Enrichment of 7Li by countercurrent electromigration of molten LiNO3

A countercurrent electromigration cell using molten LiNO3 and NH4 NO3, which had been devised originally for enrichment of 6Li, was employed for high enrichment of 7Li. By use of a renewable tube at the anode part, impurities gradually accumulated there could be removed along with the product of enriched 7Li, which has solved not only the trouble of high resistance due to impurities in a long run but also the problem of taking out the product. At the anode compartment 7Li was enriched from 92.70% to 99.986% in ca. one month. On the basis of the derived data the electric power needed for enriching 7Li with this method was evaluated. (author)