Patent Number: 
Section: claims

1. A method of producing radionuclides, which includesin an irradiation zone, irradiating a target medium comprising at least a target nuclide material, with neutron irradiation, thereby causing radionuclides to form in the target nuclide material, with at least some of the formed radionuclides being ejected from the target nuclide material;capturing and collecting the ejected radionuclides in a recoil capture material which is selected from amorphous carbon, carbon allotropes and mixtures thereof, the amorphous carbon and/or carbon allotropes not having an empty cage structure at crystallographic level, with the ejected radionuclides thereby being concentrated or enriched in the recoil capture material relative to cold nuclei; andrecovering the captured radionuclides from the recoil capture material. 2. The method according to claim 1, wherein the target nuclide material is selected from the group consisting of a pure metal and a metal compound. 3. The method according to claim 2, wherein the metal of the target nuclide material is selected from the group of metal elements in the Periodic Table of Elements extending from scandium, of atomic number 21, to bismuth, of atomic number 83, both elements included, with the non-metal elements arsenic, selenium, bromine, krypton, tellurium, iodine and xenon thus being excluded, 4. The method according to claim 3, wherein the metal of the target nuclide material is tin. 5. The method according to claim 1, wherein the target nuclide material and the recoil capture material are both in finely divided particulate form, each having a mean particle size of at most about 50 nm. 6. The method according to claim 5, which includes mixing the target nuclide material and the recoil capture material, with the target medium thus comprising both target nuclide material and recoil capture material. 7. The method according to claim 1, wherein irradiating the target medium includes placing the target medium in the path of a neutron flux from a neutron source. 8. The method according to claim 1, in which recovering the captured radionuclides from the recoil capture material includes treating the recoil capture material with a dilute and/or a concentrated acidic extraction solvent, thereby to form a recoil capture material suspension, and chemically extracting or leaching captured radionuclides from the recoil capture material, to obtain a radionuclide-enriched extraction solvent. 9. The method according to claim 8, which includes incubating the recoil capture material suspension for a period which does not exceed the half-life of the captured radionuclides. 10. The method according to claim 8, which includes recovering or separating radionuclide-enriched extraction solvent from the recoil capture material by means of centrifugation, vortex separation and/or filtration. 11. The method according to claim 1, which includes recovering the captured radionuclides from the recoil capture material by treating the recoil capture material with an alkaline extraction solvent. 12. The method according to claim 1, which includes recovering the captured radionuclides from the recoil capture material by combusting the recoil capture material in oxygen. 13. The method according to claim 8, in which the target medium comprises a mixture of the recoil capture material and the target nuclide material and the method includes separating the recoil capture material from the target nuclide material before recovering radionuclides from the recoil capture material. 14. The method according to claim 13, wherein separating the recoil capture material from the target nuclide material is achieved by means of liquid-liquid extraction, using an aqueous liquid and an organic liquid as liquid-liquid extraction solvents.