Radionuclide production system and radionuclide production method

Abstract

To provide a radioactive nuclide producing system and a radioactive nuclide producing method capable of safely producing a radioactive nuclide by suppressing leakage of a gaseous radioactive substance.SOLUTION: A radioactive nuclide producing system for producing radioactive nuclides by irradiating a liquid or solid containing a raw material nuclide with bremsstrahlung radiation generated by irradiation with an electron beam, wherein a container 10 housing a liquid or solid containing at least one of a raw material nuclide and a raw material nuclide produced by the irradiation of the bremsstrahlung from the raw material nuclide is provided, the container 10 comprises a gas permeable material 11 permeable to gases depending on the molecular size, and a connection 12 that is connected in a closed system with a corresponding connection portion. The radionuclide production method includes an irradiation treatment for irradiating bremsstrahlung with raw material nuclides and a separation and purification treatment for separating and purifying the produced nuclides, in the irradiation treatment and separation and purifying treatment, a liquid or a solid including at least one of the raw material nuclide and generated nuclide is handled in a state accommodated in the container 10.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a radionuclide production system and a radionuclide production method in which a radionuclide production process is carried out with source nuclides and product nuclides contained in semi-sealed containers.

[0002] Actinium-225 (Ac-225) is a radioactive nuclide that emits alpha rays, and is expected to be a raw material for therapeutic drugs used in alpha-particle therapy. Conventionally, actinium-225 (Ac-225) is produced by the decay of its parent nuclide, thorium-229 (Th-229).

[0003] Currently, there are only three facilities capable of supplying clinically-ready Ac-225: the Institute for Transuranium Elements (ITU) in Karlsruhe, Germany, Oak Ridge National Laboratory (ORNL) in the United States, and the Institute of Physics and Power Engineering (IPPE) of the Russian National Scientific Center in Obninsk, Russia.

[0004] Th-229 does not exist in nature, but is produced by decay of uranium 233 (U-233). However, since U-233 will no longer be produced in the future due to nuclear material protection, the amount of AC-225 that can be produced worldwide will be limited to the amount that can be produced from existing U-233 via Th-229. This amount is sufficient for preclinical testing, but it is expected to be significantly insufficient after clinical trials. Therefore, it is desirable to produce AC-225 using an accelerator.

[0005] A known method for producing Ac-225 using an accelerator is to use the Ra-226(p,2n)Ac-225 reaction. In this method, naturally occurring radium-226 (Ra-226) is irradiated with protons accelerated by a cyclotron. Production tests are being conducted at ORNL, Brookhaven National Laboratory (BNL) in the United States, and the National Institutes for Quantum and Radiological Science and Technology (QST) in Japan, but it has not yet been commercialized.

[0006] The method of producing Ac-225 using an accelerator has manufacturing problems. Protons accelerated by a cyclotron have a short range in Ra-226, so even if the target is made thick, it is not possible to mass-produce Ac-225. Most of the proton energy is lost in the target, but it is difficult to sufficiently remove heat from the target, so it is difficult to increase the accelerator beam current and energy compared to conventional methods.

[0007] As a method for producing Ac-225 using an accelerator, there is a method in which Ra-226(γ,n)Ra-225 reaction is followed by beta decay of Ra-225 to convert it into Ac-225. In this method, bremsstrahlung radiation is irradiated to Ra-226. Bremsstrahlung radiation is generated by irradiating a heavy metal target with electrons accelerated by a microtron or linear accelerator. Patent Document 1 describes a technology for producing radioactive nuclides by irradiating a fluid containing raw material nuclides in a circulation path with bremsstrahlung radiation. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2020-183926 A Summary of the Invention [Problem to be solved by the invention]

[0009] In the radionuclide production process, the source nuclide is irradiated with bremsstrahlung radiation or the like to induce a nuclear reaction, and the source nuclide is transformed into a specified product nuclide to produce the desired radionuclide. The source nuclide and the product nuclide produced by the nuclear reaction of the source nuclide may undergo radioactive decay to produce a gaseous radioactive nuclide. Since gaseous radioactive materials are prone to diffusion and leakage into the surroundings, a production process in which the source nuclide and product nuclide are handled in a container is desired.

[0010] When producing radionuclides, it is necessary to carry out processes such as irradiation, in which the raw nuclide is irradiated with bremsstrahlung radiation, and separation and purification, in which the produced nuclide is separated and purified from the raw nuclide. If these processes can be carried out while the raw nuclide and the produced nuclide are contained in containers, the risks of radioactive contamination and exposure can be reduced. Since the equipment for removing radioactive materials and the equipment for shielding radiation can be simplified, it is expected that the manufacturing equipment can be made smaller and less expensive.

[0011] However, there is a risk that the internal pressure of the containers used to handle the source nuclides and the produced nuclides will rise significantly due to the generation of gaseous radioactive nuclides and heating inside the container. If the internal pressure rises excessively, the container may break, and radioactive materials may diffuse or leak into the surrounding area. There is a demand for a manufacturing process that can perform various processes while keeping the source nuclides and the produced nuclides inside the container while suppressing the internal pressure of the container.

[0012] In the technology described in Patent Document 1, a fluid containing source nuclides and produced nuclides is circulated in a circulation path, but since the circulation path is a closed system, measures are required to prevent an increase in internal pressure. In addition, while the fluid containing source nuclides can be used as a raw material, there is a problem that the solid cannot be used as a raw material. It is also expected that there will be cases where it is required to produce the target radioactive nuclide in a smaller production unit.

[0013] Therefore, an object of the present invention is to provide a radionuclide production system and a radionuclide production method that are capable of safely producing radionuclides by suppressing leakage of gaseous radioactive materials. [Means for solving the problem]

[0014] In order to solve the above problems, the radionuclide production system of the present invention is a radionuclide production system that produces a radionuclide by irradiating a liquid or solid containing a source nuclide with bremsstrahlung radiation generated by irradiation with an electron beam, and includes a container that contains a liquid or solid containing at least one of the source nuclide and a product nuclide generated from the source nuclide by irradiating it with the bremsstrahlung radiation, and the container has a gas permeable material that forms a part of a main body of the container and allows gas to pass therethrough depending on the size of the molecule, and a connection part that is provided in the main body of the container and is connected to a corresponding other connection part in a closed system to enable the flow of a fluid.

