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A scheme for producing the α-emitters 212Pb and 212Bi, to be used in a promising method of diagnostics and therapy in oncology – radioimmunotherapy, is proposed. The technology is based on two generators operating in tandem: 228Th/212Pb and 212Pb/212Bi. The first one is based on separation from an initial solution containing thorium isotopes and gaseous 220Rn, which secures the purity of the desired products 212Pb and 212Bi. For a 228Th/212Pb model generator, the efficiency of 220Rn extraction from solution was ~60%. After conditioning, the 212Pb solution from the 228Th/212Pb generator was used to charge a column, which functioned as a 212Pb/212Bi generator, with a cation exchanger.

This technical paper presents information on the basic equipment and more than thirty-year experience of RFNC-VNIIEF activities in the sphere of producing highly enriched isotopes of actinide elements - thorium, uranium, neptunium, plutonium, americium and curium - for scientific research and practical applications. Electromagnetic separator and radiochemical methods are used to produce super pure isotope samples for nuclear-physical radiometric and mass-spectrometric equipment, and also as tracers when analyzing environmental contamination. There are stated science and engineering elaborations of technologies aimed at producing alpha-ray radiating radionuclides - thorium-229, thorium-228, actinium-225, radium-224 - for the purpose of anti-cancer therapy using bismuth-212 and bismuth-213 produced by specially developed generators.

The paper describes the production of highly enriched isotopes of uranium, plutonium and curium by means of electromagnetic separation for scientific and applied research in physics, chemistry, geology and other field. The equipment and radiochemical methods used allows to provide the isotopic pure samples in quantities sufficient to set up nuclear physics experiments, to produce reference materials and standard sources for calibration of radiometrical and mass spectrometrical equipment and for use in radionuclear metrology. Methods of fabrication of special sources or targets and layers of highly enriched isotopes on various substrated are presented. The brief information on developing stable isotope production program is also presented.

We have studied the dependence of the production cross sections of the isotopes {sup 282,283}112 and {sup 286,287}114 on the excitation energy of the compound nuclei {sup 286}112 and {sup 290}114. The maximum cross section values of the xn-evaporation channels for the reaction {sup 238}U({sup 48}Ca,xn){sup 286-x}112 were measured to be {sigma}{sub 3n}=2.5{sub -1.1}{sup +1.8} pb and {sigma}{sub 4n}=0.6{sub -0.5}{sup +1.6} pb; for the reaction {sup 242}Pu({sup 48}Ca,xn){sup 290-x}114: {sigma}{sub 2n}{approx}0.5 pb, {sigma}{sub 3n}=3.6{sub -1.7}{sup +3.4} pb, and {sigma}{sub 4n}=4.5{sub -1.9}{sup +3.6} pb. In the reaction {sup 233}U({sup 48}Ca,2-4n){sup 277-279}112 at E*=34.9=2.2 MeV we measured an upper cross section limit of {sigma}{sub xn}{