KR-20260063451-A - COMPOSITIONS FOR REMOVING RADIONUCLIDES THAT FACILITATE RADIONUCLIDE REMOVAL AT LOW TEMPERATURES AND METHODS FOR REMOVING RADIONUCLIDES

Abstract

The present invention relates to a composition for removing radionuclides and a method for removing radionuclides that facilitates the removal of radionuclides at low temperatures. More specifically, the invention relates to a composition for removing radionuclides and a method for removing radionuclides that facilitates the removal of radionuclides at low temperatures, which allows for the removal of radionuclides even at low temperatures, making it easy to work outdoors even on days with low temperatures, thus offering excellent utility, and also to a method that is recyclable, which can drastically reduce the amount of radioactive waste, making it environmentally friendly, and also allows for the removal of radionuclides within a short period of time compared to conventional methods, thus offering superior efficiency, and also has a very high removal rate of radionuclides, particularly on porous surfaces.

Inventors

• 양희만
• 김형주
• 김성욱
• 박찬우
• 정예원
• 이가은

Assignees

• 한국원자력연구원

Dates

Publication Date

20260507

Application Date

20241030

Claims (19)

1. A first solution containing a polymer comprising hydroxyl groups and functional groups and a first solvent; and A composition for removing radionuclides that facilitates the removal of radionuclides at low temperatures, comprising: a second solution comprising a compound containing a boronic acid group and a second solvent.
2. In paragraph 1, A composition for removing radionuclides that facilitates the removal of radionuclides at low temperatures, characterized in that the functional group of the above polymer has higher hydrophobicity compared to the hydroxyl group.
3. In paragraph 1, A composition for removing radionuclides that facilitates the removal of radionuclides at low temperatures, characterized in that the above-mentioned functional groups comprise one or more selected from the group consisting of acetoxy groups (OAc), carboxyl groups ( COOH ), and amine groups (NH₂).
4. In paragraph 1, A composition for removing radionuclides that facilitates the removal of radionuclides at low temperatures, characterized in that the above polymer comprises one or more selected from the group consisting of PVA, alginate, gum arabic, cellulose derivatives, guar gum, locust bean gum, polyethylene glycol, polyglycerol, polyvinylpyrrolidone, poly(N-isopropylacrylamide), and poly(glucose derivatives) to which functional groups have been introduced.
5. In paragraph 1, A composition for removing radionuclides that facilitates the removal of radionuclides at low temperatures, characterized in that the weight-average molecular weight of the above polymer is 1,000 to 200,000 g/mol.
6. In paragraph 1, A composition for removing radionuclides that facilitates the removal of radionuclides at low temperatures, characterized in that the compound containing the above-mentioned boronic acid group is not a polymer.
7. In paragraph 1, A composition for removing radionuclides that facilitates the removal of radionuclides at low temperatures, characterized in that the compound containing the above-mentioned boronic acid group comprises one or more selected from the group consisting of borax, boric acid, phenylboronic acid, methylboronic acid, and pyridylboronic acid.
8. In paragraph 1, A composition for removing radionuclides that facilitates the removal of radionuclides at low temperatures, characterized in that the first solvent and the second solvent are each a mixture of water and a lower alcohol having 1 to 10 carbon atoms.
9. In paragraph 8, A composition for removing radionuclides that facilitates the removal of radionuclides at low temperatures, characterized in that each of the first solvent and the second solvent has a weight ratio of water to lower alcohol of 99:1 to 50:50.
10. In paragraph 1, The above-mentioned first liquid contains the polymer in an amount of 1 to 40 weight%, and A composition for removing radionuclides that facilitates the removal of radionuclides at low temperatures, characterized by containing 0.1 to 20 weight% of a compound containing a boronic acid group in the second solution above.
11. In paragraph 1, A composition for removing radionuclides that facilitates the removal of radionuclides at low temperatures, characterized in that at least one of the first and second solutions comprises at least one of an adsorbent for removing radionuclides and an ion exchange salt.
12. In paragraph 1, A composition for removing radionuclides that facilitates the removal of radionuclides at low temperatures, characterized in that the first and second solutions each exist in a liquid state within a temperature range of -6°C to 50°C.
13. In paragraph 1, A composition for removing radionuclides that facilitates the removal of radionuclides at low temperatures, characterized in that when the first solution and the second solution are mixed, the polymer and the compound containing the boronic acid group cross-link to form a hydrogel.
14. In Paragraph 13, A composition for removing radionuclides that facilitates the removal of radionuclides at low temperatures, characterized in that the above hydrogel has a storage modulus of 2,000 to 7,000 Pa and a loss modulus of 2,000 to 30,000 Pa at 0°C.
15. (a) A step of preparing a first solution comprising a polymer containing hydroxyl groups and functional groups and a first solvent; (b) a step of preparing a second liquid comprising a compound containing a boronic acid group and a second solvent; and (c) a step of spraying or applying the first solution and the second solution, respectively, onto a surface contaminated by a radionuclide, and then cross-linking the polymer and the compound to form a hydrogel on which the radionuclide is adsorbed; comprising a method for removing radionuclides.
16. In paragraph 15, A method for removing radionuclides characterized in that the above hydrogel has a storage modulus of 2,000 to 7,000 Pa and a loss modulus of 2,000 to 30,000 Pa at 0°C.
17. In paragraph 15, A method for removing radionuclides characterized in that at least one of the first solution and the second solution comprises at least one of an adsorbent for removing radionuclides and an ion exchange salt.
18. In paragraph 15, A method for removing radionuclides, wherein the cross-linking in step (c) above is achieved through a dehydration condensation reaction between the polymer and the compound.
19. In paragraph 15, (d) a step of immersing the hydrogel on which the radioactive nuclide is adsorbed in water, and then selectively dissolving only the hydrogel; further comprising a method for removing a radioactive nuclide.

