An electromagnetic apparatus with a high resolving power for the separation of the isotopes of the heavy elements

The operating principles and the main features of an electromagnetic apparatus which has been designed and constructed for the separation of isotopes with a relative mass difference of about 1/240 are here described.An axially-symmetric magnetic field is used (focussing angle 225 °) in which the dispersion is proportional to the square of the focussing angle. The dispersion obtained with the separation apparatus is 20 mm for a 1% relative difference in mass. The magnetic field of the apparatus is stabilized to within 0.005% with the help of a circuit containing electron-beam regulators. Ion sources, with a discharge in the vapor of the working and auxiliary substances, were developed for the separation of large and small quantities of the raw material. General-purpose ion collectors were also developed.Some results of the separation of lead, uranium and plutonium isotopes are given. The enrichment factor in the separation of lead isotopes reaches 300, while for uranium and plutonium it is 1000.We express our gratitude to the personnel of the laboratory who took part in the work and also to G. N. Iakovlev and his collaborators for the preparation of the working substances and for the extraction of the separated isotopes.     

Plasma centrifuge for separation of metal elements and isotopes

Centrifugal separation of elements has been explored in rapidly rotating metal plasmas. The plasma is produced and driven into rotation by cross-field, vacuum discharge in a coaxial plasma gun. A large separation factor is measured in Cu/Zn plasmas. In particular, a hollow density profile which improves the separative power is found to be established in the plasma column.     

The design of beam lines with high resolving power

A systematic method of designing beam lines, which reduces the energy spread and emittance of particle beams from accelerators to match target requirements is discussed.     

PILIS: post-ISOCELE laser isobar separation; a high efficiency apparatus for laser spectroscopy

A new experimental setup PILIS II has been installed on-line with the ISOCELE isotope separator (IPN, Orsay). The mass-separated ions are slowed from 30 kV to 500 V and implanted on a graphite collecting disk. The atoms are then thermally desorbed at the implantation region by Nd: YAG laser pulses and selectively ionized by three laser beams. The ions created are mass identified by a time-of-flight (TOF) system. Two versions of the TOF system with accelerating voltages of 1.5 and 30 kV were used to carry out hyperfine structure measurements. With the 30 kV system we obtained an overall detection efficiency of 1.4 × 10⁻⁵. First measurements were performed on very light gold and platinum isotopes. It has been shown that PILIS II is well adapted to study very short half-life isotopes ( ).     

气相热色谱法在线分离重离子核反应中的铪和钽同位素

为探索气体喷嘴传输和热色谱法在线分离短寿命的超锕系元素的分离条件,用72.5MeV的~(12)C离子轰击~(163)Dy和~(165)Ho混合靶产生的铪、钽同位素,进行了在线分离研究。 以前的研究表明,103号元素已是锕系的结尾,104号和105号元素分别为类铪和类钽元素,它们的化学性质对应相似。据此,我们用~(163)Dy(~(12)C,xn)Hf、~(165)Ho(~(12)C,xn)Ta两个反     

Separation of germanium and magnesium isotopes in a small electromagnetic separator

A method is described for the electromagnetic separation of germanium and magnesium isotopes in a small electromagnetic separator with a focusing angle of 180 °. The construction of an ion source and an ion collecter (isotope receiver) is considered. The ion source, which maintains a discharge in the vapor of the element to be separated, operates satisfactorily in a temperature range up to 1500 °C. The construction of the receiver permits the simultaneous collection of all the isotopes of the element to be separated. The relation of the size of the ion current, focused on the receiver, to the method of discharge in the source was investigated. During the separation of germanium isotopes the ionic current at the receiver reached 15–20 ma; during magnesium separation it was 35–40 ma. Every hour ～ 40 mg of enriched germarilum isotopes (or ～ 25 mg of enriched magnesium isotopes) was collected in the receiver's containers. The coefficient of material recovery was 2–6%. Mass-spectrometric analyses were carried out on metal samples for the enriched germanium isotopes and the compound Mgl₂ for the magnesfurn isotopes. The enrichment coefficient for germanium and magnesium lay within the limits 17–175 depending on natural diffusion and mass of the isotopes.     