[0015] Furthermore, a radionuclide production method according to the present invention is a radionuclide production method for producing a radionuclide by irradiating a liquid or solid containing a source nuclide with bremsstrahlung generated by irradiation with an electron beam, the method comprising: an irradiation process for irradiating the source nuclide with bremsstrahlung; and a separation and purification process for separating and purifying a product nuclide generated from the source nuclide by the irradiation with the bremsstrahlung; in the irradiation process and the separation and purification process, the source nuclide and the liquid or solid containing at least one of the product nuclide are handled in a state of being contained in a container, the container having a gas permeable material that forms a part of a main body of the container and allows gas to pass therethrough depending on the size of the molecule, and a connection part that is provided in the main body of the container and is connected to a corresponding other connection part in a closed system to enable the flow of a fluid. Effect of the Invention

[0016] According to the present invention, it is possible to provide a radionuclide production system and a radionuclide production method capable of safely producing radionuclides by suppressing leakage of gaseous radioactive materials. [Brief description of the drawings]

[0017] [Figure 1] FIG. 2 is a diagram showing an example of a container used in the radionuclide production system according to the present embodiment. [Diagram 2] FIG. 2 is a diagram showing an example of a container used in the radionuclide production system according to the present embodiment. [Diagram 3] FIG. 1 illustrates an example of a process for handling containers in a radionuclide production system. [Figure 4] FIG. 1 illustrates an example of a process for handling containers in a radionuclide production system. [Diagram 5] FIG. 1 illustrates an example of a process for handling containers in a radionuclide production system. [Figure 6] FIG. 1 illustrates an example of a process for handling containers in a radionuclide production system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, a radionuclide production system and a radionuclide production method according to an embodiment of the present invention will be described with reference to the drawings. In the following drawings, common components are designated by the same reference numerals and duplicated explanations will be omitted.

[0019] The radionuclide production system according to this embodiment is a system for producing a radionuclide by irradiating a liquid containing a source nuclide or a solid containing a source nuclide with bremsstrahlung radiation generated by irradiation with an electron beam. In this radionuclide production system, a predetermined source nuclide is irradiated with bremsstrahlung radiation having an energy equal to or greater than the threshold of a nuclear reaction, and the source nuclide is nuclear-transformed into a predetermined product nuclide by a nuclear reaction caused by the bremsstrahlung radiation to produce a target radionuclide.

[0020] In the radionuclide production system according to the present embodiment, a radionuclide production process is carried out while chemical species including source nuclides and chemical species including product nuclides produced by nuclear reactions from source nuclides are contained in a semi-sealed container. Liquid chemical species may be contained in the semi-sealed container, or solid chemical species may be contained in the semi-sealed container. At least one of source nuclides and product nuclides is contained in the semi-sealed container depending on the progress of the production process.

[0021] The radionuclide production process in the radionuclide production system is carried out in the following manner. Raw materials in an appropriate chemical form, including the raw material nuclide, are contained in a semi-sealed container. The container containing the raw materials is then placed in an irradiation section for irradiation treatment. The irradiation section is a site where electron beam irradiation is carried out, and is provided within the radionuclide production system. The irradiation treatment is a process in which bremsstrahlung is generated by irradiation with an electron beam, and the raw material nuclide is irradiated with bremsstrahlung radiation.

[0022] In the irradiation process, a high-energy electron beam is irradiated from an electron beam irradiation device toward an irradiation section. The electron beam is irradiated onto a target material for generating bremsstrahlung. The target material for generating bremsstrahlung may be disposed in the irradiation section or may be provided integrally with a semi-sealed container. When irradiated with an electron beam of a predetermined energy, the target material for generating bremsstrahlung generates bremsstrahlung having energy equal to or greater than a threshold required for a nuclear reaction of the source nuclide. The bremsstrahlung is irradiated onto a source material containing the source nuclide contained in a semi-sealed container.

[0023] When the irradiation process is performed, the source nuclide is irradiated with bremsstrahlung radiation, causing a nuclear reaction, and the source nuclide is transformed to generate a predetermined product nuclide. The semi-sealed container that has been irradiated is then transported from the irradiation section to the separation and purification section where the separation and purification process is performed. The separation and purification section is a section where the target radioactive nuclide is recovered, and is provided in the radioactive nuclide production system. The separation and purification process is a process in which the product nuclide generated from the source nuclide by irradiation with bremsstrahlung radiation is separated and purified from the source nuclide, etc.

[0024] In the separation and purification process, a target radionuclide is recovered in an appropriate chemical form from chemical species including source nuclides and product nuclides contained in a semi-sealed vessel. The target radionuclide to be recovered may be a daughter nuclide produced by a nuclear reaction of the source nuclide, or a progeny nuclide produced by radioactive decay of the daughter nuclide after the nuclear reaction of the source nuclide.

[0025] As the raw material nuclide, an appropriate nuclide can be used depending on the radioactive nuclide to be produced. Specific examples of raw material nuclides include radium-226 (Ra-226), molybdenum-100 (Mo-100), zinc-68 (Zn-68), hafnium-178 (Hf-178), germanium-70 (Ge-70), etc.

[0026] As the nuclear reaction for nuclear transmutation of the source nuclide, appropriate photonuclear reactions such as (γ,n), (γ,p), (γ,2n), (γ,pn), etc. can be used depending on the radioactive nuclide to be produced, the type of source nuclide, the required energy, etc.

[0027] There is no particular limitation on the radionuclide produced by the radionuclide production system 1. As the radionuclide to be produced, an α-ray emitting nuclide, a β-ray emitting nuclide, or a γ-ray emitting nuclide is preferred, and an α-ray emitting nuclide is particularly preferred, because they are useful as raw materials for therapeutic drugs used in RI internal therapy, radioactively labeled reagents used in radiodiagnosis, and the like.

[0028] For example, to produce the alpha-emitting nuclide actinium-225 (Ac-225), the Ra-226(gamma,n)Ra-225 reaction and the beta decay of Ra-225 can be used. Raw materials containing the raw nuclide can be solids such as radium chloride (RaCl2) and radium carbonate (RaCO3) containing radium-226 (Ra-226), or liquids such as nitric acid solutions and aqueous solutions in which these are dissolved.

[0029] The radionuclide production system may include an electron beam generator that includes a radiation source that generates electrons and an accelerator that accelerates the electrons as a device for generating an electron beam for generating bremsstrahlung radiation. The accelerator is preferably a linear accelerator. The electron linear accelerator can be made smaller in size than a proton accelerator or a heavy particle accelerator if the same energy is applied.

[0030] When nuclear reactions caused by bremsstrahlung are used to produce radioactive nuclides, incident particles with the energy required for the nuclear reaction can be generated in a smaller accelerator than with synchrotrons, cyclotrons, etc. Also, compared to using nuclear reactions caused by neutrons or charged particles, thick shielding is not required, so the equipment can be made smaller.

