WO2015059777A1

WO2015059777A1 - Method for separating actinide and device for treating spent fuel

Info

Publication number: WO2015059777A1
Application number: PCT/JP2013/078638
Authority: WO
Inventors: 大輔渡邉; 祐子可児; 笹平　朗
Original assignee: 株式会社日立製作所
Priority date: 2013-10-23
Filing date: 2013-10-23
Publication date: 2015-04-30

Abstract

Provided is a method for separating actinides from a spent fuel using an ionic liquid and using a device having a simple equipment configuration. The method comprises reacting a spent fuel with fluorine gas to convert the chemical forms of the actinides into fluorides which are soluble in an ionic liquid, dissolving the actinide-containing fluoride residues in the ionic liquid, and then separating and recovering the dissolved actinides. The problem of the invention can be solved therewith.

Description

Actinide separation method and spent fuel processor

The present invention relates to a method and apparatus for separating spent fuel components into uranium and plutonium, minor actinides and fission products, that is, a separation method and spent fuel processing apparatus for separating actinides.

The spent fuel discharged from the nuclear power plant is planned to be processed into vitrified material and disposed of after the nuclear fuel material is recovered by reprocessing. When reprocessing by the current PUREX method, the vitrified material contains minor actinides, which are radionuclides with a very long half-life, and therefore the vitrified material can reach hundreds of thousands of years by geological disposal. It is said that it needs to be kept stable. Here, the actinide means an element having an atomic number of 89 to 103, and corresponds to an element group called uranium (U), plutonium (Pu), or a minor actinide used as nuclear fuel. The minor actinide refers to an element obtained by removing Pu from a transuranium element among actinide elements, and corresponds to neptunium, americium, curium, and the like.

Currently, for the purpose of shortening the confinement period of vitrified solids, the minor actinides are separated from the high-level radioactive liquid waste generated during the reprocessing of spent fuel, and the neutrons are irradiated to the minor actinides to give a short half-life radionuclide. The technology of converting to is being studied. Here, the high level radioactive liquid waste is a liquid after separation of uranium (U) and Pu from a solution in which spent fuel is dissolved in nitric acid. The high level radioactive liquid waste mainly contains fission products and minor actinides. Is dissolved. In summary, uranium and plutonium are separated by reprocessing spent fuel, and minor actinides are separated by a minor actinide separation process from high-level radioactive liquid waste. Each product is separated. Various methods for separating minor actinides from high-level radioactive liquid waste have been studied. For example, methods for selectively separating minor actinides from high-level radioactive liquid waste using an extractant have been studied.

On the other hand, in recent years, a substance called an ionic liquid, which is a substance consisting only of ions and has a property of becoming a liquid near room temperature, has attracted attention. The ionic liquid can change the combination of the cation and anion which comprise it according to various uses. Typical cations include imidazolium, pyridinium, pyrrolidinium, piperidinium, ammonium, and phosphonium. Representative anions include halide ions (Cl ⁻ , Br ⁻ , I ⁻ ), tetrafluoroborate (BF ₄ ⁻ ), hexafluorophosphate (PF ₆ ⁻ ), bis (trifluoromethylsulfonyl) amide ( C ₂ F ₆ NO ₄ S ₂ ⁻ ), trifluoromethanesulfonate (CF ₃ O ₃ S ⁻ ), trifluoroacetate (CF ₃ COO ⁻ ) and the like.

Currently, research is being conducted to separate elements contained in spent fuel using this ionic liquid. For example, Japanese Patent Publication No. 2002-503820 discloses a method of separating U and Pu by dissolving a spent fuel or a substance containing a spent fuel component in an ionic liquid.

Also, Japanese Patent Publication No. 2001-516871 describes a method of regenerating used metal salt generated when reprocessing irradiated fuel with molten salt with an ionic liquid.