Separation of germanium and magnesium isotopes in a small electromagnetic separator

A method is described for the electromagnetic separation of germanium and magnesium isotopes in a small electromagnetic separator with a focusing angle of 180 °. The construction of an ion source and an ion collecter (isotope receiver) is considered. The ion source, which maintains a discharge in the vapor of the element to be separated, operates satisfactorily in a temperature range up to 1500 °C. The construction of the receiver permits the simultaneous collection of all the isotopes of the element to be separated. The relation of the size of the ion current, focused on the receiver, to the method of discharge in the source was investigated. During the separation of germanium isotopes the ionic current at the receiver reached 15–20 ma; during magnesium separation it was 35–40 ma. Every hour 40 mg of enriched germarilum isotopes (or 25 mg of enriched magnesium isotopes) was collected in the receiver's containers. The coefficient of material recovery was 2–6%. Mass-spectrometric analyses were carried out on metal samples for the enriched germanium isotopes and the compound Mgl₂ for the magnesfurn isotopes. The enrichment coefficient for germanium and magnesium lay within the limits 17–175 depending on natural diffusion and mass of the isotopes.     

Method for fast separation of iodine isotopes on silver-containing membranes

A method for fast separation of iodine isotopes from the water coolant of a nuclear power facility, making possible maximal simplification of sample preparation, reducing it to filtering a sample acidified with ascorbic acid to pH = 3 through a silver-impregnated acetylcellulose membrane, has been developed for monitoring fuel-element seal tightness. Impurity ⁹⁹Mo, ¹⁸⁷W, ⁵¹Cr, and ²³⁹Np do not separate onto the membrane. The materials and reagents used are nontoxic, explosion-proof, and fire-proof. The time for analysis is reduced by a factor of 10. A point source makes it possible to increase the radiation detection efficiency, decrease the measurement time, and decrease the limit of detection by more than a factor of 10. __________ Translated from Atomnaya énergiya, Vol. 104, No. 4, pp. 238–241, April, 2008.     

Prospects for using chemical isotopic exchange for separation of hydrogen isotopes

The status of the production of heavy water in the world and Russia is analyzed. It is shown by comparing the main methods of producing heavy water that the most promising method for reprocessing untreated heavy-water wastes, including the removal of tritium from them, is isotopic exchange between water and hydrogen. The basic parameters of a pilot commercial setup, which makes it possible to obtain heavy water with a deuterium atomic fraction of 99.8%, are presented. The problem of removal of tritium from heavy-water wastes using the water-hydrogen system at the starting stage and hydrogen-palladium hydride at the final stage, is examined. The combination of methods developed makes it possible to produce a universal module for removing protium and tritium from heavy-water wastes. 1 figure, 2 tables, 20 references. D. I. Mendeleev Russian Chemical Engineering University. Translated from Atomnaya énergiya, Vol. 86, No. 3, pp. 198–203, March, 1999.     

A linear mass spectrometer by induced Hall potential for electromagnetic isotopic separation working at high pressures

In this paper a novel alternative for bulk electromagnetic separation working at high pressures is proposed. It is shown that if a self-induced Hall potential is stimulated in the boundaries, the system will be able to take advantage of the collisions process, boosting the isotopic separation and resulting in a linear-spectrometer with a higher spatial separation per unit length than a traditional calutron. Although originally the concept was devised for the production of medical isotopes where the minority isotope to be separated is produced by neutron capture and is the heavier isotope, if the Hall potential is replaced by an external electrical field, the concept is equally applicable for situations where the minority isotope is the lighter one, as for example in the enrichment of uranium. Additional R&D is required to explore further the possibilities of this concept and to identify optimal values for several of the system design variables.