[0031] Conventionally, a method of producing Ac-225 using an accelerator is known to utilize the Ra-226(p,2n)Ac-225 reaction. The reaction cross section of the Ra-226(γ,n)Ra-225 reaction is comparable to that of the Ra-226(p,2n)Ac-225 reaction. When an electron linear accelerator is used, components other than the accelerator can also be made smaller than when a proton accelerator is used.

[0032] A method for producing Ac-225 using an accelerator is also known in which the Ra-226(n,2n)Ra-225 reaction is followed by beta decay of Ra-225 to convert it into Ac-225. The cross section of the Ra-226(n,2n)Ra-225 reaction is slightly less than one order of magnitude larger than that of the Ra-226(γ,n)Ra-225 reaction.

[0033] However, in this method, in order to cause a reaction with fast neutrons, it is necessary to irradiate a carbon target or a metal target with tritium absorbed, with deuterons accelerated by a cyclotron. Since shielding of the fast neutrons is necessary, the problem of the system becoming large due to the thick shielding material. In addition, since a large amount of fast neutrons is generated, the radioactivity of the device itself becomes significant.

[0034] In contrast, when using the Ra-226(γ,n)Ra-225 reaction and the beta decay of Ra-225, bremsstrahlung is generated by irradiating the target material for generating bremsstrahlung with an electron beam, making shielding easier. Electron beams and bremsstrahlung radiation can be shielded more easily than fast neutrons, etc., making it possible to miniaturize the system compared to methods that use other nuclear reactions.

[0035] Ra-225 undergoes beta decay and becomes Ac-225 with a half-life of 14.8 days. Ac-225 is an alpha-particle-emitting nuclide useful as a raw material for therapeutic drugs. Ac-225 becomes Fr-221 with a half-life of 10.0 days. Fr-221 becomes At-217 with a half-life of 4.9 minutes. At-217 becomes Bi-213 with a half-life of 32 milliseconds. These progeny nuclides are also alpha-particle-emitting nuclides and can be used as raw materials for therapeutic drugs.

[0036] Ra-226 and Ra-225 are not alpha-emitting nuclides, and therefore are not necessary as raw materials for therapeutic drugs. It is preferable to separate the Ra-226 and Ra-225 remaining after the irradiation process from alpha-emitting nuclides such as Ac-225. In addition, since Ra-226 is relatively expensive, it is preferable to reuse it as a raw material nuclide. In the separation and purification process, in addition to the target radioactive nuclide, such unnecessary radioactive nuclide is separated from the unreacted raw material nuclide.

[0037] Ra-226 undergoes alpha decay and becomes Rn-222 with a half-life of 1600 years. Rn-222 is a radioactive nuclide that exists as a gas with a boiling point of -61.7°C. When Rn-222 diffuses into the environment, Rn-222 and its progeny nuclides attach to it, causing radioactive contamination. Since it is preferable not to release such gaseous radioactive materials into the environment during the production of radioactive nuclides, it is desirable to store liquids or solids containing the raw nuclides and the produced nuclides in sealed containers and handle them in a closed system.

[0038] However, when using a liquid as a source containing the source nuclide, there are problems with handling it in a completely closed system. When a liquid is irradiated with bremsstrahlung radiation, if the liquid contains water, radiolysis of the water occurs, producing oxygen gas and hydrogen gas. When using the Ra-226(γ,n)Ra-225 reaction and the β decay of Ra-225, radiolysis of water also occurs due to α rays emitted by Ac-225 and its progeny nuclides.

[0039] When liquids or solids containing source nuclides or product nuclides are stored and handled in a sealed container, if oxygen gas or hydrogen gas is generated by radiolysis of water, gas will accumulate inside the sealed container. If a large amount of gas accumulates, the internal pressure of the sealed container will increase, which may cause the sealed container to break and radioactive materials to leak. In addition, when liquids containing source nuclides or product nuclides are heated by bremsstrahlung radiation, the liquid will vaporize, which may also cause the internal pressure of the sealed container to increase.

[0040] When 50 GBq of Ra-226 is used as the source nuclide, alpha decay produces 5.0 × 10 10 1000 units of Rn-222 are produced. Rn-222 undergoes alpha decay with a half-life of 3.8 days. The progeny nuclides of Rn-222 may not be gaseous. Therefore, the amount of gas produced by Ra-226 is very small. However, when an aqueous solution is stored in a sealed container, the amount of gas produced by the radiolysis of water is large. If the sealed container is damaged by the radiolysis of water, even a small amount of radioactive material will be released into the environment. Gaseous radioactive material is likely to disperse in the environment, and there is a risk of widespread radioactive contamination.

[0041] On the other hand, when a solid is used as a source material containing a source nuclide, radiolysis of water does not occur, and therefore oxygen gas or hydrogen gas is not generated. However, when bremsstrahlung radiation is irradiated, the sealed container and the solid are heated, and the internal pressure of the sealed container may increase. If a cover gas such as helium or nitrogen is sealed in the sealed container, the cover gas expands, and the internal pressure of the sealed container is likely to increase.

[0042] In contrast, in the radionuclide production system according to the present embodiment, liquids or solids containing source nuclides or produced nuclides are handled in a semi-sealed container. A gas-permeable material that allows gas to pass through depending on the size of the molecule is used for the semi-sealed container. Therefore, it is possible to suppress the release of large molecules generated by nuclear reactions or radioactive decay to the outside of the container, while allowing small molecules that tend to affect the internal pressure of the container to be released to the outside of the container. Therefore, it is possible to suppress the increase in the internal pressure of the container and prevent the leakage of radioactive materials.

[0043] 1 and 2 are diagrams showing an example of a container used in the radionuclide producing system according to this embodiment. 1 and 2 show a semi-sealed container 10 used in a radioactive nuclide production system with a perspective view of the inside. 1 and 2 show the state of the container 10 during irradiation treatment in which a raw nuclide is irradiated with bremsstrahlung radiation.

[0044] As shown in Figures 1 and 2, the semi-sealed container 10 has a gas-permeable material 11 that allows gas to pass through depending on the size of the molecules, a connection part 12 that is connected to another corresponding connection part in a closed system to enable the flow of fluid, and a bremsstrahlung radiation generating part 13 that generates bremsstrahlung radiation when irradiated with an electron beam.

