Fluoride volatility

Roughly, fluoride volatility can be used to remove elements with a valence of 5 or greater: uranium, neptunium, plutonium, metalloids (tellurium, antimony), nonmetals (selenium), halogens (iodine, bromine), and the middle transition metals (niobium, molybdenum, technetium, ruthenium, and possibly rhodium).

This fraction includes the actinides most easily reusable as nuclear fuel in a thermal reactor, and the two long-lived fission products best suited to disposal by transmutation, Tc-99 and I-129, as well as Se-79.

Americium finds use in ionization smoke detectors while californium is used as a spontaneous fission based neutron source.

Fissionable but non-fissile actinoids can be used or disposed of in a subcritical nuclear reactor using an external neutron source such as an Accelerator Driven System.

The lanthanide fluorides are difficult to dissolve in the nitric acid used for aqueous reprocessing methods, such as PUREX, DIAMEX and SANEX, which use solvent extraction.

The Řež nuclear research institute at Řež in the Czech Republic tested screw dosers that fed ground uranium oxide (simulating used fuel pellets) into a fluorinator where the particles were burned in fluorine gas to form uranium hexafluoride.

Blue elements have volatile fluorides or are already volatile; green elements do not but have volatile chlorides; red elements have neither, but the elements themselves are volatile at very high temperatures. Yields at 10 0,1,2,3 years after fission , not considering later neutron capture , fraction of 100% not 200%. Beta decay Kr-85 → Rb , Sr-90 → Zr , Ru-106 → Pd , Sb-125 → Te , Cs-137 → Ba , Ce-144 → Nd , Sm-151 → Eu , Eu-155 → Gd visible.