Device for isotope separation by ion cyclotron resonance

• US 5,422,481 A
• Filed: 05/13/1994
• Issued: 06/06/1995
• Est. Priority Date: 05/26/1993
• Status: Expired due to Fees

• Current Assignee: Compagnie Generale DES Etablissements Michelin SCA
• Original Assignee: Compagnie Generale DES Etablissements Michelin SCA
• Inventors: Louvet, Pierre
• Primary Examiner(s): Berman, Jack I.
• Application Number:
  US08/242,136
• Time in Patent Office: 389 Days
• Field of Search: 250/291, 250/290, 250/283, 250/282
• US Class Current: 250/291
• CPC Class Codes: B01D 59/02 Separation by phase transition

Abstract

Device for isotope separation by ion cyclotron resonance (ICR). This device comprises a vertical enclosure (2), means (6) for producing a homogeneous, vertical magnetic field in said enclosure, a plasma source (8) for producing in the central part of the enclosure an ion plasma of the isotope to be separated, means (10) for producing in the enclosure an electric field perpendicular to the magnetic field and oscillating at the ion cyclotron frequency of the isotope to be separated, which is adjusted as a function of the mass of said isotope, collection means (12) for recovering a mixture which is enriched and a mixture which is depleted with said isotope. The plasma source comprises a container (14) containing the element (20), whose isotope is to be separated and means (18) for ionizing atoms of the element. Application to the separation of the isotopes of gadolinium.

Claims

1. Device for isotope separation by ion cyclotron resonance, said device comprising:

a tight enclosure (2) having an elongated shape in one direction,

means (4) for forming a vacuum in said enclosure,

means (6) for producing a homogeneous magnetic field in the central part of the enclosure and parallel to said direction,

a plasma source (8) for producing in the enclosure a plasma containing ions of the isotope to be separated,

means (10) for producing in the central part of the enclosure an electric field perpendicular to the magnetic field and oscillating at a frequency close to the ion cyclotron frequency of the isotope to be separated, which is adjusted as a function of the mass of said isotope to be separated and

collection means (12) for recovering on the one hand a mixture enriched with said isotope and on the other a mixture depleted with said isotope,

characterized in that the enclosure (2) is positioned in a vertical direction and therefore has a so-called lower part and a so-called upper part, the magnetic field then being vertical, in that the collection means (12) are placed in the upper part of the enclosure and in that plasma source (8) is placed in the lower part of the enclosure and comprises;

an electrically conductive container (14) having an opening facing the upper part of the enclosure and which contains the element (20) whose isotope is to be separated, said container being provided so that at least its outer part remains solid during the operation of the device,

means (18) for ionizing atoms of the element and

maintaining means (16), which maintain during said operation part of the content of the container in the vicinity of its bottom at an operating temperature able to bring about the melting of the element or its sublimation, whilst leaving the upper part of the container at a temperature below the melting point of the element.

2. Device according to claim 1, characterized in that the means for producing the magnetic field comprise a magnetic coil (6), which surrounds the enclosure (2) and in that the container (14) is shaped like a cylinder of revolution around the axis (X) of the coil (6).

3. Device according to claim 1, characterized in that the container (14) is made from an electrically conductive, amagnetic material, whose melting point is above the operating temperature.

4. Device according to claim 1, characterized in that the element whose isotope is to be separated is a metal and in that the container (14) is made from said metal or an alloy of said metal and has an adequate thickness so that its outer part remains at a temperature below the melting point of the element or alloy during the operation of the device.

5. Device according to claim 1, characterized in that the maintaining means are heat shields (16) made from amagnetic materials and which surround the container (14), except in the upper part thereof.

6. Device according to claim 1, characterized in that it also comprises means (22) for heating the container (14).

7. Device according to claim 1, characterized in that it also comprises means (24) for heating the bottom of the container (14).

8. Device according to claim 1, characterized in that it also comprises means (26) for the negative polarization of the container (14).

9. Application of the device according to claim 1 to the isotope separation of a metal, the container containing said metal or an alloy of said metal, whose saturated vapour pressure is between 10^-3 and 10 Pa at a temperature slightly above the melting point of the metal or alloy.

10. Application of the device according to claim 1 to the isotope separation of a metal, which sublimates with a saturated vapour pressure between 10^-3 and 10 Pa and at a temperature below 1500°

C.