the grain boundary 50 contains a rare earth inclusion.
  • the rare earth inclusion contains the rare earth component in the form of, for example, an oxide.
  • An example of the oxide of the rare earth component is dysprosium oxide (Dy 2 O 3 ).
  • the rare earth inclusion may also contain, for example, silicon dioxide (SiO 2 ), manganese dioxide (MnO 2 ), etc.
  • SiO 2 silicon dioxide
  • MnO 2 manganese dioxide
  • each ceramic particle BT has a core-shell structure.
  • each ceramic particle BT may have a structure in which the rare earth component or the like is incorporated up to the center of the ceramic particle BT.
  • ceramic particles BT having such a structure and ceramic particles BT having a core-shell structure may be mixed in the ceramic layer 14.
  • the internal electrode layer 16 is formed by firing the first metal powder (Ni_P in FIG. 4) to form the first metal particles (Ni in FIG. 5) in a sintered state as shown in FIG. 5.
  • the first metal powder (Ni_P in FIG. 4) forms the fired internal electrode layer 16, for example, by firing the stacked chip in (step 6).
  • the Ni powder which is the first metal powder, is sintered to form Ni particles (first metal particles).
  • the first metal particles in a sintered state may also be called a first metal sintered body.
  • the first metal powder is heated by firing, and the contact between the first metal powder particles develops from point contact to surface contact. As a result, the bonding between the first metal powder particles progresses to form integrated first metal particles (first metal sintered body).
  • the internal electrode layer 16 includes an aggregate of multiple first metal particles.
  • the baked electrode layer 32 is formed by firing the second metal powder (e.g., Cu powder) for the baked electrode layer, and is turned into second metal particles (Cu in FIG. 5) in a sintered state as shown in FIG. 5.
  • the Cu powder which is the second metal powder
  • the second metal particles in a sintered state may be called a second metal sintered body.
  • the second metal powder is heated by firing for the baked electrode layer, and the contact between the second metal powder develops from point contact to surface contact. As a result, the bonding between the second metal powder progresses to form integrated second metal particles (second metal sintered body).
  • the baked electrode layer 32 includes an aggregate of multiple second metal particles.
  • the multilayer ceramic capacitor 10 is manufactured through the above-mentioned manufacturing process.
  • the post-firing waste is waste after the firing for the fired electrode layer in (step 7) when the multilayer ceramic capacitor 10 is manufactured by the manufacturing method for the multilayer ceramic capacitor 10 described above.
  • the separation and recovery method in Fig. 1 includes a common separation and recovery route, a rare earth component separation and recovery route, a first metal component separation and recovery route, and a second metal component separation and recovery route.
  • the rare earth component separation and recovery route and the first metal component separation and recovery route branch off from the common separation and recovery route.
  • the second metal component separation and recovery route branches off from the rare earth component separation and recovery route.
  • the common separation and recovery route includes, for example, preparation of post-calcination waste in step (A), pulverization in step (B), and magnetic separation in step (C).
  • the process branches into a rare earth component separation and recovery route and a first metal component separation and recovery route.
  • the rare earth component separation and recovery route can include, for example, dissolution of the second separated material in step (D), and can further include filtration in step (F), and neutralization in step (G).
  • the second metal component separation and recovery route branches off from the rare earth component separation and recovery route.
  • the second metal component separation and recovery route can include, for example, dissolution of the undissolved material in step (E), and can further include filtration in step (H).
  • the first metal component separation and recovery route can include, for example, dissolution of the first separated material in step (I), and can further include filtration in step (J).
  • post-sintering waste of a multilayer ceramic capacitor sintered electrode layers
  • the post-sintering waste is as described above.
  • the post-sintering waste includes a laminate 12 including ceramic layers 14 and internal electrode layers 16, and a sintered electrode layer 32.
  • the ceramic layers 14, the internal electrode layers 16, and the sintered electrode layer 32 are in a sintered state.
  • step (B) the fired waste is pulverized.
  • the fired waste is pulverized by crushing.
  • the pulverization is performed, but not limited to, for example, by a method of applying a pulverizing force by vibration to the object using a vibration mill or the like, a method of grinding the object, a method of applying a pulverizing force by impact to the object, and the like. It is preferable to pulverize the fired waste to an extent that it is easy to separate in the magnetic separation in step (C) described later.
  • the ceramic pulverized product includes, for example, a ceramic material such as BaTiO 3 , CaTiO 3 , SrTiO 3 , or CaZrO 3 .
  • the rare earth-containing material may include, for example, dysprosium oxide ( Dy2O3 ), and may also include, for example, silicon dioxide ( SiO2 ), manganese dioxide ( MnO2 ), etc.
  • the first finely divided metal material may include, for example, a first metal component such as Ni and Fe.
  • the second finely divided metal material may include, for example, a second metal component such as Cu.
  • the average particle size of the post-calcination waste after being finely divided is not limited. The average particle size may be determined, for example, by using a sieve.
  • the post-calcination waste after being pulverized in step (B) is magnetically separated using a magnet. That is, the post-calcination waste is separated into a first separated matter and a second separated matter by magnetic separation and recovered.
  • the first separated material includes a first metal microparticle (Ni in FIG. 1) and a ceramic microparticle (BT in FIG. 1).
  • the first metal microparticle includes a first metal component, which is a magnetic base metal.
  • the ceramic microparticle does not have magnetic properties.
  • the first separated material is separated as a magnetic material by magnetic separation. Specifically, in the first separated material, when the magnetic first metal microparticle is separated as a magnetic material, the non-magnetic ceramic microparticle is entangled with this first metal microparticle.
  • the second separated material includes a second metal fine particle (Cu in FIG. 1), a rare earth-containing material ( Dy2O3 in FIG. 1), and a ceramic fine particle (BT in FIG. 1).
  • the second metal fine particle includes a second metal component that is a noble metal having no magnetism. Furthermore, the rare earth-containing material and the ceramic fine particle have no magnetism. Therefore, the second metal fine particle, the rare earth-containing material, and the ceramic fine particle are separated as non-magnetic materials by magnetic separation.
  • the second separated material is removed from the post-sintering waste, and the first separated material containing the first metal fine particles can be separated and recovered as the first metal component.
  • the first metal fine particles are finely divided Ni (first metal component) in a sintered state that constitutes the internal electrode layer 16.
  • the separation and recovery of the first metal component includes not only the separation and recovery of the first metal component itself, but also the separation and recovery of the first separated material containing the first metal fine particles as the first metal component.
  • the first metal component includes the first metal atom itself, a first metal component compound which is a reaction product of the first metal atom chemically reacting with other atoms, a solution of the first metal atom, a solution of the first metal component compound, and the like.
  • the state of the first metal component may be any of a liquid state, a solid state, and a mixed state of liquid and solid.
  • the first metal component may be any of an amorphous state, a crystalline state, and a mixed state of amorphous and crystalline.
  • this magnetic separation makes it possible to separate and recover the second metal fine particles and rare earth-containing material from the post-sintering waste after removing the first separated material.
  • step (B) it is preferable to mix and disperse the post-calcination waste after it has been pulverized in step (B) with an aqueous solvent such as water to create a mixed state, and then separate it using a magnet.
  • an aqueous solvent such as water
  • step (C) When the finely divided calcined waste is mixed with an aqueous solvent to form a mixed state, i.e., a slurry state, the ceramic fine particles, rare earth-containing material, first metal fine particles, and second metal fine particles contained in the finely divided calcined waste can be dispersed. Therefore, in step (C), the first separated material and the second separated material can be easily separated using a magnet.
  • the first separated material and the second separated material tend to be less dispersed than when in a slurry state. Therefore, for example, when the first separated material is attracted to a magnet, the second separated material is caught in the first separated material and attracted to the magnet, making it difficult to separate the first separated material and the second separated material.
  • the second separated product separated and recovered in step (C) is dissolved in a mineral acid having no oxidizing power.
  • a rare earth component-containing solution to be generated in which the rare earth components in the rare earth-containing material contained in the second separated product are dissolved.
  • the rare earth component-containing solution can be separated and recovered as a rare earth component.
  • the ceramic fine particles and the second metal fine particles in the second separated product are precipitated. The ceramic fine particles react with the mineral acid having no oxidizing power to become undissolved and precipitate.
  • the second metal fine particles such as Cu have a smaller ionization tendency than the hydrogen ions contained in the mineral acid having no oxidizing power, and therefore do not dissolve in the mineral acid having no oxidizing power.
  • the mineral acid having no oxidizing power is, for example, at least one selected from the group including dilute sulfuric acid and hydrochloric acid.
  • the rare earth components are separated and recovered as a rare earth component-containing solution.
  • the separation and recovery of rare earth components includes not only the separation and recovery of the rare earth components themselves, but also the separation and recovery of the rare earth component-containing solution as rare earth components.
  • the rare earth components include rare earth atoms themselves, rare earth component compounds which are reaction products of rare earth atoms chemically reacting with other atoms, solutions of rare earth atoms, solutions of rare earth component compounds, etc.
  • the state of the rare earth components may be any of a liquid state, a solid state, or a mixed state of liquid and solid.
  • the rare earth components may be any of an amorphous state, a crystalline state, or a mixed state of amorphous and crystalline.
  • step (D) it is preferable to adjust the pH of the rare earth component-containing solution to 1.5 or more and 2.5 or less by adding a mineral acid that has no oxidizing power.
  • step (D) by adjusting the rare earth component-containing solution to a pH of 1.5 or more and 2.5 or less using a mineral acid with no oxidizing power, it is possible to dissolve mainly the rare earth components in the rare earth-containing material in the mineral acid with no oxidizing power. Furthermore, if the pH is adjusted to a stronger acid than the above range, ceramic fine particles and the like may dissolve in the mineral acid with no oxidizing power, so it is preferable to adjust the pH to within the above range. More preferably, the rare earth component-containing solution is adjusted to a pH of 2 by adding a mineral acid with no oxidizing power.
  • the separated second separated material is in a slurry state with a pH of about 7.