[0045] In Fig. 1, a container 10 contains a liquid 30. A solution in which chemical species in an appropriate chemical form including source nuclides are dissolved is prepared as the liquid 30. After the irradiation process, the liquid 30 becomes a mixture of chemical species including product nuclides generated by irradiation with bremsstrahlung radiation, chemical species including unreacted source nuclides, and chemical species including progeny nuclides generated by radioactive decay of these.

[0046] 2, a solid 31 is contained in a container 10. A powder, bulk, or the like of a chemical species in an appropriate chemical form containing a source nuclide is prepared as the solid 31. After the irradiation process, the solid 31 is in a state in which chemical species containing product nuclides generated from the source nuclide by irradiation with bremsstrahlung, chemical species containing unreacted source nuclide, and chemical species containing progeny nuclides generated by radioactive decay of these are mixed together.

[0047] Gas 32 exists on liquid 30 and solid 31 in container 10. Helium, nitrogen, etc., which function as a cover gas or coolant, are enclosed as gas 32. After irradiation processing, gas 32 becomes a mixture of gaseous radioactive nuclides produced by radioactive decay of source nuclides and product nuclides, oxygen gas and hydrogen gas produced by radiolysis of water, water vapor vaporized by heating, etc.

[0048] The semi-sealed container 10 shown in Figures 1 and 2 is used in a manufacturing process for producing radioactive nuclides. The liquid 30 or solid 31 undergoes various treatments while still contained in the container 10. Such treatments include a treatment for preparing the liquid 30 or solid 31 of a chemical species containing the source nuclide, an irradiation treatment for irradiating the source nuclide with bremsstrahlung radiation, a separation and purification treatment for separating and purifying the produced nuclide from the source nuclide, transportation of the liquid 30 or solid 31 within the system, and recovery of the radioactive nuclides.

[0049] The semi-sealed container 10 can be transported automatically or manually within the system. The automatic transport can be performed by an appropriate automatic transport device such as a robot arm or a conveyor. The semi-sealed container 10 is also connected automatically or manually to other corresponding devices such as containers, columns, piping, etc. The automatic connection can be performed by an appropriate device such as a robot arm or an automatic capping machine.

[0050] In the irradiation process of irradiating the source nuclide with bremsstrahlung, the electron beam 1 is irradiated from below the vessel 10 toward the bremsstrahlung generator 13. When irradiated with the electron beam 1, the bremsstrahlung generator 13 generates bremsstrahlung and irradiates the liquid 30 or solid 31 containing the source nuclide with the bremsstrahlung. The source nuclide undergoes a nuclear reaction and is nuclear-transformed into a predetermined product nuclide.

[0051] The container 10 has a main body that separates the inside of the container from the outside of the container. A part of the main body of the container 10 is formed of a gas permeable material 11. The main body of the container 10 is provided with a connection part 12 having a through hole that communicates between the inside of the container and the outside of the container. In Fig. 1 and Fig. 2, the main body of the container 10 is formed in a hollow cylindrical shape. However, the main body of the container 10 can be formed in any suitable shape such as a hollow cube, a hollow rectangular parallelepiped, a hollow polygonal prism, or the like.

[0052] The gas permeable material 11 is formed of a material that functions as a molecular sieve that allows gas to pass through depending on the size of the molecule. The gas permeable material 11 can be a porous material having pores that allow small molecules such as oxygen, hydrogen, water vapor, helium, nitrogen, carbon dioxide, hydrogen chloride, and nitric acid to pass through, while preventing large molecules such as radon from passing through. The gas permeable material 11 can suppress the internal pressure of the container 10 by allowing small molecules to be released outside the container 10 while suppressing the release of large molecules outside the container 10.

[0053] The molecular size of radon is approximately 0.6 nm. The molecular size of oxygen molecules is approximately 0.35 nm. The molecular size of hydrogen molecules is approximately 0.28 nm. The molecular size of water molecules is approximately 0.38 nm. The molecular size of helium molecules is approximately 0.26 nm. The molecular size of nitrogen molecules is approximately 0.36 nm. The molecular size of carbon dioxide molecules is approximately 0.33 nm.

[0054] It is preferable to use a material that allows molecules less than 0.5 nm in size to pass through and does not allow molecules 0.5 nm or more in size to pass through as the gas permeable material 11. By using such a material, it is possible to confine large molecules such as Rn-222 inside the container 10 while releasing small molecules such as oxygen, hydrogen, water vapor, helium, and nitrogen that tend to affect the internal pressure of the container 10 to the outside of the container 10. The internal pressure of the container 10 is suppressed, and damage to the container 10 is prevented, thereby suppressing leakage of radioactive materials.

[0055] A material in which zeolite is supported on a porous support can be used as the gas permeable material 11. As long as the surface area and mechanical strength are ensured, a monolithic or sheet-shaped sintered body, a foam, or the like can be used as the support. Examples of materials for the support include inorganic materials such as alumina, silica, zirconia, titania, silicon nitride, and silicon carbide, and metal materials such as stainless steel, iron, nickel, tungsten, and alloys of these materials.

[0056] Gas permeable material 11 can be formed, for example, by a method in which zeolite seed crystals are attached to a porous support, and then the support is immersed in a solution containing an aluminum raw material, a silicon raw material, an alkali raw material, etc., to hydrothermally synthesize zeolite in the solution. There are no particular limitations on the thickness of gas permeable material 11, the thickness of the zeolite membrane, and the particle size of the zeolite, as long as the surface area and mechanical strength are ensured and the permeation of large molecules is prevented.

[0057] 1 and 2, the gas permeable material 11 forms the upper surface of the main body of the container 10 excluding the connection part 12. The gas permeable material 11 is provided as a ring-shaped member around the connection part 12. When the gas permeable material 11 is provided on the upper surface of the main body of the container 10, small molecules on the liquid 30 and the solid 31 can be efficiently released to the outside of the container 10. However, the gas permeable material 11 can be provided in an appropriate shape at an appropriate location, such as the side surface of the main body of the container 10, in addition to the upper surface of the main body of the container 10.

[0058] The connection part 12 is provided in a structure that allows connection to the connection part of the corresponding other container, piping, or other equipment in a closed system without exposing the inside of the through hole to the outside air. The connection part 12 allows two-way flow of fluid between the container 10 and the other equipment when connected to the connection part of the corresponding other equipment. A liquid used for producing radioactive nuclides can be introduced into the container 10 or discharged out of the container 10 through the connection part 12.