[Non-Patent Document 1] describes a method of separating various elements by supplying components contained in spent fuel such as uranium oxide to an ionic liquid, blowing chlorine gas into the ionic liquid, and performing electrolysis. .

As described above, when reprocessing spent fuel or handling radionuclide-containing substances, the ionic liquid contains hydrogen atoms that tend to decelerate neutrons compared to water-based solvents such as nitric acid solutions. Since the amount of ionic liquid used as a solvent is smaller than the method using water as a solvent, it is less likely to generate decelerated neutrons that contribute to the criticality, that is, it is easier to manage operations without causing criticality. There are benefits.

Japanese translation of PCT publication No. 2002-503820 Japanese Patent Laid-Open No. 2004-233066 JP 2012-47546 A JP 2013-101066 A JP 2002-257980 A JP 2010-127616 A JP 2001-516871 A

Japanese Patent Publication No. 2002-503820 discloses a method for dissolving a spent fuel or a substance containing its component in an ionic liquid, but data such as the amount of the spent fuel component dissolved in the ionic liquid is shown. Absent. In [Non-Patent Document 1], it is necessary to blow chlorine gas, which is corrosive gas, into the ionic liquid in order to dissolve and separate spent fuel components. In this method, chlorine gas is treated. It is expected that the equipment will be complicated, such as the need to install off-gas treatment equipment. Moreover, since chlorine gas is used in [Non-Patent Document 1], it is expected that a normal spent fuel whose chemical form is an oxide is hardly dissolved in an ionic liquid as it is. Easily dissolving the spent fuel component in the ionic liquid is also considered as a particular problem of the method of separating the spent fuel component using the ionic liquid.

Therefore, there is a need for a technique capable of easily dissolving spent fuel components in an ionic liquid in a simple facility that does not require blowing gas into the ionic liquid.

In the present invention, spent fuel is reacted with a fluorinating agent to produce solid fluoride, the produced solid fluoride is dissolved in an ionic liquid, and U and Pu, fission from the solution in which the solid fluoride is dissolved in the ionic liquid The above problems are solved by separating the product and minor actinide.

The present invention also provides a fluorination treatment apparatus for producing a solid fluoride by reacting a spent fuel with a fluorinating agent, a dissolution tank for producing a solution in which the solid fluoride is dissolved in an ionic liquid, and the solution. The above-described problems are solved by providing a separation device that separates U and Pu, fission products, and minor actinides.

According to the present invention, components of spent fuel can be efficiently dissolved in an ionic liquid, and facilities for separating spent fuel components into U and Pu, fission products, and minor actinides are provided. It can be a simple facility. In the present invention, separating U and Pu, fission products, and minor actinides will be referred to as separating actinides.

It is a flowchart which shows the isolation | separation process of the actinide from the spent fuel which is one Example of this invention. It is the schematic of the spent fuel processing apparatus which is 1st Example of this invention. It is the schematic of the spent fuel processing apparatus which is 2nd Example of this invention.

The present inventors have newly found through experiments that a compound having a chemical form of fluoride has high solubility in an ionic liquid. Table 1 shows the amount of fluoride dissolved in the ionic liquid obtained by this experiment.

In the experiment by the present inventors, among the ionic liquids composed of combinations of anions and cations shown in Table 1, an ionic liquid of a combination of anions and cations whose dissolution amount is described is used, and an ionic liquid of cerium fluoride is used. The solubility in was determined. Specifically, imidazolium-based, pyridinium-based, and pyrrolidinium-based ionic liquids were used as cations. The horizontal axis in Table 1 lists the cationic species in the order of Lewis acidity of cations, and further describes ammonium cations for reference. In addition, the vertical axis in Table 1 represents tetrafluoroborate (BF ₄ ⁻ ), hexafluorophosphate (PF ₆ ⁻ ), bis (trifluoromethylsulfonyl) amide (C ₂ F ₆ NO ₄ S ₂ ⁻ ) as anions. , Trifluoromethanesulfonate (CF ₃ O ₃ S ⁻ ), chloride ion (Cl ⁻ ) were used in the experiment. Similar to the cation, in Table 1, anion species are arranged in the Lewis basic order of anions, and trifluoroacetate (CF ₃ COO ⁻ ) is described as a reference. As an experimental method, cerium fluoride was typically supplied to each ionic liquid, dissolved at a temperature of 100 ° C. with stirring for 1 hour, and then the amount of cerium dissolved in the solution was measured. . It is said that ionic liquids have been developed since the 1990s, and there are almost no examples in which the amount of inorganic compounds dissolved in such ionic liquids has been reported.