  • a mineral acid with no oxidizing power to this slurry, it is also possible to produce a rare earth component-containing solution adjusted to a pH of 1.5 or more and 2.5 or less.
  • the second separated material after magnetic separation does not need to be in a slurry state and may be in a dry state.
  • the ceramic fine particles contained in the second separated product are, for example, BaTiO 3
  • dilute sulfuric acid is preferably used.
  • insoluble BaSO 4 is formed on the surface of the ceramic fine particles, which are BaTiO 3 , so that the ceramic fine particles can be precipitated.
  • the second metal fine particles, such as Cu do not dissolve in the mineral acid having no oxidizing power because they have a smaller ionization tendency than the hydrogen ions contained in the mineral acid having no oxidizing power.
  • rare earth powder can be dissolved in dilute sulfuric acid.
  • the rare earth-containing material such as Dy 2 O 3
  • the ceramic fine particles which are BaTiO 3
  • Dy in which the rare earth-containing material is dissolved in dilute sulfuric acid
  • a dysprosium sulfate (Dy 2 (SO 4 ) 3 ) solution in which Dy in the rare earth-containing material is dissolved in dilute sulfuric acid is generated as a rare earth component-containing solution.
  • hydrochloric acid or the like can be used as the mineral acid having no oxidizing power.
  • soluble BaCl 2 is formed on the surface of the ceramic fine particles, BaTiO 3. Therefore, it is preferable to accurately adjust the pH of hydrochloric acid or the like so as to precipitate the ceramic fine particles and dissolve the rare earth-containing material while not dissolving the second metal fine particles.
  • the rare earth component-containing solution containing the precipitated ceramic fine particles and the undissolved second metal fine particles produced in step (D) is filtered to separate the undissolved ceramic fine particles and the second metal fine particles from the rare earth component-containing solution. This solid-liquid separation allows the rare earth component-containing solution from which the undissolved ceramic fine particles and the second metal fine particles have been removed to be separated and recovered as rare earth components.
  • step (D) BaTiO3 is precipitated, and second metal fine particles such as Cu are not dissolved, and a dysprosium sulfate (Dy2( SO4 ) 3 ) solution in which Dy is dissolved in dilute sulfuric acid is generated as a rare earth component- containing solution.
  • the dysprosium sulfate solution from which BaTiO3 and Cu have been removed can be separated and recovered as rare earth components by the filtration in step (F).
  • Filtration can be performed using filter paper (filter cloth). It is preferable that the mesh size of the filter paper (filter cloth) is such that the undissolved ceramic microparticles and the second metal microparticles do not pass through the filter paper (filter cloth).
  • the rare earth component-containing solution containing the undissolved ceramic fine particles and the second metal fine particles produced in step (D) can be separated into solid and liquid, and the solid-liquid separation is not limited to filtration, but can be performed by any known method appropriately selected, such as decantation or centrifugation. Filtration is more preferable.
  • the rare earth component-containing solution obtained in step (F) is neutralized to precipitate and recover the rare earth component.
  • the precipitated rare earth component is separated and recovered, for example, by filtering the neutralized rare earth component-containing solution.
  • the rare earth component is separated and recovered as a rare earth component compound (e.g., Dy(OH) 3 , etc.) by neutralization.
  • the separation and recovery of the rare earth component includes not only the separation and recovery of the rare earth component itself, but also the separation and recovery of the rare earth component compound, which is a reaction product of the rare earth component chemically reacted, as the rare earth component.
  • alkali is used for neutralization.
  • alkalis include sodium hydroxide and potassium hydroxide.
  • the rare earth components are recovered by adjusting the pH of the rare earth component-containing solution to between pH 6 and pH 9. This allows the precipitate resulting from the neutralization reaction to be efficiently separated and recovered as rare earth components. More preferably, the rare earth component-containing solution is adjusted to pH 8 by adding an alkali.
  • dysprosium hydroxide (Dy(OH) 3 ) is obtained as a rare earth component compound by neutralization with sodium hydroxide. That is, since the dysprosium sulfate solution is acidic, the rare earth component dysprosium can be precipitated as dysprosium hydroxide (Dy(OH) 3 ) by neutralizing with an alkali, and separated and recovered.
  • Dyprosium hydroxide (Dy(OH) 3 ) can be separated and recovered by filtering the solution obtained by neutralizing the dysprosium sulfate solution with an alkali. In addition to filtration, known methods such as decantation and centrifugation can be used.
  • the rare earth component-containing solution produced in the dissolution of the second separated product in step (D) may contain metal components that are contaminants. These metal components are, for example, Ti, Mn, Ni, etc.
  • an alkali is added to the rare earth component-containing solution to adjust the pH to, for example, from 3 to 5, preferably about pH 4, so that Ti, Mn, etc. can be separated and recovered.
  • Ti precipitates as, for example, Ti(OH) 4
  • Mn precipitates as, for example, Mn(OH) 2. Therefore, the rare earth component-containing solution adjusted to about pH 4 is filtered to recover Ti(OH) 4 , Mn(OH) 2 , etc.
  • the rare earth components are separated and recovered by adding an alkali to the solution containing the rare earth components from which Ti, Mn, etc. have been separated and adjusted to a pH of 6 or more and 9 or less, preferably about pH 8, as described above.
  • Ni and the like can be separated and recovered by adding an alkali to the solution from which Ti, Mn, rare earth components, etc. have been separated, for example, to a pH of more than 9 to a pH of 11 or less, preferably about pH 10.
  • Ni precipitates as, for example, Ni(OH) 2 .
  • the solution adjusted to about pH 10 is filtered to recover Ni(OH) 2 and the like.
  • the rare earth component-containing solution is neutralized to a pH of 3 or more and a pH of 5 or less, preferably about pH 4, before the rare earth components are separated. Therefore, it is possible to first remove contaminants such as Ti and Mn from the rare earth component-containing solution. Since contaminants such as Ti and Mn have been removed from the rare earth component-containing solution in this way, it is possible to further facilitate separation of the rare earth components using the rare earth component-containing solution from which these contaminants have been removed.
  • step (E) the ceramic fine particles and the second metal fine particles extracted by filtration in step (F) are dissolved in ammonia water. This produces a second metal solution in which the second metal component contained in the second metal fine particles is dissolved. Thus, the second metal solution can be separated and recovered as the second metal component. At this time, the ceramic fine particles are precipitated.
  • a second metal fine particle containing a second metal component such as Cu and a ceramic fine particle of BaTiO3 are dissolved in ammonia water, thereby obtaining a second metal solution containing an ammine copper complex such as [Cu( NH3 ) 4 ] 2+ .
  • BaTiO3 precipitates in the second metal solution.
  • the second metal component is separated and recovered as a second metal solution.
  • the separation and recovery of the second metal component includes not only the separation and recovery of the second metal component itself, but also the separation and recovery of the second metal component solution as the second metal component.
  • the second metal component includes the second metal component itself, a second metal component compound which is a reaction product of the second metal component chemically reacting with other atoms, a solution of the second metal component, a solution of the second metal component compound, and the like.
  • the state of the second metal component may be any of a liquid state, a solid state, and a mixed state of liquid and solid.
  • the second metal component may be any of an amorphous state, a crystalline state, and a mixed state of amorphous and crystalline.
  • step (E) it is preferable to adjust the second metal solution to a pH of 9 or more and a pH of 10 or less by adding ammonia water.
  • the second metal solution can be efficiently separated and recovered as the second metal component. More preferably, the second metal solution is adjusted to a pH of 9.5 by adding ammonia water.
  • an ammonium salt such as ammonium sulfate to the ammonia water.
  • the ammonia water is a source of ammonia for forming the second metal component such as Cu as an ammine complex such as a copper ammine complex.
  • the ammonium salt provides a counter ion to the ammine complex such as the copper ammine complex.
  • an ammonium salt such as ammonium sulfate supplies SO 4 2- as a counter ion to the copper ammine complex which is [Cu(NH 3 ) 4 ] 2+ .
  • the concentration of ammonia decreases, it forms a salt such as CuSO 4 to suppress the precipitation of Cu ions.
  • the second metal solution containing the precipitated ceramic fine particles produced in step (E) is filtered to separate the precipitated ceramic fine particles from the second metal solution.
  • the second metal solution from which the precipitated ceramic fine particles have been removed can be separated and recovered as a second metal component from the second metal solution containing the precipitated ceramic fine particles.
  • step (E) a second metal solution is generated in which a second metal component such as Cu is dissolved in ammonia water while BaTiO3 is precipitated.
  • the second metal solution contains a copper ammine complex such as [Cu( NH3 ) 4 ] 2+ .
  • the second metal solution containing the copper ammine complex from which BaTiO3 has been removed can be separated and recovered as the second metal component by filtration in step (H).
  • Filtration can be performed using filter paper (filter cloth).
  • the mesh size of the filter paper (filter cloth) is preferably such that the precipitated ceramic fine particles do not pass through the filter paper (filter cloth).
  • the solid-liquid separation of the second metal solution containing the precipitated ceramic fine particles produced in step (E) need only be performed, and the solid-liquid separation is not limited to filtration, and can be performed by any known method appropriately selected, such as decantation or centrifugation. Filtration is more preferable.
  • the first separated product separated and recovered in step (C) is dissolved in a mineral acid.
  • the first separated product includes a first metal fine product and a ceramic fine product.
  • the ceramic fine product contained in the first separated product is precipitated as an undissolved product, and a first metal solution in which the first metal fine product in the first separated product is dissolved is generated.
  • the first metal component contained in the first metal fine product is separated and recovered as a first metal solution.
  • the separation and recovery of the first metal component includes not only the separation and recovery of the first metal component itself, but also the separation and recovery of the first metal solution as the first metal component.
  • the mineral acid is, for example, at least one selected from the group including sulfuric acid, nitric acid, and hydrochloric acid.
  • the mineral acid may be either a mineral acid that does not have oxidizing power or a mineral acid that has oxidizing power.
  • when simply saying mineral acid it is meant to include both a mineral acid that does not have oxidizing power and a mineral acid that has oxidizing power.