[0059] It is preferable that the connection part 12 is provided in a structure in which, when the connection part of the corresponding other device is connected, the through hole is open and the fluid can flow, and when the connection part of the corresponding other device is not connected, the through hole is closed and the fluid cannot flow. With such a structure, the introduction and discharge of the liquid 30 and the airtightness of the container 10 can be controlled by the operation of connecting the connection parts, so that the handling of the container 10 can be easily automated.

[0060] The connection part 12 can be formed of a through hole that communicates between the inside and outside of the container, a connector that can be coupled to a corresponding connector, a sealant that airtightly seals the through hole, etc. The connector of the connection part 12 of the container 10 is provided so that it can be coupled to a corresponding connector provided on another device. The connector is provided in a structure that includes a coupling body that seals the through hole when they are coupled to each other. The connection part 12 can include an appropriate mechanism such as a spring type, pressure type, or clamp type mechanism for opening and closing the through hole and for releasing the biasing force on the check valve provided in the through hole.

[0061] 1 and 2, the connection part 12 protrudes upward in a tubular shape from the center of the upper surface of the main body of the container 10. However, as long as the connection part 12 can introduce and discharge the liquid 30, it can be provided in an appropriate shape at an appropriate location, such as on the side surface of the main body of the container 10 or the lower surface of the main body of the container 10, in addition to the upper surface of the main body of the container 10.

[0062] The bremsstrahlung generating unit 13 is made of a heavy metal that generates bremsstrahlung radiation when irradiated with an electron beam. If the bremsstrahlung generating unit 13 is provided integrally as part of the main body of the vessel 10, the liquid 30 or solid 31 contained in the vessel 10 can be directly irradiated with bremsstrahlung radiation, so that the source material nuclides can undergo a nuclear reaction with high uniformity. In addition, the end of the range of the electron beam 1 can be set inside the vessel 10, making it easy to shield the electron beam 1.

[0063] A heavy metal having a large atomic number and high density can be used as the material of the bremsstrahlung radiation generating unit 13. Examples of the material of the bremsstrahlung radiation generating unit 13 include tungsten (W), tantalum (Ta), lead (Pb), bismuth (Bi), and platinum group metals such as platinum (Pt), rhodium (Rh), palladium (Pd), ruthenium (Ru), and iridium (Ir).

[0064] 1 and 2, the bremsstrahlung generating unit 13 forms the bottom surface of the main body of the vessel 10. If the bremsstrahlung generating unit 13 is provided on the bottom surface of the main body of the vessel 10, the liquid 30 at the bottom is heated when the electron beam 1 is irradiated, and therefore the liquid 30 can be naturally convected to cause a highly uniform nuclear reaction. However, the bremsstrahlung generating unit 13 can be provided in a suitable shape at a suitable location, such as on the top surface of the main body of the vessel 10, on a side surface of the main body of the vessel 10, or between the vessel 10 and the electron beam generator, as long as the source nuclide is irradiated with bremsstrahlung.

[0065] As shown in Fig. 1, when liquid 30 is contained in container 10, if liquid 30 contains water, radiolysis of water occurs due to bremsstrahlung radiation or radiation emitted by radioactive nuclides. Oxygen gas or hydrogen gas is generated, and the internal pressure of container 10 may increase. In addition, liquid 30 or gas 32 is heated by the incidence of bremsstrahlung radiation or electron beam 1. If liquid 30 vaporizes, the internal pressure of container 10 may increase.

[0066] 2, when a solid 31 is contained in the container 10, radiolysis of water does not occur due to bremsstrahlung radiation or radiation emitted by radioactive nuclides. However, the solid 31 and gas 32 are heated by the incidence of the electron beam 1. When the gas 32 is heated, the gas 32 expands, and there is a risk that the internal pressure of the container 10 will increase.

[0067] However, as shown in Figures 1 and 2, when a gas permeable material 11 is used in a part of the main body of the container 10, large molecules of radioactive substances such as Rn-222 generated in the liquid 30 or solid 31 can be trapped inside the container 10. Oxygen and hydrogen generated by radiolysis of water, water vapor evaporated by heating, helium and nitrogen sealed as cover gas, and small molecules such as carbon dioxide, hydrogen chloride, and nitric acid desorbed from the raw material liquid 30 or solid 31 can be released to the outside of the container 10. This makes it possible to suppress an increase in the internal pressure of the container and prevent leakage of radioactive substances.

[0068] FIG. 3 is a diagram showing an example of a process for handling containers in a radionuclide production system. Fig. 3 shows a semi-sealed container 10 in which a drying process is performed to dry out chemical species containing the produced nuclides, as seen through the inside. As shown in Fig. 3, when a liquid 30 is used as a raw material containing raw material nuclides, the semi-sealed container 10 is subjected to an irradiation process in which the raw material nuclides are irradiated with bremsstrahlung radiation, and then to a drying process in which the chemical species containing the produced nuclides are dried out. The concentration of the produced nuclides is adjusted by removing the solvent contained in the liquid 30.

[0069] 3, a container 10 contains a liquid 30. The liquid 30 contains a solution containing product nuclides produced by irradiation with bremsstrahlung radiation. In the liquid 30, chemical species containing the product nuclides are mixed together with chemical species containing unreacted source nuclides and chemical species containing progeny nuclides produced by radioactive decay of the product nuclides.

[0070] Gas 32 exists above the liquid 30 in the vessel 10. Helium, nitrogen, etc., which function as a cover gas or coolant, are enclosed as the gas 32. The gas 32 may include gaseous radioactive nuclides produced by radioactive decay of the source nuclides and product nuclides, oxygen gas and hydrogen gas produced by radiolysis of water, water vapor vaporized by heating, etc.

[0071] As shown in Fig. 3, the radionuclide production system includes a heating unit 40 that heats the contents of a semi-closed container 10. The heating unit 40 can include an appropriate heating device such as a resistance heating device such as an electric furnace, an induction heating device, a microwave dielectric heating device, or a high-frequency dielectric heating device. The heating unit 40 performs a drying process (see Fig. 3) in which the liquid 30 containing the produced nuclide contained in the container 10 is heated and dried, and a process (see Figs. 4 to 6) in which the gas in the container 10 is heated and pressurized, and the liquid 30, etc. contained in the container 10 is discharged by the pressure of the gas 32.

[0072] The container 10 containing the liquid 30 containing the product nuclides is transported to the heating section 40 after the irradiation process in which the raw material nuclides are irradiated with bremsstrahlung radiation and before the separation and purification process in which the product nuclides are separated and purified from the raw material nuclides, and is subjected to a drying process in which the chemical species containing the product nuclides are dried.