According to Table 1, an ionic liquid having an imidazolium cation has a strong Lewis basic ionic liquid and tends to have a high dissolution amount, and an anion of BF ₄ ⁻ or C ₂ F ₆ NO ₄ S ₂ ⁻ . An ionic liquid having a low Lewis acidity tends to increase the amount of dissolution. Therefore, it is considered that fluoride is best dissolved in an ionic liquid composed of a cation with weak Lewis acidity and an anion with strong Lewis basicity. According to Table 1, the weakest BF ₄ cation and the Lewis basicity of the Lewis acid strongest imidazolium ^- even ionic liquids composed of a combination of anion, since it is possible to dissolve the fluoride, at least Table 1 It is considered that the fluoride can be dissolved if the ionic liquid is a combination of an anion and a cation shown in FIG.

The present inventors have devised a process for separating actinides using the newly acquired knowledge that fluoride dissolves in ionic liquids. In the actinide separation process of the present invention, the spent fuel is reacted with fluorine gas, the spent fuel is converted into a form of fluoride that is easily dissolved in the ionic liquid, and the fluoride residue containing the actinide is dissolved in the ionic liquid, The dissolved elements are separated by operations such as solvent extraction.

The apparatus for reacting the spent fuel with fluorine gas is referred to in the flame furnace system referred to in Japanese Patent Application Laid-Open Nos. 2004-233066 and 2012-47546, and in Japanese Patent Application Laid-Open No. 2013-101666. A batch type fluorination apparatus can be used. By using such a fluorination apparatus, it is possible to react spent fuel with fluorine gas and convert it into fluoride.
Example 1
A first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a flowchart of the present embodiment showing the steps until the actinide is separated from the spent fuel. In this embodiment, a fluorination step 1 for fluorinating the spent fuel 4, a dissolution step 2 for dissolving the fluoride residue (solid fluoride) 7 obtained in the fluorination step 1 with an ionic liquid 8, and dissolution A separation step 3 for separating U and Pu10, fission product 11, and minor actinide 12 from the solution 9 obtained in step 2 is provided. Below, the processing method of the spent fuel of a present Example is demonstrated in detail.

Since the spent fuel 4 discharged from the nuclear power plant is stored in a cladding tube, it is sheared and decoated by an existing method implemented in a reprocessing plant. The spent fuel 4 thus obtained is reacted with the fluorine gas 5 in the fluorination step 1. In the fluorination step 1, a flame furnace type or batch type fluorination apparatus can be used. The fluorine gas 5 is very reactive, and almost all the components of the spent fuel 4 react with the fluorine gas 5 and the chemical form is converted from oxide to fluoride. Since the spent fuel 4 contains various elements and the boiling points of the fluorides differ greatly, in the fluorination step 1, mainly volatile uranium hexafluoride (UF ₆ gas 6) and fluoride are used. It is divided roughly into residue 7. The fluoride residue 7 contains Pu, fission products, minor actinides, and small amounts of U.

The fluoride residue 7 is collected, and the fluoride residue 7 is dissolved in the ionic liquid 8 in the dissolution step 2 to obtain a solution 9. As the ionic liquid 8, any of ionic liquids in which cations and anions shown in Table 1 are combined can be used. Table 1 shows the amount of cerium fluoride dissolved in each ionic liquid as a representative example, but the actinide element, which is an element for separation in this example, is an element of the same group as cerium. The actinide fluoride is considered to dissolve in the ionic liquid as well.