  • step (I) it is preferable to adjust the pH of the first metal solution to 1.5 or more and 2.5 or less by adding a mineral acid.
  • the first metal solution is adjusted to a pH of 1.5 or more and 2.5 or less using a mineral acid, so that the first metal component in the first metal microparticles can be dissolved in the mineral acid.
  • the pH is adjusted to a stronger acid than the above range, the ceramic microparticles and the like may dissolve in the mineral acid, so it is preferable to adjust the pH to within the above range. More preferably, the first metal solution is adjusted to a pH of 2 by adding a mineral acid.
  • the separated first separated material is in a slurry state with a pH of about 7.
  • a first metal solution adjusted to a pH of 1.5 or more and 2.5 or less can be produced.
  • the first separated material after magnetic separation does not need to be in a slurry state and may be in a dry state.
  • the ceramic fine particles contained in the first separation product are, for example, BaTiO 3
  • sulfuric acid it is preferable to use sulfuric acid.
  • insoluble BaSO 4 is formed on the surface of the ceramic fine particles, which are BaTiO 3 , so that the ceramic fine particles can be precipitated.
  • the first metal fine particles, such as Ni can be dissolved in sulfuric acid.
  • the first separation product which mainly contains the first metal fine particles, Ni and the ceramic fine particles, which are BaTiO 3 , in sulfuric acid
  • BaTiO 3 is precipitated, and a nickel sulfate (NiSO 4 ) solution in which Ni is dissolved in sulfuric acid is generated as the first metal solution.
  • NiSO 4 nickel sulfate
  • hydrochloric acid or the like can be used as the mineral acid other than sulfuric acid.
  • hydrochloric acid when hydrochloric acid is used as the mineral acid, soluble BaCl2 is formed on the surface of BaTiO3 , which is the ceramic fine particle. Therefore, it is preferable to precisely adjust the pH of hydrochloric acid or the like so as to precipitate the ceramic fine particle and dissolve the first metal fine particle.
  • the first metal solution containing the precipitated ceramic fine particles produced in step (I) is filtered to separate the precipitated ceramic fine particles from the first metal solution.
  • the first metal solution from which the precipitated ceramic fine particles have been removed can be separated and recovered as a first metal component from the first metal solution containing the precipitated ceramic fine particles.
  • step (I) BaTiO3 is precipitated and a nickel sulfate ( NiSO4 ) solution in which Ni is dissolved in sulfuric acid is generated as the first metal solution.
  • NiSO4 nickel sulfate
  • the nickel sulfate solution from which BaTiO3 has been removed can be obtained by filtration.
  • Filtration can be performed using filter paper (filter cloth).
  • the mesh size of the filter paper (filter cloth) is preferably such that the precipitated ceramic fine particles do not pass through the filter paper (filter cloth).
  • the solid-liquid separation of the first metal solution containing the precipitated ceramic fine particles produced in step (I) need only be performed, and is not limited to solid-liquid separation by filtration, and solid-liquid separation can be performed by an appropriate selection from known methods such as decantation and centrifugation. Filtration is more preferable.
  • the separation and recovery of the first metal component includes not only the separation and recovery of the first metal component itself, but also the separation and recovery of the first metal component compound, which is a reaction product of the chemical reaction of the first metal component, as the first metal component.
  • the first metal component constituting the internal electrode layer 16, the second metal component constituting the external electrode 30, and the rare earth component contained in the ceramic layer 14 can be separated and recovered from the fired waste of the multilayer ceramic capacitor. The details are explained below.
  • the inventors of the present application have considered the effective use of various components contained in waste after firing of a multilayer ceramic capacitor (firing for firing electrode layers).
  • various components are in a sintered state due to the firing process.
  • the internal electrode layer is formed including first metal particles (first metal sintered body) obtained by sintering a first metal powder such as Ni by firing.
  • the ceramic layer is formed including ceramic particles (ceramic sintered body) obtained by sintering a ceramic powder such as BaTiO 3 by firing.
  • the external electrode is formed including second metal particles (second metal sintered body) obtained by sintering a second metal powder such as Cu by firing.
  • the post-sintered waste after pulverization can be separated into a first separated material and a second separated material by separating the finely pulverized post-sintered waste using a magnet in step (C).
  • the first separated material includes the ceramic microparticles and the first metal microparticles.
  • the second separated material includes the ceramic microparticles, rare earth-containing materials, and second metal microparticles. Therefore, by separating and recovering the first separated material in step (C), it is possible to remove the second separated material from the post-sintered waste, and to separate and recover the first separated material including the first metal microparticles as the first metal component.
  • step (D) the second separated material is dissolved in a mineral acid that has no oxidizing power, thereby producing a rare earth component-containing solution in which the rare earth components in the rare earth powder-containing material are dissolved.
  • a rare earth component-containing solution in which the rare earth components in the rare earth powder-containing material are dissolved.
  • the ceramic fine particles and the second metal fine particles in the second separated material have precipitated.
  • the ceramic fine particles react with the mineral acid that has no oxidizing power, and become undissolved and precipitate.
  • the second metal fine particles, such as Cu do not dissolve in the mineral acid that has no oxidizing power, because they have a smaller ionization tendency than the hydrogen ions contained in the mineral acid that has no oxidizing power.
  • a second metal solution can be produced in which the second metal components, such as Cu, in the second metal fine particles are dissolved. This makes it possible to separate and recover the second metal components from the second metal solution. At this time, the ceramic fine particles in the second separated product do not dissolve in the ammonia water but precipitate.
  • the rare earth components can be separated and recovered as a rare earth component-containing solution from the post-firing waste after micronization, and the second metal solution can be separated and recovered as a second metal component. Then, in the process of going through each step, the ratio of the rare earth components in the material containing the rare earth components and the ratio of the second metal components in the material containing the second metal components increase. Therefore, for example, rare earth components such as Dy and second metal components such as Cu can be recovered at high quality.
  • the separation and recovery method of the above embodiment further includes step (I).
  • step (I) the first separated material is dissolved in a mineral acid to produce a first metal solution in which the first metal component contained in the first metal fine particles is dissolved.
  • step (I) the ceramic fine particles contained in the first separated material react with the mineral acid to become undissolved and precipitate, so that the ceramic fine particles and the first metal component contained in the first separated material are separated.
  • the first metal solution can be separated and recovered as the first metal component from the post-firing waste after micronization. And, as each step goes through, the proportion of the first metal component in the material containing the first metal component increases. Therefore, the first metal component, such as Ni, can be recovered in high quality.
  • the first metal component, second metal component, rare earth component, etc. are separated and recovered from the fired waste of multilayer ceramic capacitors, so the fired waste is not discarded as waste but can be used as a resource, reducing the burden on the environment.
  • Example 10 g of the fired waste was prepared.
  • the 10 g of fired waste contained 35 mass % (3.5 g) of Ni, which is the first metal component, 7 mass % (0.7 g) of Cu, which is the second metal component, 54 mass % (5.4 g) of ceramic particles (ceramic sintered body) which is BaTiO 3 , 2 mass % (0.2 g) of Dy, which is a rare earth component, and 2 mass % (0.2 g) of contaminants such as Mg, Mn, and SiO 2 (step (A)).
  • the fired waste was pulverized and finely divided (step (B)).
  • the fired waste after pulverization and finely divided was mixed with 100 ml of water to prepare a slurry.
  • the slurry was magnetically separated using a magnet.
  • 4.5 g of the first separated product was separated and recovered, and 4.6 g of the second separated product was separated and recovered (step (C)).
  • 100 ml of water was added to 4.6 g of the second separated product, and 1 mol% sulfuric acid was added little by little to adjust the pH to 2.
  • the ceramic fine particles (BaTiO 3 ) and the second metal fine particles (Cu) in the second separated product were precipitated, and the Dy contained in the rare earth-containing material was dissolved in the sulfuric acid solution (step (D)).
  • step (F) 100 ml of water and 2 g of ammonium sulfate were added to 4.1 g of the filtrate of the ceramic fine particles (BaTiO 3 ) and the second metal fine particles (Cu) recovered in step (F), and 1 mol% ammonia water was added little by little to adjust the pH to 9.5. This caused the ceramic fine particles (BaTiO 3 ) to precipitate, and the second metal fine particles (Cu) to dissolve in ammonia water (step (E)). This solution was filtered to separate and recover 90 ml of ammine copper complexes such as [Cu(NH 3 ) 4 ] 2+ . Thus, by passing through this step, approximately 60% of the Cu contained in the waste after firing was recovered.
  • step (J) 100 ml of water was added to 4.5 g of the first separated product recovered in step (C), and 1 mol % sulfuric acid was added little by little to adjust the pH to 2.
  • the ceramic fine particles (BaTiO 3 ) in the first separated product were precipitated, and the first metal fine particles (Ni) were dissolved in the sulfuric acid solution (step (I)).
  • the solution in which the ceramic fine particles (BaTiO 3 ) were precipitated and the first metal fine particles (Ni) were dissolved in the sulfuric acid solution was filtered to obtain 90 ml of nickel sulfate (Ni(SO 4 )) solution (step (J)).
  • the separation and recovery method according to the present embodiment uses fired multilayer ceramic capacitor waste as a starting material, and by going through processes such as magnetic separation and leaching by neutralization, it is possible to easily separate and refine high-quality rare earth components such as Dy, Ni, and Cu, a first metal component, and a second metal component.
  • the external electrode 30 includes a fired electrode layer 32.
  • the fired electrode layer 32 is the outermost layer of the multilayer ceramic capacitor 10 (FIG. 3).
  • the form of the external electrode 30 is not limited to this.
  • the external electrode 30 includes a fired electrode layer 32 and a plating layer.
  • the plating layer is the outermost layer of the multilayer ceramic capacitor. Descriptions of the same content as in the first embodiment will be omitted or simplified.
  • FIG. 7 is a cross-sectional view (1) parallel to a plane including the length direction and stacking direction of a multilayer ceramic capacitor according to a second embodiment of the present invention.