[0073] In the drying process, the liquid 30 containing the produced nuclides contained in the container 10 is heated to dry out the chemical species containing the produced nuclides contained in the liquid 30 into a solid. The chemical species of the solvent contained in the liquid 30 are distilled off by heating. Some of the water vapor vaporized by heating and small molecules such as carbon dioxide, hydrogen chloride, and nitric acid desorbed from the raw liquid 30 permeate the gas permeable material 11 and are released to the outside of the container 10 together with the oxygen and hydrogen produced by radiolysis of water and the remaining small molecules such as helium and nitrogen sealed as cover gas. Large molecules such as radon and solids contained in the liquid 30 do not permeate the gas permeable material 11 and remain in the container 10.

[0074] The drying process may be performed under a pressure atmosphere equivalent to the internal pressure of the container 10, or under a pressure atmosphere lower than the internal pressure of the container 10. When the pressure is reduced to a pressure atmosphere lower than the internal pressure of the container 10, a transmembrane pressure difference is formed across the gas permeable material 11. This can promote the vaporization of the chemical species of the solvent contained in the liquid 30 and the release of small molecules through the gas permeable material 11.

[0075] FIG. 4 is a diagram showing an example of a process for handling containers in a radionuclide production system. Fig. 4 shows a semi-sealed container 10, which is subjected to a dissolution treatment for dissolving the dried chemical species containing the product nuclide, as seen through the inside. As shown in Fig. 4, the semi-sealed container 10 is subjected to a dissolution treatment for dissolving the chemical species containing the product nuclide after the drying treatment for drying the chemical species containing the product nuclide. A separation and purification treatment is performed by column chromatography by preparing a solution of the chemical species containing the product nuclide.

[0076] In Fig. 4, a solid 31 is contained in a container 10. The solid 31 is a dried material such as a sludge or powder made by drying chemical species containing product nuclides produced by irradiation with bremsstrahlung. The solid 31 contains a mixture of chemical species containing product nuclides, chemical species containing unreacted source nuclides, and chemical species containing progeny nuclides produced by radioactive decay of these, in addition to chemical species containing product nuclides.

[0077] A dissolving solution 33 prepared to a predetermined concentration and a predetermined amount is contained in the container 20. As the dissolving solution 33, a nitric acid solution, a hydrochloric acid solution, water, or the like for dissolving chemical species including the produced nuclides is contained.

[0078] Similar to the container 10, the container 20 has a gas permeable material 11 that allows gas to pass through depending on the size of the molecules, and a connection part 12 that is connected to a corresponding other connection part in a closed system to enable the flow of fluid. Similar to the container 10, the container 20 may be provided in a structure that has a bremsstrahlung radiation generating part 13, or may be provided in a structure that does not have a bremsstrahlung radiation generating part 13. The connection part 12 of the container 20 and the connection part 12 of the container 10 are provided so as to be connectable to each other in a closed system.

[0079] Gas 32 exists on solid 31 in container 10 and on dissolution liquid 33 in container 20. Helium, nitrogen, or the like that functions as a cover gas is enclosed as gas 32. Gas 32 on solid 31 in container 10 may include gaseous radioactive nuclides produced by radioactive decay of source nuclides and product nuclides, oxygen gas and hydrogen gas produced by radiolysis of water, water vapor vaporized by heating, and the like.

[0080] As shown in Fig. 4, the radionuclide production system includes a vibration unit 50 that vibrates the semi-sealed container 10. The vibration unit 50 is disposed below the heating unit 40. The vibration unit 50 may include an appropriate vibration device such as an eccentric motion type, a reciprocating motion type, or an ultra-vibration type. The vibration unit 50 vibrates the container 10 to perform a process of stirring the liquid 30 contained in the container 10 (see Fig. 4).

[0081] The container 10 containing the solid 31 containing the dried product nuclide is transported to the vibration section 50 and subjected to a dissolution process for dissolving the chemical species containing the product nuclide, after the irradiation process for irradiating the raw material nuclide with bremsstrahlung radiation and before the separation and purification process for separating and purifying the product nuclide from the raw material nuclide. A container 20 containing a dissolution liquid 33 is transported above the container 10 containing the solid 31. The container 20 containing the dissolution liquid 33 is placed upside down above the container 10 containing the solid 31. The connection section 12 of the container 10 containing the solid 31 is connected to the connection section 12 of the container 20 containing the dissolution liquid 33.

[0082] In the dissolution process, the gas 32 in the container 20 containing the dissolution liquid 33 is heated and pressurized by the heating unit 40, and the dissolution liquid 33 contained in the container 20 is discharged from the connection part 12 of the container 20 by the pressure of the gas 32. The gas 32 expands when heated, and pushes the dissolution liquid 33 contained in the container 20 toward the container 10 containing the dried solid 31. Helium and nitrogen sealed in the container 10 as cover gases and some of the small molecules remaining in the container 10 permeate the gas permeable material 11 and are released to the outside of the container 10. Large molecules such as radon remaining in the container 10 do not permeate the gas permeable material 11 and remain in the container 10.

[0083] The container 10 containing the dried solid 31 is introduced with the dissolving liquid 33 and is vibrated by the vibration unit 50. The solid 31 is dissolved in the dissolving liquid 33 as the dissolving liquid 33 is stirred by the vibration. When the dissolving process is performed after the drying process, the chemical species including the produced nuclides can be redissolved in a predetermined concentration and a predetermined amount of the dissolving liquid 33, so that a solution of a predetermined concentration to be subjected to a separation and purification process by column chromatography is obtained.

[0084] FIG. 5 is a diagram showing an example of a process for handling containers in a radionuclide production system. Fig. 5 shows a perspective view of the inside of a semi-sealed vessel 10 undergoing an adsorption treatment for adsorbing the produced nuclides to a stationary phase, which is one of the separation and purification treatments for separating and purifying the produced nuclides from the raw nuclides. As shown in Fig. 5, the semi-sealed vessel 10 undergoes a dissolution treatment for dissolving chemical species including the produced nuclides, and then an adsorption treatment for adsorbing the produced nuclides to a stationary phase.

[0085] In Fig. 5, the upper container 10 contains a liquid 30. The liquid 30 contains a solution in which chemical species including product nuclides produced by irradiation with bremsstrahlung are dissolved in a dissolution liquid 33. The liquid 30 contains a mixture of chemical species including product nuclides, chemical species including unreacted source nuclides, and chemical species including progeny nuclides produced by radioactive decay of these.