Finally, in the separation step 3, the elements dissolved in the solution 9 are separated by various separation methods using differences in chemical properties of the elements and the size of the compounds, and U and Pu10, fission products 11, Each minor actinide 12 can be obtained. As the separation method, an extraction separation method in which an element is selectively recovered using an extractant, an electrolysis method, an adsorption method in which an element is selectively adsorbed on an adsorbent, and the like are effective.

After separation for each element group in this way, U and Pu10 are reused as nuclear fuel through treatment such as oxide conversion. The fission product 11 is vitrified. Minor actinides 12 are transmutated by neutron irradiation or the like, converted into nuclides with a short half-life, and then solidified in the same manner as fission products.

In this embodiment, U and Pu10 and minor actinide 12 are separated. However, according to the usage of these elements, Pu and minor actinide 12 may be collected together without being separated. .

In this embodiment, the fluorine gas 5 is used as a fluorinating agent for converting the spent fuel 4 into fluoride. However, boron fluoride, carbon fluoride, nitrogen fluoride, chlorine fluoride, bromine fluoride, fluorine The same effect can be obtained by using a fluorinating agent such as iodine fluoride.

According to the present embodiment, the spent fuel component can be dissolved by a simple method that does not require an operation such as blowing a gas into the ionic liquid by converting the spent fuel component into a chemical form of fluoride. Thus, it is possible to obtain an effect that the minor actinide can be separated from other elements by various separation operations by being dissolved.

The spent fuel processing apparatus of the present embodiment that separates minor actinides from spent fuel will be described with reference to FIG. The spent fuel processing apparatus of the present embodiment includes a flame furnace 20, a residue receiving tank / dissolution tank 21, a valve A22, a valve B23, a valve C24, a valve D25, a valve E27, a pump 26, and a separation device 28. A valve A22 and a valve B23 are installed between the flame furnace 20 and the residue receiving and melting tank 21. By opening the valve A22 and the valve B23, the flame furnace 20 and the residue receiving tank / dissolving tank 21 are connected, and by closing the valve A22 and the valve B23, the pipe between the frame furnace 20 and the residue receiving tank / dissolving tank 21 is closed. A valve C24 is installed between a collection container (not shown) for collecting the UF ₆ gas 6 and the residue receiving tank / dissolution tank 21. By opening the valve C24, the gas UF ₆ gas 6 is transferred to the outside of the residue receiving tank / dissolving tank 21 and collected in a recovery container. By closing the valve C24, the UF ₆ gas is transferred to the residue receiving tank / dissolving tank 21. From being transferred to the collection container. A valve D25 is installed between a tank (not shown) in which the ionic liquid 8 is stored and the residue receiving tank / dissolving tank 21. By opening the valve D25, the ionic liquid 8 is injected into the residue receiving tank / dissolving tank 21. Further, by closing the valve D25, the injection of the ionic liquid 8 into the residue receiving tank / dissolving tank 21 is stopped. A valve E27 is installed between the pump 26 and the residue receiving / dissolving tank 21. By opening the valve E27 while the pump 26 is driven, the solution 9 in which the fluoride residue 7 is dissolved in the ionic liquid 8 can be taken out of the residue receiving tank / dissolving tank 21. By closing the valve E27, the removal of the solution 9 from the residue receiving tank / dissolving tank 21 is stopped. A separation device 28 is connected to the subsequent stage of the pump 26.

