# US 2013/0211172 A1 · Method for partially decontaminating radioactive waste > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0211172 A1 - Document ID: US20130211172A1 - Status: Published application - Kind: A1 - Application number: 13/808,214 - Filed: 2011-07-06 - Published: 2013-08-15 - Earliest claimed: 2010-07-12 - Assignees: Forschungszentrum Juelich GmbH - Inventors: Werner F. Lensa; Dirk Vulpius; Hans-Juergen Steinmetz; Kathrin Baginski; Rahim Nabbi - Web page: https://patentgrep.com/patent/US20130211172A1 ## CPC - G21F 9/30: Processing (separating different isotopes of the same chemical element B01D59/00) - G21F 9/002: {Decontamination of the surface of objects with chemical or electrochemical processes} - G21F 9/302: {in an inorganic matrix} - G21F 9/305: {Glass or glass like matrix (C03B5/005 takes precedence; compositional aspects C03C)} - G21F: PROTECTION AGAINST X-RADIATION, GAMMA RADIATION, CORPUSCULAR RADIATION OR PARTICLE BOMBARDMENT; TREATING RADIOACTIVELY CONTAMINATED MATERIAL; DECONTAMINATION ARRANGEMENTS THEREFOR (radiation protection by pharmaceutical means A61K8/00, A61Q17/04; in cosmonautic vehicles B64G1/54; combined with a reactor G21C11/00; combined with X-ray tubes H01J35/16; combined with X-ray apparatus H05G1/02) ## Abstract Methods for partially decontaminating radioactive waste wherein the waste is first mixed, or brought in contact, with at least one corrosive medium. Activation energy is then supplied to the corrosive medium, so that at least a portion of the radionuclide present in the waste is converted into at least one gaseous reaction product, or is dissolved, by hydrogen or hydrogen ions, oxygen or oxygen ions, and/or halogen (for example chlorine) or halogen ions from the corrosive medium. The aim is that of decontaminating a 12C/13C-containing porous solid waste, which is contaminated with the 14C radionuclide. For this purpose, CO2 and/or hydrogen are applied as corrosive media to the waste, so that at least a portion of the waste is reacted to form at least one gaseous reaction product, wherein the process temperature is selected so that the 14C radionuclide is enriched in the reaction product over 12C/13C. ## Claims ### Claim 1 A method for at least partially decontaminating solid waste that is contaminated with at least one radionuclide, wherein waste having a matrix made of non-radioactive base material is selected, in which the radionuclide is embedded, wherein: a) the waste is mixed, or brought in contact, with at least one corrosive medium, which is inert with respect to the base material before the activation energy is supplied, wherein at least one binary metal oxide, sulfate, nitrate, hyroxide, carbonate, hydride, halogen succinimide and/or a peroxide, an acid, a lye, a completing agent and/or an electrolyte, and/or another reagent that can be pyrolyzed and/or dehydrated is selected as the corrosive medium and then b) activation energy is supplied to the corrosive medium, so that hydrogen or hydrogen ions, oxygen or oxygen ions, and/or halogen or halogen ions, and/or nitrate and/or sulfate ions, and/or carbon dioxide, and/or water vapor are formed from the corrosive medium, and as a result of these products thus formed: c) at least a portion of the radionuclide present in the waste is converted into at least one gaseous reaction product or is dissolved. ### Claim 2 (depends on 1) The method according to claim 1, wherein the hydrogen, hydrogen ions, oxygen, oxygen ions, halogen, and/or halogen ions react in the nascent state with the radionuclide. ### Claim at position 3 3-5. (canceled) ### Claim 6 (depends on 1) A method according to claim 1, wherein at least one radionuclide, with which the waste is contaminated, was formed by a nuclear reaction, and more particularly nuclear fission or neutron activation. ### Claim 7 (depends on 6) The method according to claim 6, wherein the nuclear reaction took place in the material of the waste. ### Claim 8 (depends on 1) A method according to claim 1, wherein waste is selected that contains a further isotope of the same element, in addition to the radionuclide. ### Claim 9 (depends on 1) A method according to claim 1, wherein porous waste is selected. ### Claim 10 (canceled) ### Claim 11 (depends on 1) A method according to claim 1, wherein waste containing 12C and/or 13C is selected. ### Claim 12 (depends on 1) A method according to claim 1, wherein waste that is present in the form of solid pieces, granules or powder is selected. ### Claim at position 11 13-14. (canceled) ### Claim 15 (depends on 1) A method according to claim 1, wherein a liquid corrosive medium is selected. ### Claim 16 (canceled) ### Claim 17 (depends on 1) A method according to claim 1, wherein the activation energy is supplied in form of heat, UV rays, or gamma rays. ### Claim 18 (depends on 17) The method according to claim 17, wherein the heat is supplied by heating, irradiating with microwaves, or by an alternating magnetic field. ### Claim 19 (depends on 1) A method according to claim 1, wherein a temperature between 100 and 1100° C., preferably between 200 and 750° C., and still more preferably between 200 and 500° C., is selected. ### Claim 20 (depends on 1) A method according to claim 1, wherein the activation energy is supplied by applying a direct current or by an alternating magnetic field. ### Claim 21 A method for decontaminating a 12C/13C-containing porous solid waste, which is contaminated with the 14C radionuclide, wherein CO2 is applied as corrosive medium to the waste, so that at least a portion of the waste is reacted to form at least one gaseous reaction product, wherein the process temperature is selected so that the radionuclide is enriched in the reaction product over 12C/13C. ### Claim 22 (depends on 21) The method according to claim 21, wherein CO2 is separated from the reaction product by freezing out or by washing out with a lye. ### Claim 23 (depends on 21) The method according to claim 21, comprising carrying out the method in a rotating reaction vessel, in a mixer, or in a fluidized bed reactor. ### Claim 24 (depends on 1) A method according to claim 1, wherein additionally at least one further reactive medium is applied to the waste. ### Claim 25 (depends on 1) A method according to claim 1, wherein the reaction of carbon is stopped when the ratio of the reaction rates of 14C to 12C/13C passes a predetermined threshold value. ### Claim 26 (depends on 1) A method according to claim 1, wherein graphite, reactor graphite, or carbon brick is selected as the waste. ### Claim 27 (depends on 26) The method according to claim 26, wherein atoms, molecules, or ions are intercalated between the crystal lattice planes of the graphite. ### Claim 28 (depends on 1) A method according to claim 1, wherein waste having a porosity of at least 5%, and preferably between 10 and 25%, is selected. ### Claim 29 (depends on 1) A method according to claim 1, wherein 14C and/or a metallic radionuclide is converted into at least one gaseous reaction product or is dissolved, ### Claim 30 (depends on 1) A method according to claim 1, wherein a catalyst is loaded to the inner surfaces of the pore system in the waste, wherein the catalyst lowers the required activation energy for the reaction of the corrosive medium with the radionuclide. ### Claim 31 (depends on 1) A method according to claim 1, wherein the waste is annealed at temperatures above 1000° C., and preferably between 1300 and 1500° C., before the corrosive medium is added. ### Claim 32 (depends on 1) A method according to claim 1, wherein the waste is embedded in a geopolymer after withdrawing the reaction product or products. ### Claim 33 (depends on 1) A method according to claim 1, wherein at least a portion of the waste is reacted with zirconium to form zirconium carbide after withdrawing the reaction product or products. ### Claim 34 (depends on 33) The method according to claim 33, wherein at least a portion of the waste is reacted with zirconium alloy waste.