  • FIG. 8 is a cross-sectional view (2) parallel to a plane including the length direction and stacking direction of another type of multilayer ceramic capacitor according to the second embodiment of the present invention.
  • the multilayer ceramic capacitors 10A (FIG. 7) and 10B (FIG. 8) according to the second embodiment include a laminate 12 similar to that of the first embodiment, and further include an external electrode 30 arranged on the laminate 12.
  • the external electrode 30 includes a baked electrode layer 32 and a plating layer 34 arranged on the baked electrode layer 32.
  • the plating layer 34 is the outermost layer of the multilayer ceramic capacitors 10A and 10B.
  • the configuration other than the plating layer 34 is the same as that of the first embodiment.
  • the plating layer 34 is formed by including at least one selected from, for example, Ni, Sn, Cu, Ag, etc. Note that the multilayer ceramic capacitor 10 according to the first embodiment does not include a plating layer (FIG. 3).
  • the multilayer ceramic capacitors 10A and 10B according to the second embodiment are formed through the steps (step 1) to (step 7) of the first embodiment described above, followed by a step (step 8) of disposing a plating layer 34 on the baked electrode layer 32.
  • a plating process is performed to form a first plating layer 34a (first lower plating layer 34a 1 , first upper plating layer 34a 2 ) on the first baked electrode layer 32a, and a second plating layer 34b (second lower plating layer 34b 1 , second upper plating layer 34b 2 ) on the second baked electrode layer 32b.
  • the plating layer 34 is formed, for example, by barrel plating. Either electrolytic plating or electroless plating may be used for the plating process.
  • electroless plating has the disadvantage that a pretreatment using a catalyst or the like is required to improve the plating deposition speed, which complicates the process. Therefore, it is usually preferable to use electrolytic plating.
  • the multilayer ceramic capacitors 10A and 10B having the plating layer 34 according to the second embodiment are also included in the post-sintering (sintering for fired electrode layers) waste, similar to the multilayer ceramic capacitor 10 according to the first embodiment (sometimes called the multilayer ceramic capacitor 10 without the plating layer 34).
  • the multilayer ceramic capacitors 10A and 10B having the plating layer 34 may be introduced into the separation and recovery method shown in FIG. 1 described above, or into the separation and recovery method shown in FIG. 9 described below.
  • the separation and recovery method in FIG. 1 does not include a step of removing the plating layer 34, but the separation and recovery method in FIG. 9 includes a step of removing the plating layer 34 (step (K)).
  • the plating layer 34 may be formed from a single plating layer (FIG. 7) or may be formed by stacking multiple plating layers (FIG. 8).
  • FIG. 7 we will explain a multilayer ceramic capacitor 10A in which the plating layer 34 is a single plating layer, and a multilayer ceramic capacitor 10B in which the plating layer 34 is a multiple plating layer.
  • an external electrode 30 includes a baked electrode layer 32 and a plating layer 34 disposed on the baked electrode layer 32.
  • the plating layer 34 is formed of a single-layer plating layer.
  • the plating layer 34 includes a first lower-layer plating layer (first first-stage plating layer) 34a 1 and a second lower-layer plating layer 34b 1 (second first-stage plating layer).
  • the first external electrode 30a includes a first baked electrode layer 32a and a first lower-layer plating layer 34a 1 on the first baked electrode layer 32a.
  • the second external electrode 30b includes a second baked electrode layer 32b and a second lower-layer plating layer 34b 1 on the second baked electrode layer 32b.
  • the first and second lower plating layers 34a1 , 34b1 are the outermost layers among the layers disposed on the laminate 12.
  • the baked electrode layer 32 serves as a base for the plating layer 34, and is therefore sometimes referred to as a base electrode layer.
  • the multilayer ceramic capacitor 10A having the plating layer 34 is included in the post-sintering waste (sintering for the fired electrode layer) as in the first embodiment. Therefore, the multilayer ceramic capacitor 10A having the plating layer 34 can be input to the separation and recovery method of FIG. 1 described in the first embodiment. That is, in the preparation of the post-sintering waste in step (A), the multilayer ceramic capacitor 10A having the plating layer 34 can be prepared as the post-sintering waste. Thereafter, the first metal component, the second metal component, and the rare earth component can be separated and recovered from the multilayer ceramic capacitor 10A having the plating layer 34 by going through the separation and recovery method described in FIG. 1.
  • FIG. 9 is a flow diagram showing a method for separating and recovering rare earth components and metal components from waste after firing of a multilayer ceramic capacitor (firing for firing electrode layers), including a plating removal step.
  • the separation and recovery method of FIG. 9 includes a plating removal step (K) for removing the plating layer 34 between the preparation of the post-firing waste in step (A) and the refining in step (B), as compared to the separation and recovery method of FIG. 1.
  • the separation and recovery method of FIG. 9 is the same as the separation and recovery method of FIG. 1, except for the inclusion of step (K).
  • the method of separation and recovery shown in FIG. 1, which does not include a plating removal step, or the method of separation and recovery shown in FIG. 9, which includes a plating removal step can be used, for example, as follows:
  • the metal components contained in both the first and second lower plating layers 34a 1 , 34b 1 are the same as at least one of the first metal component contained in the internal electrode layer 16 and the second metal component contained in the fired electrode layer 32.
  • the laminated ceramic capacitor 10A having the plating layer 34 is prepared as a waste product after firing in step (A) of FIG. 1, and is further treated in each step after step (B) of the separation and recovery method shown in FIG. 1.
  • the first metal component of the plating layer 34 can be separated and recovered together with the first metal component contained in the internal electrode layer 16.
  • the second metal component of the plating layer 34 can be separated and recovered together with the second metal component contained in the baked electrode layer 32. It is possible to separate and recover the rare earth component from the ceramic layer 14.
  • both the first and second lower plating layers 34a 1 and 34b 1 are plating layers mainly composed of Ni. It is also assumed that the internal electrode layer 16 contains Ni as the first metal component.
  • the multilayer ceramic capacitor 10A is prepared as a post-sintering waste in step (A) of FIG. 1 without removing the first and second lower plating layers 34a 1 and 34b 1. Thereafter, by going through each step from step (B) onward in the separation and recovery method of FIG. 1, it is possible to separate and recover Ni, which is the first metal component, from the first and second lower plating layers 34a 1 and 34b 1 and the internal electrode layer 16. It is possible to separate and recover the second metal component from the fired electrode layer 32, and the rare earth component from the ceramic layer 14.
  • both the first and second lower plating layers 34a 1 and 34b 1 are plating layers mainly composed of Cu.
  • the baked electrode layer 32 contains Cu as the second metal component.
  • the multilayer ceramic capacitor 10A is prepared as waste after firing in step (A) of FIG. 1 without removing the first and second lower plating layers 34a 1 and 34b 1.
  • the second metal component, Cu can be separated and recovered from the first and second lower plating layers 34a 1 and 34b 1 and the baked electrode layer 32.
  • the first metal component can be separated and recovered from the internal electrode layer 16, and the rare earth component can be separated and recovered from the ceramic layer 14.
  • the metal components contained in both the first and second lower plating layers 34a 1 and 34b 1 are different from both the first metal component contained in the internal electrode layer 16 and the second metal component contained in the fired electrode layer 32.
  • the metal component (third metal component) contained in the first and second lower plating layers 34a 1 and 34b 1 is different from both the first metal component and the second metal component.
  • the multilayer ceramic capacitor 10A having the plating layer 34 is prepared as a post-sintering waste in step (A) of FIG. 9. Then, the first and second lower plating layers 34a 1 and 34b 1 are removed by plating removal in step (K).
  • the multilayer ceramic capacitor 10A from which the plating layer 34 has been removed is further processed by each step after step (B) of the separation and recovery method shown in FIG. 9. This makes it possible to separate and recover the first metal component constituting the internal electrode layer 16, the second metal component constituting the fired electrode layer 32, and the rare earth component contained in the ceramic layer 14 from the multilayer ceramic capacitor 10A from which the plating layer 34 has been removed.
  • both the first and second lower plating layers 34a 1 and 34b 1 are plating layers mainly composed of Sn (an example of a third metal component). It is also assumed that the internal electrode layer 16 contains Ni as the first metal component, and the fired electrode layer 32 contains Cu as the second metal component.
  • the multilayer ceramic capacitor 10A having the plating layer 34 is prepared as waste after firing in step (A) of FIG. 9. Then, in step (K) of FIG. 9, the first and second lower plating layers 34a 1 and 34b 1 mainly composed of Sn are removed.
  • the first and second lower plating layers 34a 1 and 34b 1 mainly composed of Sn can be removed by immersing the multilayer ceramic capacitor 10A having the plating layer 34 in an alkaline solution other than ammonia water, such as sodium hydroxide and potassium hydroxide.
  • an alkaline solution other than ammonia water such as sodium hydroxide and potassium hydroxide.
  • the baked electrode layer 32 mainly composed of Cu is exposed to the alkaline solution by removing the plating layer 34.
  • the baked electrode layer 32 mainly composed of Cu is not easily corroded by the alkaline solution.
  • the alkaline solution other than ammonia water is adjusted to, for example, about pH 12.
  • step (B) of the separation and recovery method of Figure 9 Thereafter, by going through each step from step (B) of the separation and recovery method of Figure 9 onwards, the first metal component constituting the internal electrode layer 16, the second metal component constituting the baked electrode layer 32, and the rare earth component contained in the ceramic layer 14 can be separated and recovered.
  • the plating layer 34 which is mainly composed of Sn
  • the plating layer 34 is removed with an alkaline solution other than ammonia water.
  • the plating layer 34 which is mainly composed of Sn
  • the baked electrode layer 32 which is mainly composed of Cu
  • the acidic solution is adjusted to, for example, about pH 2.
  • the multilayer ceramic capacitor 10A having the plating layer 34 may be prepared as waste after firing in step (A) of Fig. 9. Then, the first and second lower plating layers 34a1 , 34b1 may be removed by plating removal in step (K).