Next, a procedure for separating actinides from spent fuel using the spent fuel processing apparatus of this embodiment will be described. First, in order to fluorinate the spent fuel 4, the valves A22, B23, and C24 are opened, and the valves D25 and E27 are closed. Next, the spent fuel 4 that has been sheared and decoated is reacted with the fluorine gas 5 in a flame furnace 20. In the flame furnace method, spent fuel 4 and fluorine gas 5 are reacted at a high speed in a high temperature region called a frame 13. The temperature in the frame 13 is maintained by the reaction heat of fluorination. In the flame furnace system, continuous treatment is possible, and the spent fuel 4 and the fluorine gas 5 in an amount more than that necessary for fluorination thereof can be continuously supplied. As shown in FIG. 1, UF ₆ gas 6 and fluoride residue 7 are generated by fluorination treatment of the spent fuel 4. Since the fluoride residue 7 is solid, it falls from the lower part of the frame furnace 20 and is collected in the residue receiving tank / dissolving tank 21. Since the UF ₆ gas 6 is a gas, it passes through the frame furnace 20 and the residue receiving tank / dissolving tank 21 and is transferred to the outside of the residue receiving tank / dissolving tank 21 through the valve C24. The UF ₆ gas 6 is collected separately, purified and concentrated, and then reused as nuclear fuel.

Next, when the fluorination treatment of the predetermined amount of the spent fuel 4 is completed, the supply of the spent fuel 4 and the fluorine gas 5 to the flame furnace 20 is stopped. Next, valve A22, valve B23, valve C24 and valve E27 are closed, and valve D25 is opened. The ionic liquid 8 is supplied to the residue receiving tank / dissolution tank 21 from a pipe connected to the valve D25. The fluoride residue 7 is dissolved in the ionic liquid 8 in the residue receiving and dissolving tank 21. The solution at this time is referred to as Solution 9.

A stirring device for stirring the solution 9 may be installed in the residue receiving and dissolving tank 21. By providing the stirring device, it is possible to shorten the time for the components contained in the fluoride residue 7 to dissolve in the ionic liquid 8.

A heat exchanger (heating device) for adjusting the temperature of the ionic liquid 8 or the solution 9 may be installed in the residue receiving tank / dissolution tank 21. By heating the temperature of the solution 9 in which the ionic liquid 8 or the fluoride residue 7 is dissolved by the heat exchanger, the time during which the fluoride residue 7 is dissolved in the solution 9 can be shortened.

When the operation of dissolving the fluoride residue 7 in the ionic liquid 8 is completed, the operation of transferring the solution 9 in the residue receiving and dissolving tank 21 to the separation device 28 is performed. By opening the valve E27 and operating the pump 26 to drive the pump, the solution 9 in the residue receiving tank / dissolving tank 21 is transferred to the separation device 28. Separation device 28 separates minor actinide 12, uranium and plutonium 10 and fission product 11 from solution 9.

It becomes possible to easily separate the actinide from the spent fuel 4 by using the spent fuel processing apparatus of this embodiment.

According to the spent fuel processing apparatus of the present embodiment, the receiving tank for the fluoride residue 7 and the dissolving tank are the same equipment, so that there is no need to recover the fluoride residue 7 from the receiving tank and transfer it to another dissolving tank. The benefits can be obtained.

The spent fuel processing apparatus of the present embodiment is a very simple facility because it is not necessary to blow chlorine gas or the like in the dissolving step 2 for dissolving the fluoride residue 7 obtained from the spent fuel into the ionic liquid. be able to.

An example of recovering nuclear fuel material by the PUREX method after reacting spent fuel with fluorine gas as in JP-A-2002-257980 can be considered. An example in which this method is combined with a method of selectively separating minor actinides from high-level radioactive liquid waste using an extractant is also considered as Comparative Example 1. When the method for separating the minor actinides according to the comparative example 1 and the present example is compared, the dissolution process 2 of the present example does not use water, so that the effect that the critical control is easy can be obtained.

