METHOD FOR ADJUSTING VALENCE OF AMERICIUM IN NITRIC ACID-BASED WATER SOLUTION

摘要

PURPOSE:To easily separate americium from a short half life nuclear fission product by solvent extraction or the like and reduce a management load of high-level waste by controlling the valence of americium. CONSTITUTION:The valence adjustment process comprises a process 2 for preparing nitric acid concentration of high-level liquid waste produced in reprocessing of spent fuel and a valence adjustment process 4 using peroxodisulfate and a silver ion equivalent or more to nitric acid as oxidizing agent. Thereafter, americium is oxidized up to hexavalent and separated from unclear fusssion produced nuclides of trivalent rare earth elements or the like.