  • both the first and second lower plating layers 34a 1 and 34b 1 are plating layers mainly composed of Ni. It is also assumed that the internal electrode layer 16 contains Ni as the first metal component, and the baked electrode layer 32 contains Cu as the second metal component.
  • the multilayer ceramic capacitor 10A having the plating layer 34 is prepared as waste after firing in step (A) of FIG. 9. Then, in step (K) of FIG. 9, the first and second lower plating layers 34a 1 and 34b 1 mainly composed of Ni are removed.
  • the first and second lower plating layers 34a 1 and 34b 1 mainly composed of Ni can be removed by immersing the multilayer ceramic capacitor 10A having the plating layer 34 in an acidic solution that does not have oxidizing power, such as hydrochloric acid and dilute sulfuric acid.
  • the baked electrode layer 32 mainly composed of Cu is exposed to the acidic solution by removing the plating layer 34.
  • the baked electrode layer 32 which is mainly composed of Cu, is not easily corroded by the acidic solution.
  • the acidic solution is adjusted to, for example, a pH of about 2.
  • the first metal component constituting the internal electrode layer 16, the second metal component constituting the baked electrode layer 32, and the rare earth component contained in the ceramic layer 14 can be separated and recovered.
  • an external electrode 30 includes a baked electrode layer 32 and a plating layer 34 disposed on the baked electrode layer 32.
  • the plating layer 34 is formed of multiple plating layers.
  • the plating layer 34 is formed of two plating layers.
  • the plating layer 34 includes a first lower plating layer (first first-stage plating layer) 34a1 and a second lower plating layer (second first-stage plating layer) 34b1 , a first upper plating layer (first second-stage plating layer) 34a2 and a second upper plating layer (second second-stage plating layer) 34b2 .
  • the first external electrode 30a includes a first baked electrode layer 32a, a first lower-layer plating layer 34a1 on the first baked electrode layer 32a, and a first upper-layer plating layer 34a2 on the first lower-layer plating layer 34a1 .
  • the second external electrode 30b includes a second baked electrode layer 32b, a second lower-layer plating layer 34b1 on the second baked electrode layer 32b , and a second upper-layer plating layer 34b2 on the second lower-layer plating layer 34b1 .
  • the first upper-layer plating layer 34a2 and the second upper-layer plating layer 34b2 are the outermost layers among the layers arranged on the laminate 12.
  • the multilayer ceramic capacitor 10B having the plating layer 34 is formed through the steps (step 1) to (step 7) of the first embodiment described above, followed by a step (step 8) of disposing the plating layer 34 on the baked electrode layer 32.
  • step 8 a plating process is performed to sequentially form a first lower-layer plating layer 34a1 and a first upper-layer plating layer 34a2 on the first baked electrode layer 32a, and a second upper-layer plating layer 34b2 on the second lower-layer plating layer 34b1 on the second baked electrode layer 32b .
  • the multilayer ceramic capacitor 10B having the plating layer 34 is included in the post-sintering waste (sintering for the fired electrode layer) as in the first embodiment. Therefore, the multilayer ceramic capacitor 10B having the plating layer 34 can be input to the separation and recovery method of FIG. 1 described in the first embodiment. That is, in the preparation of the post-sintering waste in step (A), the multilayer ceramic capacitor 10B having the plating layer 34 can be prepared as the post-sintering waste. Thereafter, the first metal component, the second metal component, and the rare earth component can be separated and recovered from the multilayer ceramic capacitor 10B having the plating layer 34 by going through the separation and recovery method described in FIG. 1.
  • the method of separation and recovery shown in FIG. 1, which does not include a plating removal step, or the method of separation and recovery shown in FIG. 9, which includes a plating removal step can be used, for example, as follows:
  • the metal components contained in the first and second lower plating layers 34a 1 , 34b 1 and the first and second upper plating layers 34a 2 , 34b 2 are the same as at least one of the first metal component contained in the internal electrode layer 16 and the second metal component contained in the baked electrode layer 32.
  • the laminated ceramic capacitor 10B having the plating layer 34 is prepared as waste after firing in step (A) of FIG. 1, and is treated by the separation and recovery method shown in FIG. 1.
  • the metal components of the first and second lower plating layers 34a 1 , 34b 1 may be the same as the first metal component contained in the internal electrode layer 16.
  • the metal components of the first and second upper plating layers 34a 2 , 34b 2 may be the same as the second metal component contained in the baked electrode layer 32.
  • the metal components of the first and second lower plating layers 34a1 , 34b1 may be the same as the second metal component contained in the baked electrode layer 32.
  • the metal components of the first and second upper plating layers 34a2 , 34b2 may be the same as the first metal component contained in the internal electrode layer 16.
  • the first and second metal components of the plating layer 34 can be separated and recovered together with the first metal component contained in the internal electrode layer 16 and the second metal component contained in the baked electrode layer 32. It is to be noted that rare earth components can be separated and recovered from the ceramic layer 14.
  • the first and second lower plating layers 34a1 , 34b1 are plating layers mainly composed of Ni (or Cu).
  • the first and second upper plating layers 34a2 , 34b2 are plating layers mainly composed of Cu (or Ni).
  • the internal electrode layer 16 contains Ni as a first metal component.
  • the baked electrode layer 32 contains Cu as a second metal component.
  • the multilayer ceramic capacitor 10B is prepared as waste after firing in step (A) of FIG. 1 without removing the first and second lower plating layers 34a1 , 34b1 and the first and second upper plating layers 34a2 , 34b2 .
  • the first metal component Ni and the second metal component Cu can be separated and recovered from the first and second lower plating layers 34a1 , 34b1 and the first and second upper plating layers 34a2 , 34b2 , the internal electrode layer 16, and the baked electrode layer 32.
  • Rare earth components can be separated and recovered from the ceramic layer 14.
  • step (K) the first and second lower plating layers 34a 1 , 34b 1 and the first and second upper plating layers 34a 2 , 34b 2 are removed by plating removal in step (K).
  • step (B) of the separation and recovery method shown in FIG. 9. This makes it possible to separate and recover the first metal component constituting the internal electrode layer 16, the second metal component constituting the fired electrode layer 32, and the rare earth component contained in the ceramic layer 14 from the multilayer ceramic capacitor 10B from which the plating layer 34 has been removed.
  • the (third metal component) contained in the first and second upper plating layers 34a 2 , 34b 2 is different from both the first metal component contained in the internal electrode layer 16 and the second metal component contained in the baked electrode layer 32.
  • the metal components contained in the first and second lower plating layers 34a 1 , 34b 1 are the same as either the first metal component contained in the internal electrode layer 16 or the second metal component contained in the baked electrode layer 32.
  • the laminated ceramic capacitor 10B having the plating layer 34 is prepared as waste after firing in step (A) of FIG. 9. Then, the first and second upper plating layers 34a 2 , 34b 2 are removed by plating removal in step (K).
  • the multilayer ceramic capacitor 10B from which the first and second upper plating layers 34a2 , 34b2 have been removed is further processed by each step subsequent to step (B) of the separation and recovery method shown in Fig. 9.
  • the metal components (first metal component or second metal component) contained in the first and second lower plating layers 34a1 , 34b1 , the first metal component constituting the internal electrode layer 16 , the second metal component constituting the fired electrode layer 32, and the rare earth components contained in the ceramic layer 14 can be separated and recovered from the multilayer ceramic capacitor 10B from which the first and second upper plating layers 34a2, 34b2 have been removed.
  • the metal component contained in the first and second upper plating layers 34a 2 , 34b 2 is a plating layer mainly composed of Sn (an example of a third metal component).
  • the metal component contained in the first and second lower plating layers 34a 1 , 34b 1 is a plating layer mainly composed of Ni (or Cu).
  • the internal electrode layer 16 contains Ni as the first metal component
  • the fired electrode layer 32 contains Cu as the second metal component.
  • the multilayer ceramic capacitor 10B having the plating layer 34 is prepared as waste after firing in step (A) of FIG. 9. Then, in step (K) of FIG.
  • the first and second upper plating layers 34a 2 , 34b 2 mainly composed of Sn are removed.
  • the first and second upper plating layers 34a 2 , 34b 2 mainly composed of Sn can be removed by immersing the laminated ceramic capacitor 10B having the plating layer 34 in an alkaline solution other than ammonia water, such as sodium hydroxide and potassium hydroxide.
  • the first and second lower plating layers 34a 1 , 34b 1 mainly composed of Ni (or Cu) are exposed to the alkaline solution by removing the first and second upper plating layers 34a 2 , 34b 2.
  • the first and second lower plating layers 34a 1 , 34b 1 mainly composed of Ni (or Cu ) are not easily corroded by the alkaline solution.
  • the baked electrode layer 32 mainly composed of Cu is also not easily corroded by the alkaline solution.
  • the alkaline solution other than ammonia water is adjusted to, for example, about pH 12. 9
  • the first metal component Ni and the second metal component Cu can be separated and recovered from the first and second lower plating layers 34a1 , 34b1 , the internal electrode layer 16, and the baked electrode layer 32.
  • Rare earth components can be separated and recovered from the ceramic layer 14.
  • the metal component contained in the first and second upper plating layers 34a 2 , 34b 2 is a plating layer mainly composed of Sn (an example of a third metal component).
  • the metal component contained in the first and second lower plating layers 34a 1 , 34b 1 is a plating layer mainly composed of Ni, not Cu.
  • the internal electrode layer 16 contains Ni as the first metal component
  • the fired electrode layer 32 contains Cu as the second metal component.
  • the multilayer ceramic capacitor 10B having the plating layer 34 is prepared as a post-sintering waste in the step (A) of FIG. 9. 9, the first and second upper plating layers 34a 2 , 34b 2 mainly composed of Sn and the first and second lower plating layers 34a 1 , 34b 1 mainly composed of Ni are removed.
  • the first and second upper plating layers 34a 2 , 34b 2 mainly composed of Sn and the first and second lower plating layers 34a 1 , 34b 1 mainly composed of Ni can be removed by immersing the laminated ceramic capacitor 10B having the plating layer 34 in an acidic solution that does not have oxidizing power , such as hydrochloric acid or dilute sulfuric acid.