As a comparative example 2, a method in which spent fuel is reacted with fluorine gas and solid fluoride is dissolved in a molten salt and elements are separated by electrolysis as disclosed in Japanese Patent Application Laid-Open No. 2010-127616. When comparing the comparative example 2 and the method for separating the minor actinides according to the present embodiment, in the comparative example 2, the temperature of the dissolution step generally needs to be several hundred degrees Celsius. Since it can melt | dissolve near, according to a present Example, the effect that the temperature of a melt | dissolution process can be made low can be acquired.
(Example 2)
A second embodiment of the present invention will be described with reference to FIG. In the spent fuel processing apparatus of Example 1, a flame furnace 20 and a residue receiving tank / dissolving tank 21 are connected via a valve A22 and a valve B23, a recovery container for recovering the UF ₆ gas 6, the recovery container and the residue receiving tank was configured to include a valve C24 which is installed between and dissolving tank 21, but spent fuel processing apparatus of the present embodiment is a configuration without a collecting container for collecting the frame oven and UF ₆ gas 6. The spent fuel processing apparatus of the present embodiment will be described below with a focus on the configuration different from that of the first embodiment.

The spent fuel processing apparatus of this embodiment includes a dissolution tank 30, a heat exchanger 33, a pump 26, a valve E27, a valve F31, and a valve G32. A valve F31 is installed between the fluoride residue container (not shown) in which the fluoride residue 7 is stored and the dissolution tank 30. The fluoride residue container and the dissolution tank 30 are connected by opening the valve F31, and the piping between the fluoride residue container and the dissolution tank 30 is closed by closing the valve F31. A heat exchanger 33 is installed in the dissolution tank 30.

Next, the procedure for separating the minor actinide from the spent fuel using the spent fuel processing apparatus of this embodiment will be described. The spent fuel is fluorinated in a separately installed flame furnace. In this embodiment, an example in which the fluorination step 1 is performed using a flame furnace will be described, but the fluorination step may be performed using a batch type fluorination apparatus. The generated fluoride residue 7 is collected in advance and stored in a fluoride residue container. In order to dissolve the fluoride residue 7, the valve E27 is closed, the valve G32 is opened, and the ionic liquid 8 is supplied to the dissolution tank 30 from a pipe connected to the valve G32. Next, the valve F31 is opened, and the fluoride residue 7 is supplied to the dissolution tank 30 from the pipe connected to the valve F31. The fluoride residue 7 is dissolved in the ionic liquid 8 in the dissolution tank 30. The solution at this time is referred to as Solution 9.

A stirring device for stirring the solution 9 may be installed in the dissolution tank 30. By providing the stirring device, it is possible to shorten the time for the components contained in the fluoride residue 7 to dissolve in the ionic liquid 8.

A heating device that adjusts the temperature of the ionic liquid 8 or the solution 9 may be installed in the dissolution tank 30. Since the spent fuel processing apparatus of the present embodiment includes the heat exchanger 33 in the dissolution tank 30, the solution 9 can be heated using the heat exchanger 33. Since the heat exchanger 33 heats the solution 9 in which the ionic liquid 8 or the fluoride residue 7 is dissolved, the time for which the fluoride residue 7 is dissolved in the solution 9 can be shortened.

When the operation of dissolving the fluoride residue 7 in the ionic liquid 8 is completed, the operation of transferring the solution 9 to the separation device 28 is performed. By opening the valve E27 and operating the pump 26 to drive the pump, the solution 9 in the dissolution tank 30 is transferred to the separation device 28. Separation device 28 separates minor actinide 12, uranium and plutonium 10 and fission product 11 from solution 9.

Although the spent fuel processing apparatus of the present embodiment includes the heat exchanger 33, the refrigerant 34 may be supplied to the heat exchanger 33. An example of supplying the refrigerant 34 to the heat exchanger 33 will be described. When an abnormality such as an earthquake occurs during the operation of dissolving the fluoride residue 7 in the ionic liquid 8 in the dissolution tank 30 and the pipe connected to the dissolution tank 30 is broken, the solution 9 is considered to be at risk of leaking. On the other hand, in Table 1, the ionic liquid of a combination of imidazolium and chloride ions having the highest solubility of cerium fluoride has a melting point near room temperature. Therefore, in particular, when an ionic liquid having such a melting point near room temperature is used as a solvent, the solution 9 is cooled and solidified by supplying the refrigerant 34 to the heat exchanger 33 when an earthquake occurs. Even when an abnormality such as a broken pipe is detected, the solution 9 can be retained in the dissolution tank 30 and leakage to the outside can be prevented.