[0086] A gas 32 exists above the liquid 30 in the upper container 10. Helium, nitrogen, or the like that functions as a cover gas is enclosed as the gas 32. The gas 32 may include gaseous radioactive nuclides produced by radioactive decay of the source nuclides and product nuclides, oxygen gas and hydrogen gas produced by radiolysis of water, water vapor vaporized by heating, and the like.

[0087] The lower vessel 10 is filled with a gas 32. The gas 32 may be helium, nitrogen, or the like, which functions as a cover gas. Although Fig. 5 shows the vessel 10 with a small amount of liquid 30 introduced therein, the lower vessel 10 is prepared in an empty state, not containing any liquid 30.

[0088] As shown in Fig. 5, the radionuclide production system includes a column 60 for separating and purifying the produced nuclides. The column 60 is provided in a hollow cylindrical shape. The inside of the column 60 is filled with a packing material that functions as a stationary phase for separating and purifying the produced nuclides. The column 60 has connection parts 12 at both ends of the hollow cylindrical body, which are connected to corresponding other connection parts in a closed system to enable the flow of fluid. The connection parts 12 of the column 60 and the connection parts 12 of the containers 10, 20 are provided so as to be connectable to each other in a closed system.

[0089] The stationary phase of the column 60 may be, for example, a resin for extraction chromatography. Specific examples of the stationary phase include N,N,N',N'-tetrakis-2-ethylhexyldiglycolamide, 4,4'(5')-di-tert-butylcyclohexano-18-crown-6, and the like. Since the affinity of the nuclide to the resin depends on the concentration of the acid (such as nitric acid or hydrochloric acid) and the salt concentration, the target radioactive nuclide can be selectively separated and purified.

[0090] A container 10 containing liquid 30 containing redissolved product nuclides is transported to a heating section 40 in a separation and purification process for separating and purifying the product nuclides from the raw material nuclides. A container 10 for collecting waste liquid is placed in a vibration section 50 below the heating section 40. The container 10 containing liquid 30 is placed upside down above the container 10 for collecting waste liquid. The upper container 10 containing liquid 30 is connected to one end of a column 60 via a connection section 12. The other end of the column 60 is connected to a lower container 10 for collecting waste liquid via a connection section 12.

[0091] In the adsorption process, the gas 32 in the container 10 containing the liquid 30 containing the produced nuclides is heated and pressurized by the heating unit 40, and the liquid 30 contained in the container 10 is discharged from the connection unit 12 of the container 10 by the pressure of the gas 32. The gas 32 expands when heated, and pushes the liquid 30 containing the produced nuclides contained in the container 10 toward the container 10 for recovering the waste liquid. A part of small molecules such as helium and nitrogen sealed as a cover gas in the container 10 for recovering the waste liquid permeates the gas permeable material 11 and is released to the outside of the container 10.

[0092] When part of the gas 32 in the lower container 10 is released to the outside of the container 10, the inside of the upper container 10 becomes positive pressure, and the liquid 30 containing the produced nuclides contained in the upper container 10 is introduced into a column 60 packed with a stationary phase. The produced nuclides contained in the liquid 30 are adsorbed by the stationary phase packed in the column 60 while flowing through the column 60. After passing through the column 60, the liquid 30 introduced into the column 60 flows into the lower container 10 and is collected as a waste liquid.

[0093] Large molecules such as radon may remain in the container 10 containing the liquid 30 containing the generated nuclides. Since large molecules such as radon cannot permeate the gas permeable material 11, they are confined in the column 60 and the container 10 for recovering the waste liquid, and are prevented from diffusing into the environment. The liquid 30 that flows into the container 10 for recovering the waste liquid may contain unreacted source nuclide. Therefore, the lower container 10 can be reused for irradiation processing after being removed from the column 60. If a cover gas is sealed in the lower container 10, the liquid 30 containing the unreacted source nuclide that flows in can be covered with the cover gas.

[0094] FIG. 6 is a diagram showing an example of a process for handling containers in a radionuclide production system. Fig. 6 shows a perspective view of the inside of a semi-sealed vessel 10 that undergoes an elution process for eluting the produced nuclides from a stationary phase, which is one of the processes for separating and purifying the produced nuclides from the raw nuclides. As shown in Fig. 6, the semi-sealed vessel 10 can be used for the elution process for eluting the produced nuclides from the stationary phase.

[0095] 6, the upper container 20 contains an eluent 34 prepared to a predetermined concentration and a predetermined amount. The eluent 34 contains a nitric acid solution, a hydrochloric acid solution, water, etc., for eluting the produced nuclides from the stationary phase. The eluent 34 is adjusted to a different concentration from that of the dissolving solution 33 in order to elute the produced nuclides from the stationary phase of the column 60.

[0096] A gas 32 exists above the eluent 34 in the container 20. As the gas 32, helium, nitrogen, or the like that functions as a cover gas is enclosed.

[0097] The lower vessel 10 is filled with a gas 32. The gas 32 may be helium, nitrogen, or the like, which functions as a cover gas. Although Fig. 6 shows the vessel 10 with a small amount of eluent 34 introduced therein, the lower vessel 10 is prepared in an empty state, containing no eluent 34 or liquid 30.

[0098] After the adsorption process in which the produced nuclides are adsorbed onto the stationary phase, one end of the column 60 in which the produced nuclides are adsorbed onto the stationary phase is connected to a container 20 containing an eluent 34 via a connection part 12. The other end of the column 60 is connected to a container 10 for recovering the produced nuclides via a connection part 12. The container 20 containing the eluent 34 is placed in the heating part 40. The container 10 for recovering the produced nuclides is placed below the heating part 40.

[0099] In the elution process, the gas 32 in the container 20 containing the eluent 34 is heated and pressurized by the heating unit 40, and the eluent 34 contained in the container 20 is discharged from the connection part 12 of the container 20 by the pressure of the gas 32. The gas 32 expands when heated, and pushes the eluent 34 contained in the container 20 toward the column 60. A part of small molecules such as helium and nitrogen sealed as a cover gas in the container 10 for recovering the produced nuclides permeates the gas permeable material 11 and is released to the outside of the container 10.

[0100] When a part of the gas 32 in the container 10 is released to the outside of the container 10, the inside of the upper container 20 becomes positive pressure, and the eluent 34 contained in the upper container 20 is introduced into the column 60 filled with a stationary phase. In the process of flowing through the column 60, the eluent 34 elutes the product nuclides adsorbed to the stationary phase packed in the column 60. After flowing through the column 60, the eluent 34 introduced into the column 60 flows into the lower container 10 together with the eluted product nuclides and is collected. If a cover gas is sealed in the lower container 10, the eluent 34 containing the product nuclides that has flowed in can be covered with the cover gas.