  • the baked electrode layer 32 mainly composed of Cu is exposed to the acidic solution by removing the plating layer 34.
  • the baked electrode layer 32 mainly composed of Cu is not easily corroded by the acidic solution.
  • the acidic solution is adjusted to, for example, about pH 2. 9, the first metal component Ni and the second metal component Cu can be separated and recovered from the internal electrode layer 16 and the fired electrode layer 32.
  • the rare earth component can be separated and recovered from the ceramic layer 14.
  • the first and second upper plating layers 34a2 , 34b2 mainly composed of Sn and the first and second lower plating layers 34a1 , 34b1 mainly composed of Ni are removed at the same time by the non-oxidizing acidic solution. However, they may be removed in order.
  • the multilayer ceramic capacitor 10B is immersed in an alkaline solution (e.g., about pH 12) other than ammonia water, such as sodium hydroxide and potassium hydroxide, to remove the first and second upper plating layers 34a2 , 34b2 mainly composed of Sn.
  • an alkaline solution e.g., about pH 12
  • ammonia water such as sodium hydroxide and potassium hydroxide
  • the multilayer ceramic capacitor 10B is immersed in an acidic solution (e.g., about pH 2) other than ammonia water, such as hydrochloric acid and dilute sulfuric acid, to remove the first and second lower plating layers 34a1 , 34b1 mainly composed of Ni. 9, the first metal component Ni and the second metal component Cu can be separated and recovered from the internal electrode layer 16 and the fired electrode layer 32.
  • the rare earth component can be separated and recovered from the ceramic layer 14.
  • the first metal component constituting the internal electrode layer 16, the second metal component constituting the external electrode 30, and the rare earth component contained in the ceramic layer 14 can be separated and recovered by the separation and recovery method shown in Fig. 1 or 9. Furthermore, by employing a separation and recovery method suitable for separating and recovering the metal components from the plating layer 34, the first metal component and the second metal component can also be recovered from the plating layer 34 in some cases.
  • the calcination waste is pulverized and refined in step (B).
  • the calcination waste may be refined by dispersing it in a solvent (e.g., an aqueous solvent or other solvent) in addition to the refinement in step (B) (particularly, refinement by pulverization), or instead of the refinement in step (B) (particularly, refinement by pulverization), in the slurry state.
  • a solvent e.g., an aqueous solvent or other solvent
  • wet refinement the refinement in which the calcination waste is mixed with a solvent to form a slurry.
  • the refinement in which the calcination waste is pulverized in the slurry generated by mixing the calcination waste with a solvent is called wet grinding.
  • the aqueous solvent for example, water can be used.
  • the calcined waste after being pulverized in step (B) can be mixed with an aqueous solvent such as water and dispersed to form a slurry state.
  • an aqueous solvent such as water
  • the calcined waste in this slurry state can be magnetically separated in step (C). In other words, the effort of generating a slurry state in the magnetic separation in step (C) can be omitted.
  • the post-calcination waste into a slurry using an organic solvent.
  • a process for removing the organic solvent is required in the separation and recovery method. Therefore, it is preferable to make the post-calcination waste into a slurry using an aqueous solvent such as water.
  • the waste after firing is waste after firing for the fired electrode layer in (step 7).
  • the waste after firing is not limited to this.
  • the waste after firing may include waste that has not been fired for the fired electrode layer and has been fired before being input to the separation and recovery method of FIG. 1 and FIG. 9.
  • the firing is preferably performed at the firing temperature for the fired electrode layer.
  • Waste before firing for the baked electrode layer includes, for example, waste discharged in (step 1) to (step 6).
  • waste before firing for the baked electrode layer may include waste after the paste for the baked electrode layer is applied to the laminate 12 in (step 7) but before firing for the baked electrode layer.
  • waste before firing for the baked electrode layer includes, for example, waste of dielectric slurry and conductive paste for the internal electrode layer in (step 1), waste of dielectric sheets on which the pattern of the internal electrode layer is formed in (step 2), dielectric sheets on which the pattern of the internal electrode layer is not printed, excess laminate blocks such as scraps of laminate blocks discharged after the laminate blocks are cut in (step 4), defective laminate chips after cutting, waste after degreasing in (step 5), and waste after firing of laminate chips in (step 6).
  • a two-terminal multilayer ceramic capacitor having two terminals, the first external electrode 30a and the second external electrode 30b, has been described as a multilayer ceramic capacitor to be manufactured.
  • the scope of application of the present invention is not limited to the post-firing waste of a two-terminal multilayer ceramic capacitor.
  • the subject of application of the present invention is the post-firing waste of a multilayer ceramic capacitor having an internal electrode layer containing a first metal component such as Ni, an external electrode containing a second metal component such as Cu, and a ceramic layer containing a dielectric material such as BaTiO3 and a rare earth component that is an additive such as Dy. Therefore, the present invention may be applied to, for example, the post-firing waste of a three-terminal multilayer ceramic capacitor.
  • a three-terminal multilayer ceramic capacitor has a laminate 12 similar to those of the first and second embodiments described above, and first to fourth external electrodes.
  • the internal electrode layer 16 has a first internal electrode layer extended to the first end face 12e and the second end face 12f, and a second internal electrode layer extended to the first side face 12c and the second side face 12d.
  • a first external electrode is disposed on the first end face 12e of the laminate 12. The first external electrode is electrically connected to the first internal electrode layer exposed at the first end face 12e of the laminate 12.
  • a second external electrode is disposed on the second end face 12f of the laminate 12. The second external electrode is electrically connected to the first internal electrode layer exposed at the second end face 12f of the laminate 12.
  • a third external electrode is disposed on the first side face 12c of the laminate 12.
  • the third external electrode is electrically connected to the second internal electrode layer exposed at the first side surface 12c of the laminate 12.
  • a fourth external electrode is disposed on the second side surface 12d of the laminate 12.
  • the fourth external electrode is electrically connected to the second internal electrode layer exposed at the second side surface 12d of the laminate 12.
  • the first to fourth external electrodes may include only a baked electrode layer, or may include a baked electrode layer and a plating layer.
  • step (F) When the second separated material is dissolved in a mineral acid having no oxidizing power in step (D), the ceramic fine particles contained in the second separated material react with the mineral acid having no oxidizing power to become undissolved and precipitate.
  • the second metal fine particles such as Cu have a smaller ionization tendency than the hydrogen ions contained in the mineral acid having no oxidizing power, so they do not dissolve in the mineral acid having no oxidizing power.
  • the rare earth components in the rare earth-containing material dissolve to produce a rare earth component-containing solution.
  • the rare earth component-containing solution containing the undissolved materials can also be recovered as the rare earth components.
  • the solid-liquid separation step (F) such as filtration can be omitted.
  • step (G) Omission of neutralization in step (G)
  • the rare earth components in dissolving the second separated product in step (D), the rare earth components can be separated and recovered as a rare earth component-containing solution. Therefore, the neutralization in step (G) can be omitted.
  • step (C) Omission of various treatments in steps (I) and (J)
  • the first separated material containing the first metal fine particles in the magnetic separation in step (C), the first separated material containing the first metal fine particles can be separated and recovered as the first metal component. Therefore, steps (I) and (J) can be omitted.
  • the first metal solution in the dissolution of the first separated material in step (I), the first metal solution can be separated and recovered as the first metal component. Therefore, the filtration in step (J) can be omitted.
  • rare earth component compounds such as Dy(OH) 3 are separated and recovered as rare earth components in the neutralization step (G).
  • the method for separating and recovering rare earth components is not limited to this.
  • the rare earth components can be recovered as follows.
  • step (a) The rare earth component compound obtained by neutralization in step (G) is heat-treated to produce an oxide, and the oxide can be recovered as the rare earth component.
  • the rare earth component compound obtained after the neutralization in step (G) is Dy(OH) 3
  • dysprosium oxide (Dy 2 O 3 ) can be recovered as the rare earth component by heat treating Dy(OH) 3 .
  • the rare earth component compound obtained by neutralization in step (G) is dissolved in hydrochloric acid to produce a chloride, and the chloride can be recovered as the rare earth component.
  • the rare earth component compound obtained after the neutralization in step (G) is Dy(OH) 3
  • Dy(OH) 3 is dissolved in hydrochloric acid to produce a dysprosium chloride ( DyCl3 ) solution.
  • the dysprosium chloride solution is distilled to evaporate the solvent, and dysprosium chloride hexahydrate ( DyCl3.6H2O ) can be recovered as the rare earth component.
  • the rare earth component compound Dy(OH) 3 obtained after neutralization in step (G) is dissolved in hydrochloric acid to produce a dysprosium chloride solution, which is then further purified to recover a high-purity rare earth component.
  • the dysprosium chloride solution produced as described above can be purified by solvent extraction, and a high-purity dysprosium chloride solution can be recovered as a rare earth component.
  • Solvent extraction is a separation and purification method that utilizes the partitioning of solutes, in which a solute dissolved in one of the oil phase and the water phase, which are immiscible liquids, is transferred to the other phase.
  • an ion exchange resin method can be used as a method other than solvent extraction.
  • high-purity dysprosium oxide can be recovered from the high-purity dysprosium chloride solution obtained by the solvent extraction in (c) above.
  • oxalic acid is added to the high-purity dysprosium chloride solution to precipitate dysprosium oxalate.
  • high-purity dysprosium oxalate hexahydrate Dy2 ( C2O4 ) 3.6H2O ) is recovered .
  • high-purity dysprosium oxide ( Dy2O3 ) can be recovered as a rare earth component.
  • high-purity dysprosium chloride hexahydrate can be recovered from the high-purity dysprosium chloride solution obtained by the above-mentioned solvent extraction (c).
  • high-purity dysprosium chloride hexahydrate is recovered by distilling off the high-purity dysprosium chloride solution and evaporating the solvent.
  • the rare earth component-containing solution separated and recovered in the filtration of step (F) is input to the neutralization of step (G).
