Rare earths, neutron capture product

Table IL Neutron Capture Product Enrichment with Rare Earths...

This paper describes a new reaction which may yield useful amounts of the product isotope following neutron capture by lanthanide or actinide elements. The trivalent target ion is exchanged into Linde X or Y zeolite, fixed in the structure by appropriate heat treatment, and irradiated in a nuclear realtor. The (n, y) product isotope, one mass unit heavier than the target, is ejected from its exchange site location by y recoil. It may then be selectively eluted from the zeolite. The reaction has been demonstrated with several rare earths, and with americium and curium. Products typically contain about 50% of the neutron capture isotope, accompanied by about 1% of the target isotope. The effect of experimental variables on enrichment is discussed. 

Pyrochemical reprocessing using molten salts has the potential to recover actinides from spent nuclear fuels [1,2], Since some fission products of rare earth elements have large neutron capture cross-sections, separating them from actinides is desirable. In order to control the separation performance, monitoring the concentration of each element is important. Absorption spectrophotometric analysis is superior to determine the solute concentration and hence its application is examined. 

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