High Enrichment of 6Li in Molten Nitrates by the Klemm Method

The Klemm method of isotopic enrichment (countercurrent electromigration of molten salts) and many of its implications are reviewed and discussed. On the basis of this principle, a small amount of 6Li was enriched in some experiments from its original abundance, 7:6%, to 94:9% at about 300 °C. The variation of the conditions led to a modified setup where, by disposing a small amount of NaNO3 between the catholyte (NH4NO3) and the zone of LiNO3, the frontal part, where 6Li is to be enriched, could be kept stable under high current density for more than one month without any problem of corrosion. The reasons and implications of this new step are discussed, underlining the up-to-dateness of Klemm’s experiment.