Description

Compositions for removing radionuclides that facilitate removal of radionuclides at low temperatures and methods for removing radionuclides The present invention relates to a composition for removing radionuclides and a method for removing radionuclides that facilitates the removal of radionuclides at low temperatures. More specifically, the invention relates to a composition for removing radionuclides and a method for removing radionuclides that facilitates the removal of radionuclides at low temperatures, which allows for the removal of radionuclides even at low temperatures, making it easy to work outdoors even on days with low temperatures, thus offering excellent utility, and also to a method that is recyclable, which can drastically reduce the amount of radioactive waste, making it environmentally friendly, and also allows for the removal of radionuclides within a short period of time compared to conventional methods, thus offering superior efficiency, and also has a very high removal rate of radionuclides, particularly on porous surfaces. Radioactive nuclides are used not only in the nuclear field but also in various research and industrial settings. Consequently, surfaces such as concrete, cement, paint, and metals in facilities handling radioactive nuclides, particularly nuclear facilities, are inevitably contaminated with these nuclides. Furthermore, in the event of radioactive leakage accidents like the Chernobyl and Fukushima nuclear disasters, large quantities of radioactive nuclides are released into the environment, contaminating the surfaces of numerous facilities, such as various buildings and roads in residential areas. Since these radioactively contaminated surfaces can cause continuous exposure to living organisms, including humans, their removal is required. Accordingly, active research is being conducted to develop technologies for the economical and effective removal of radioactive nuclides present on various contaminated surfaces. Among these, surface decontamination methods using high-pressure water have been widely applied; however, there is a problem with low decontamination efficiency for radioactive contaminated surfaces and strongly adsorbed, fixed contaminants. Post-use wash water is contaminated with radionuclides, generating a large volume of contaminated water; if this water flows into the sewer system, radioactive contaminants can directly contaminate urban infrastructure. Therefore, to improve the low removal efficiency of water-based washing methods, ion washing methods utilizing ion exchange with radionuclides present on contaminated surfaces have been attempted; however, the problem of generating large amounts of contaminated water still persists. Meanwhile, among surface decontamination methods, a method using a peel-off coating agent has been reported as a method that does not generate a large amount of contaminated water after use. Although this method has demonstrated superior radionuclide removal efficiency compared to physical decontamination methods such as high-pressure water, it also has the following disadvantages. First, the solvent and chelator, which are components of the coating material itself, are substances harmful to the human body. Additionally, since the coating agent must have relatively weak adhesion to be easily peeled off from the contaminated surface, there are limitations in removing adhesive contamination that is strongly attached to the surface. Second, there is a disadvantage in that a large amount of radioactive waste is generated because the coating material used for radionuclide removal becomes radioactive waste itself. Third, currently commercialized peel-off coating agents require a curing time of several hours. Furthermore, they have been used to remove radioactive contamination on non-porous surfaces such as metal and aluminum, and their decontamination effect against radionuclides chemically bonded to the surface of porous building materials such as concrete is low. To solve these problems, a method for removing radionuclides using a PVA-borate complex-based hydrogel coating agent (Patent Registration Publication No. 10-2075339) has been reported in the past. However, since the coating agent uses water as a solvent, it is difficult to spray for coating at low temperatures, especially in environments below 0°C, and the formed hydrogel also condenses, making it difficult to remove radionuclides. Therefore, there is a need to develop a composition for removing radionuclides that facilitates easy spraying by preventing the spray liquid from condensing even under low-temperature conditions, enables high-efficiency removal of radionuclides by preventing the coating agent from condensing, is environmentally friendly by generating minimal waste during the removal process, and allows for high-efficiency removal of radionuclides without the use of harmful additives. FIG. 1 is a diagram showing the process of a method for removing radionuclide