  • the rare earth component-containing solution separated and recovered in the filtration of step (F) may be treated in a rare earth component concentration step and then input to the neutralization of step (G).
  • the rare earth component concentration step is performed after the filtration of step (F) and before the neutralization of step (G).
  • the rare earth component concentration process is not limited as long as it is a method that can improve the recovery amount of rare earth components in the rare earth component-containing solution.
  • Examples of rare earth component concentration processes include, but are not limited to, (f1) ion exchange method, (f2) solvent extraction method, and (f3) distillation of the solvent from the solution. Below, (f1) to (f3) are each explained as a representative example.
  • the ion exchange method is a method in which dissolved ions dissolved in a solvent are adsorbed to an ion exchanger such as an ion exchange resin and a chelating resin.
  • an ion exchanger such as an ion exchange resin and a chelating resin.
  • a rare earth component-containing solution is passed through an ion exchanger, so that the rare earth components in the rare earth component-containing solution are adsorbed to the ion exchanger.
  • the ion exchange method is not limited, but is carried out, for example, by passing a rare earth component-containing solution through a column filled with an ion exchanger.
  • the column is formed of a cylindrical body with an open upper and lower ends, and the rare earth component-containing solution is introduced into the column from the upper end side of the column, and the rare earth component is adsorbed to the ion exchanger in the process of passing through the ion exchanger. The remaining liquid of the rare earth component-containing solution that has passed through the ion exchanger is discharged from the lower end side of the column.
  • the rare earth components adsorbed on the ion exchanger are eluted from the ion exchanger using an eluent.
  • the eluent is passed through the bottom end of a column packed with the ion exchanger to which the rare earth components are adsorbed.
  • the rare earth components are eluted from the ion exchanger into the eluent by the eluent.
  • the eluent from which the rare earth components have been eluted is collected from the top end of the column.
  • the rare earth components can be collected by filtering the eluent in which the rare earth components are dissolved, for example, using a filter.
  • the concentration of the rare earth components contained in the eluent can be made higher than the concentration of the rare earth components contained in the rare earth component-containing solution.
  • the rare earth component-containing solution is passed from the top to the bottom of the column, and then the eluent is passed from the bottom to the top of the column.
  • the rare earth components can be dissolved in the eluent after being adsorbed by the ion exchanger, there is no limitation on the direction in which the rare earth component-containing solution and eluent are passed through the column.
  • the series of steps (1) including steps (A) to (F) and the rare earth component concentration step by ion exchange may be carried out only once.
  • the series of steps (1) is carried out only once by passing the rare earth component-containing solution after steps (A) to (F) through an ion exchanger once.
  • a series of steps (1) including steps (A) to (F) and a rare earth component concentration step by ion exchange may be performed multiple times.
  • a series of steps (1) in which the rare earth component-containing solution after steps (A) to (F) is passed through an ion exchanger is performed multiple times.
  • the same ion exchanger can be used in each series of steps (1).
  • a series of steps (2) including steps (A) to (F) is performed multiple times, and the rare earth component-containing solution obtained in each series of steps (2) is temporarily stored.
  • the accumulated rare earth component-containing solution may then be treated all at once in a rare earth component concentration step using an ion exchange method.
  • the amount of rare earth component-containing solution accumulated after multiple series of steps (2) is greater than the amount of rare earth component-containing solution obtained by one series of steps (2). Therefore, by passing the accumulated rare earth component-containing solution through an ion exchanger, more rare earth components can be adsorbed onto the ion exchanger, thereby increasing the amount of rare earth components recovered.
  • the concentration of rare earth components in the rare earth component-containing solution after one pass of the series of steps (2) from step (A) to step (F) is low, even if the rare earth component-containing solution is filtered using a filter, the amount of rare earth components that accumulate on the filter is small. Therefore, the recovery amount of rare earth components may not be high. However, the recovery amount of rare earth components can be increased by performing the rare earth component concentration step as described above.
  • Ion exchange resins which are ion exchangers, include, but are not limited to, cation exchange resins and chelating resins.
  • Cation exchange resins include, but are not limited to, gel-type cation exchange resins, strong acid cation exchange resins, and weak acid cation exchange resins.
  • Specific examples of cation exchange resins include, but are not limited to, Amberlite IR-120B (manufactured by Organo Corporation), Duolite C20J (manufactured by Sumika Chemtex Corporation), DIAION SK-110 (manufactured by Mitsubishi Chemical Corporation), and Purolite C100 (manufactured by Purolite Corporation).
  • the chelating resin which is an ion exchanger, is not limited to, but may be, for example, a resin having a chelating group or chelating ability, such as a thiourea group, a thiouronium group, a phosphonic acid, an amino phosphoric acid, an amino carboxylic acid, an alkylamino group, a pyridine ring, a cyclic cyanine, or a cyclic ether.
  • Specific examples of the chelating resin include, but are not limited to, Sumichelate MC700 (manufactured by Sumika Chemtex Corporation) and Purolite MTS9300 (manufactured by Purolite Corporation).
  • the solvent extraction method includes, for example, a solvent extraction step and a stripping step.
  • the solvent extraction process is a process in which a water-insoluble organic phase containing a metal extractant is contacted and mixed with a rare earth-containing solution in order to separate rare earth components from the rare earth-containing solution.
  • a phase separation step is carried out to separate the rare earth-containing water-insoluble organic phase from the aqueous phase.
  • the phases are separated by utilizing the specific gravity difference between the rare earth-containing water-insoluble organic phase and the aqueous phase that have been subjected to the solvent extraction step.
  • the rare earth-containing water-insoluble organic phase obtained through the phase separation process is contacted and mixed with an acidic aqueous solution, thereby back-extracting the rare earth components in the water-insoluble organic phase into the acidic aqueous solution.
  • steps (1) including steps (A) to (F) and the rare earth component concentration step using a solvent extraction method may be carried out only once.
  • a series of steps (1) including steps (A) to (F) and a rare earth component concentration step by a solvent extraction method may be performed multiple times.
  • a series of steps (1) in which the rare earth component-containing solution after steps (A) to (F) is mixed with an organic solvent is performed multiple times. For example, by repeatedly mixing the rare earth component-containing solution recovered from steps (A) to (F) multiple times with the same organic solvent, more rare earth components are transferred to the organic solvent than when the rare earth component-containing solution recovered from steps (A) to (F) is mixed with the organic solvent once. This makes it possible to increase the amount of rare earth components recovered.
  • the rare earth component-containing solution obtained in each series of steps (2) is temporarily stored. After that, the stored rare earth component-containing solution may be treated all at once in a rare earth component concentration step using a solvent extraction method.
  • Removal of solvent from solution involves removing the solvent from a solution in which dissolved ions are dissolved.
  • the removal of the solvent can be carried out, for example, using an evaporator, but is not limited thereto.
  • the evaporator is a device that evaporates the solvent by, for example, heating and reducing the pressure inside an evaporator in which a solution is placed. Examples of the evaporator include a rotary evaporator and a flash evaporator.
  • the operating conditions of the evaporator are appropriately adjusted depending on the amount of unburned waste to be processed before or after the production and degreasing, various additive components to the unburned waste, and the like.
  • steps (1) including steps (A) to (F) and the step of concentrating the rare earth components by distilling off the solvent from the solution may be carried out once or multiple times.
  • the rare earth component-containing solution obtained in each series of steps (2) is temporarily stored. After that, the accumulated rare earth component-containing solution may be treated all at once to distill off the solvent.
  • the state of the recovered rare earth component may be any of a liquid state, a solid state, and a mixed state of liquid and solid.
  • the crystal lattice of the rare earth component may be any of an amorphous state, a crystalline state, and a mixed state of amorphous and crystalline.
  • the first metal fine particles are dissolved in a mineral acid in the dissolution of the first separated product in step (I).
  • the first metal solution is then separated and recovered as the first metal component.
  • the first metal solution containing the precipitated ceramic fine particles is filtered, and the first metal solution from which the ceramic fine particles have been removed is separated and recovered as the first metal component.
  • the separation and recovery of the first metal component is not limited to this.
  • the first metal component can be recovered as follows.
  • the first metal component compound can be recovered as the first metal component by crystallizing the first metal solution.
  • the first metal solution obtained after dissolving the first metal fine particles in step (I) is a nickel sulfate ( NiSO4 ) solution
  • nickel sulfate hexahydrate ( NiSO4.6H2O ) can be recovered as the first metal component by crystallizing and filtering the nickel sulfate solution.
  • a high-purity first metal component By purifying the first metal solution obtained after dissolving the finely divided first metal product in step (I), a high-purity first metal component can be recovered.
  • a nickel sulfate (NiSO 4 ) solution which is the first metal solution, can be purified by an ion exchange resin method, a solvent extraction method, or the like, and a high-purity nickel sulfate solution can be recovered as the first metal component.
  • the first metal solution obtained after dissolving the first metal fine particles in step (I) can be purified by a method other than the above-mentioned (b) to recover a high-purity first metal component.
  • a nickel sulfate solution which is a first metal solution
  • solid high-purity Ni can be precipitated by a method of precipitating a solid dissolved in the solution, such as electrolytic deposition, and recovered as the first metal component.
  • nickel chloride hexahydrate NiCl2.6H2O
  • nickel chloride hexahydrate NiCl2.6H2O
  • a high-purity nickel chloride ( NiCl2 ) solution is produced by dissolving the high-purity Ni recovered in the above (d) in hydrochloric acid.
  • NiCl2 nickel chloride
  • spray-drying the nickel chloride solution high-purity nickel chloride hexahydrate is produced.
  • By further drying the high-purity nickel chloride hexahydrate with hot air even higher purity nickel chloride hexahydrate can be recovered as the first metal component.
  • the first metal solution obtained after dissolving the finely divided first metal product in step (I) is neutralized to generate a chloride, and the chloride can be recovered as the first metal component.
  • a nickel sulfate solution which is a first metal solution
  • the precipitated nickel hydroxide (Ni(OH) 2 ) is separated and recovered, for example, by filtration.