By using the spent fuel processing apparatus of this embodiment, it becomes possible to easily separate the actinide from the spent fuel.

Since the spent fuel processing apparatus of the present embodiment is configured to include the heat exchanger 33 in the dissolution tank 30, the solution 9 can be solidified in an emergency and the risk of liquid leakage can be eliminated.

The spent fuel processing apparatus of this embodiment converts the spent fuel into fluoride and dissolves the spent fuel component in the ionic liquid by dissolving the fluoride in the ionic liquid. It can be made easy.

As a comparative example 2, a method in which spent fuel is reacted with fluorine gas, solid fluoride is dissolved in a molten salt, and elements are separated by electrolysis as disclosed in Japanese Patent Application Laid-Open No. 2010-127616. When comparing the comparative example 2 and the method for separating the minor actinides according to the present embodiment, in the comparative example 2, the temperature of the dissolution step generally needs to be several hundred degrees Celsius. Since it can melt | dissolve near, according to a present Example, the effect that the temperature of a melt | dissolution process can be made low can be acquired.

1 .. fluoride Step 2 · dissolving step 3 · separating step 4 .. spent fuel 5 ... fluorine gas 6 .. UF ₆ gas 7 .. fluoride residue 8 ... ionic liquid 9 ... Solution 10 ..Uranium (U) and plutonium (Pu)
11. Fission product 12. Minor actinide 13. Frame 20. Flame furnace 21. Residue receiving and melting tank 22. Valve A
23. Valve B
24. Valve C
25. Valve D
26 ・・ Pump 27 ・・ Valve E
28 .. Separation device 30 .. Melting tank 31 .. Valve F
32. Valve G
33 ... Heat exchanger 34 ... Refrigerant

Claims

In a separation method for separating actinides from spent fuel using an ionic liquid,
Reacting the spent fuel with a fluorinating agent to produce a solid fluoride;
Dissolving the produced solid fluoride in an ionic liquid;
A method for separating actinides, comprising separating actinides from a solution in which the solid fluoride is dissolved in an ionic liquid.
The method for separating actinides according to claim 1, wherein the solid fluoride is dissolved in the ion solution after adjusting the temperature of the ion solution.
The method for separating actinides according to claim 1 or 2, wherein a solution obtained by dissolving the solid fluoride in an ionic solution is stirred.
4. The actinide separation method according to claim 1, wherein when an abnormality is detected, a solution obtained by dissolving the solid fluoride in an ionic solution is cooled.
A fluorination treatment apparatus for producing a solid fluoride by reacting a fluorinating agent with spent fuel;
A dissolution tank for producing a solution in which the solid fluoride is dissolved in an ionic liquid;
A spent fuel processor comprising a separator for separating actinides from the solution.
The dissolution tank functions as a receiving tank for collecting the solid fluoride,
The spent fuel processing apparatus according to claim 5, wherein the dissolution tank has an inlet for injecting the ionic liquid, and is configured to accumulate the ionic liquid in the dissolution tank.
The spent fuel processing apparatus according to claim 5 or 6, wherein the dissolution tank has a heat exchanger for adjusting a temperature of the ionic liquid.
The spent fuel processing device according to any one of claims 5 to 7, wherein the dissolution tank includes a stirring device for stirring a solution obtained by dissolving the solid fluoride in an ionic liquid.
The spent fuel processing apparatus according to claim 7 or 8, wherein the heat exchanger cools a solution obtained by dissolving the solid fluoride in an ionic liquid.