[0101] A small amount of large molecules such as radon may remain in the column 60. Since large molecules such as radon cannot permeate the gas permeable material 11, they are trapped in the column 60 or in the container 10 for recovering the generated nuclides, and are prevented from diffusing into the environment. Rn-222 undergoes alpha decay with a half-life of 3.8 days and is gradually converted into a solid radioactive nuclide. Therefore, large molecules such as radon can be treated as a solid by trapping them in the container 10 and leaving them to stand or store them.

[0102] According to the above radionuclide production system and radionuclide production method, the raw material nuclide and the produced nuclide can be handled in the radionuclide production process while being contained in the semi-sealed container. Since the gas-permeable material 11 is used in the semi-sealed container, it is possible to suppress the release of large molecules to the outside of the container while allowing small molecules to be released to the outside of the container. Since the internal pressure of the container is suppressed, the leakage of gaseous radioactive materials is suppressed, and radionuclides can be safely produced.

[0103] According to the above radionuclide production system and method, the increase in the internal pressure of the container can be suppressed to prevent leakage of radioactive materials, so that the parts of the system that perform various processes can be provided with a simpler shielding structure. Since removal equipment such as a filter device that removes radioactive materials in the air and radiation shielding equipment can be provided with a simple structure, the system can be made smaller and less expensive.

[0104] Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible within the scope of the present invention. For example, the present invention is not necessarily limited to having all the configurations of the above embodiment. It is possible to replace a part of the configuration of an embodiment with another configuration, add a part of the configuration of an embodiment to another form, or omit a part of the configuration of an embodiment. [Explanation of symbols]

[0105] 10 containers 11 Gas permeable materials 12 Connection 13 Bremsstrahlung radiation generator 20 containers 30 liquid 31 Solid 32 Gas 33 Lysis solution 34 Eluent 40 Heating section 50 Vibration section 60 Columns

Claims

1. A radionuclide production system for producing a radionuclide by irradiating a liquid or solid containing a raw material nuclide with bremsstrahlung radiation generated by irradiation with an electron beam, comprising: a container for accommodating a liquid or solid containing at least one of the source nuclide and a product nuclide generated from the source nuclide by the irradiation of the bremsstrahlung radiation; The container is a radionuclide production system having a gas permeable material that forms part of a main body of the container and allows gas to pass therethrough depending on the size of the molecule, and a connection portion provided on the main body of the container and connected to a corresponding other connection portion in a closed system to enable the flow of fluid.

2. 2. The radionuclide production system of claim 1, A radionuclide production system, wherein the gas permeable material functions as a molecular sieve that is permeable to molecules smaller than 0.5 nm and impermeable to molecules larger than 0.5 nm.

3. 2. The radionuclide production system of claim 1, A radionuclide production system, wherein the gas permeable material is a material in which zeolite is supported on a porous support.

4. A radionuclide production system according to any one of claims 1 to 3, A heating unit for heating the container is provided, A radionuclide production system, wherein the container is transported to the heating section after a process of irradiating the source nuclide with bremsstrahlung radiation and before a process of separating and purifying the product nuclide from the source nuclide.

5. 5. A radionuclide production system according to claim 4, comprising: The heating unit is a radioactive nuclide production system that heats and dries the liquid containing the produced nuclide contained in the container, or heats and pressurizes the gas in the container, and uses the pressure of the gas to discharge the liquid contained in the container from the connection part.

6. A radionuclide production system according to any one of claims 1 to 3, A vibration unit that vibrates the container, A radionuclide production system, wherein the container is transported to the vibration section after a process of irradiating the source nuclide with bremsstrahlung radiation and before a process of separating and purifying the produced nuclide from the source nuclide.

7. 7. A radionuclide production system according to claim 6, comprising: The vibration unit of the radioactive nuclide production system vibrates the container to agitate the liquid contained in the container.

8. A radionuclide production system according to any one of claims 1 to 3, The container is a radionuclide production system having a bremsstrahlung radiation generator that forms part of a main body of the container and generates the bremsstrahlung radiation when irradiated with the electron beam.

9. A radionuclide production system according to any one of claims 1 to 3, A column for separating and purifying the produced nuclides is provided, The column has connections at both ends thereof that are connected to corresponding other connections in a closed system to allow fluid flow; A radionuclide production system, wherein the column connection and the vessel connection are connectable to each other.

10. 10. A radionuclide production system according to claim 9, comprising: A heating unit for heating the container is provided, A radioactive nuclide production system in which the heating unit heats and pressurizes the gas in one of the containers connected to the column, and causes the liquid contained in the container to be discharged from the connection unit using the gas pressure, and moves the liquid through the column into the other container connected to the column.

11. A radionuclide production system according to any one of claims 1 to 3, A plurality of the containers are provided, A radionuclide production system in which the container connection portion is capable of connecting multiple containers to each other.

12. 12. A radionuclide production system according to claim 11, comprising: A heating unit for heating the container is provided, A radioactive nuclide production system in which the heating unit heats and pressurizes the gas in one of the connected containers, and uses the pressure of the gas to expel the liquid contained in the container from the connection unit and move it into the other container.

13. 12. A radionuclide production system according to claim 11, comprising: A heating unit that heats the container; A vibration unit that vibrates the container, The heating unit heats and pressurizes the gas in one of the containers connected to each other, and discharges the liquid contained in the container from the connection unit by the pressure of the gas and moves the liquid into the other container; The vibration unit of this radioactive nuclide production system vibrates the container into which the liquid has been introduced, thereby dissolving the solid contained in the container.

14. A radionuclide production system according to any one of claims 1 to 3, A radioactive nuclide production system in which the connection part is open to allow fluid to flow when the corresponding other connection part is connected, and closed to prevent fluid from flowing when the corresponding other connection part is not connected.

15. A method for producing a radionuclide by irradiating a liquid or solid containing a raw material nuclide with bremsstrahlung radiation generated by irradiation with an electron beam, comprising the steps of: an irradiation process for irradiating the raw material nuclide with bremsstrahlung radiation; A separation and purification process for separating and purifying product nuclides generated from the source nuclides by the irradiation of the bremsstrahlung radiation, In the irradiation treatment and the separation and purification treatment, a liquid or solid containing at least one of the raw material nuclide and the product nuclide is handled in a state of being contained in a container; The container has a gas permeable material that forms part of a body of the container and allows gas to pass therethrough depending on the size of the molecule, and a connection portion that is provided on the body of the container and is connected to another corresponding connection portion in a closed system to enable the flow of fluid.

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