  • nickel hydroxide is dissolved in hydrochloric acid to produce a nickel chloride ( NiCl2 ) solution.
  • nickel chloride hexahydrate NiCl2.6H2O
  • the state of the recovered metal component may be any of a liquid state, a solid state, and a mixed state of liquid and solid.
  • the crystal lattice of the metal component may be any of an amorphous state, a crystalline state, and a mixed state of amorphous and crystalline.
  • the manufacturing method of the multilayer ceramic capacitor 10 includes the formation of a laminated block (step 3), cutting into laminated chips (step 4), degreasing (step 5), firing of the laminated chips (step 6), and application and firing of the baked electrode layer paste (step 7) in that order.
  • the manufacturing method of the multilayer ceramic capacitor 10 is not limited to this, and for example, before the degreasing in step 5 and before the firing (firing of the laminated chips) in step 6, the baked electrode layer paste may be applied to the unfired laminated chips, and then the degreasing and firing of the baked electrode layers may be performed.
  • the baked electrode layer paste containing Ni, glass components, resin components, etc. is applied to the laminated chips before the degreasing in step 5.
  • the laminated chips to which the baked electrode layer paste has been applied are degreased, and then the baked electrode layers are fired.
  • the temperature during degreasing is preferably, for example, higher than 800° C. and lower than 1000° C.
  • the firing temperature for the fired electrode layer is preferably, for example, higher than 1000° C. and not higher than 1400° C.
  • step (C) the finely divided post-sintering waste material in the step (B) is mixed with an aqueous solvent to generate a slurry, and then the first separated matter and the second separated matter are respectively recovered using the magnet.
  • ⁇ 4> The method for separating and recovering rare earth components and metal components from waste after firing of a multilayer ceramic capacitor according to any one of ⁇ 1> to ⁇ 3>, wherein in the step (D), the rare earth component-containing solution is adjusted to a pH of 1.5 or more and 2.5 or less by adding the mineral acid having no oxidizing power.
  • ⁇ 5> The method for separating and recovering rare earth components and metal components from post-sintering waste of multilayer ceramic capacitors according to any one of ⁇ 1> to ⁇ 4>, wherein in the step (E), the second metal solution is adjusted to a pH of 9 or more and a pH of 10 or less by adding the ammonia water.
  • ⁇ 6> A method for separating and recovering rare earth components and metal components from unburned waste before production and degreasing according to any one of ⁇ 1> to ⁇ 5>, further comprising a step of performing solid-liquid separation of the rare earth component-containing solution containing the precipitated ceramic fine particles and the undissolved second metal fine particles.
  • ⁇ 7> The method for separating and recovering rare earth components and metal components from unburned waste before production and degreasing according to ⁇ 6>, further comprising a rare earth component concentration step of concentrating the rare earth components in the rare earth component-containing solution after the step (F).
  • ⁇ 8> The method for separating and recovering rare earth components and metal components from post-sintering waste of multilayer ceramic capacitors according to any one of ⁇ 1> to ⁇ 7>, wherein the first metal component is Ni.
  • ⁇ 10> The method for separating and recovering rare earth components and metal components from post-sintering waste of multilayer ceramic capacitors according to any one of ⁇ 1> to ⁇ 9>, wherein the ceramic particles are BaTiO 3 .
  • ⁇ 11> The method for separating and recovering rare earth components and metal components from post-sintering waste of multilayer ceramic capacitors according to any one of ⁇ 1> to ⁇ 10>, wherein the rare earth components are at least one of Dy, Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Ho, Er, Tm, Yb, and Lu.
  • ⁇ 12> (A) preparing sintered waste of a multilayer ceramic capacitor, the multilayer ceramic capacitor comprising: a laminate including a ceramic layer and an internal electrode layer; a fired electrode layer disposed on the laminate and connected to the internal electrode layer; and a first-stage plating layer disposed on the fired electrode layer as an outermost layer, the ceramic layer having an aggregate of a plurality of ceramic particles, a rare earth-containing material containing a rare earth component is contained in grain boundaries between the plurality of ceramic particles, the internal electrode layer contains a first metal component which is a magnetic base metal, the fired electrode layer contains a second metal component which is a non-magnetic precious metal, the first-stage plating layer contains the first metal component, and the ceramic layer, the internal electrode layer, and the fired electrode layer are sintered; (B) obtaining a ceramic micro-fine product in which the ceramic layer is micro-fine, the rare earth-containing material, the internal electrode layer and the first-stage plating layer are micro-fine, and a second metal micro-fine product in which the
  • Multilayer ceramic capacitor 12 Laminate 12a: First main surface 12b: Second main surface 12c: First side surface 12d: Second side surface 12e: First end surface 12f: Second end surface 14: Ceramic layer 14_U: Unfired ceramic layer 16: Internal electrode layer 16_U: Unfired internal electrode layer 16a: First internal electrode layer 16b: Second internal electrode layer 30: External electrode 30a: First external electrode 30b: Second external electrode 32: Baked electrode layer 32a: First baked electrode layer 32b: Second baked electrode layer 34: Plating layer 34a: First plating layer 34b : Second plating layer 34a1 : First lower plating layer 34a2: First upper plating layer 34b1 : second lower plating layer 34b2 : second upper plating layer x: height direction y: width direction z: length direction

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Abstract

La présente invention concerne un procédé de séparation et de récupération d'un composé de terres rares et d'un composé métallique à partir de déchets après calcination. Ce procédé de séparation et de récupération comprend : (A) une étape de préparation d'un déchet après calcination d'un condensateur céramique multicouche dans lequel une couche céramique, une couche d'électrode interne qui contient un premier composé métallique magnétique, et une couche d'électrode cuite qui contient un second composé métallique non magnétique sont frittées ; (B) une étape de pulvérisation des déchets après calcination ; (C) une étape de séparation et de récupération, à l'aide d'un aimant, d'un premier matériau séparé qui contient une céramique pulvérisée et un premier métal pulvérisé, et d'un second matériau séparé qui contient une céramique pulvérisée, un matériau contenant des terres rares et un second métal pulvérisé ; (D) une étape de dissolution du second matériau séparé dans un acide minéral qui n'a pas de pouvoir d'oxydation, et la précipitation de la céramique pulvérisée et du second métal pulvérisé, générant ainsi une solution contenant un composé de terres rares dans laquelle le composé de terres rares dans le matériau contenant des terres rares est dissous; et (E) une étape de dissolution du précipité dans le second matériau séparé dans de l'ammoniaque, générant ainsi une seconde solution métallique dans laquelle le second composé métallique dans le second métal pulvérisé est dissous.
PCT/JP2024/026745 2023-11-29 2024-07-26 Procédé de séparation et de récupération d'un composé de terres rares et d'un composé métallique à partir de déchets de condensateurs céramiques multicouches après calcination Pending WO2025115287A1 (fr)

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PCT/JP2024/026745 Pending WO2025115287A1 (fr) 2023-11-29 2024-07-26 Procédé de séparation et de récupération d'un composé de terres rares et d'un composé métallique à partir de déchets de condensateurs céramiques multicouches après calcination

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US5129945A (en) * 1990-10-24 1992-07-14 The United States Of America As Represented By The Secretary Of The Interior Scrap treatment method for rare earth transition metal alloys
JP2007231382A (ja) * 2006-03-01 2007-09-13 Mitsui Mining & Smelting Co Ltd 希土類元素の回収方法
WO2017037625A1 (fr) * 2015-09-02 2017-03-09 Attero Recycling Pvt. Ltd. Procédé et processus de récupération de métaux précieux contenus dans des condensateurs céramiques monolithiques usagés
JP2018530673A (ja) * 2015-09-18 2018-10-18 ザ トラスティーズ オブ コロンビア ユニバーシティ イン ザ シティ オブ ニューヨークＴｈｅ Ｔｒｕｓｔｅｅｓ Ｏｆ Ｃｏｌｕｍｂｉａ Ｕｎｉｖｅｒｓｉｔｙ Ｉｎ Ｔｈｅ Ｃｉｔｙ Ｏｆ Ｎｅｗ Ｙｏｒｋ 鉄鋼スラグから製品を再生する方法およびシステム
WO2023156345A1 (fr) * 2022-02-18 2023-08-24 Commissariat A L'energie Atomique Et Aux Energies Alternatives Procédé de recyclage de néodyme à partir de cartes de circuits imprimés usagées

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CN111039495B (zh) * 2020-01-06 2024-05-17 湖南景翌湘台环保高新技术开发有限公司 一种废稀土抛光粉和钢铁酸洗废液的综合回收方法
CN115772599A (zh) * 2022-11-30 2023-03-10 江西闪凝科技有限公司 一种钕铁硼焙砂中有价金属元素的分离方法

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5129945A (en) * 1990-10-24 1992-07-14 The United States Of America As Represented By The Secretary Of The Interior Scrap treatment method for rare earth transition metal alloys
JP2007231382A (ja) * 2006-03-01 2007-09-13 Mitsui Mining & Smelting Co Ltd 希土類元素の回収方法
WO2017037625A1 (fr) * 2015-09-02 2017-03-09 Attero Recycling Pvt. Ltd. Procédé et processus de récupération de métaux précieux contenus dans des condensateurs céramiques monolithiques usagés
JP2018530673A (ja) * 2015-09-18 2018-10-18 ザ トラスティーズ オブ コロンビア ユニバーシティ イン ザ シティ オブ ニューヨークＴｈｅ Ｔｒｕｓｔｅｅｓ Ｏｆ Ｃｏｌｕｍｂｉａ Ｕｎｉｖｅｒｓｉｔｙ Ｉｎ Ｔｈｅ Ｃｉｔｙ Ｏｆ Ｎｅｗ Ｙｏｒｋ 鉄鋼スラグから製品を再生する方法およびシステム
WO2023156345A1 (fr) * 2022-02-18 2023-08-24 Commissariat A L'energie Atomique Et Aux Energies Alternatives Procédé de recyclage de néodyme à partir de cartes de circuits imprimés usagées

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