摘要: Uranium and neptunium in plutonium are determined using an anion exchange x-ray fluorescence method. After a 500-mg plutonium sample is dissolved with 10M HCl and ascorbic acid is added, the solution is passed through an anion-exc... 展开 Uranium and neptunium in plutonium are determined using an anion exchange x-ray fluorescence method. After a 500-mg plutonium sample is dissolved with 10M HCl and ascorbic acid is added, the solution is passed through an anion-exchange column. At least 99.8% of the plutonium passes through the column. The uranium, neptunium, and remaining plutonium, both tetravalent and trivalent, are eluted from the column and evaporated. The small amount of tetravalent plutonium in the eluate solution is reduced to the trivalent state by adding ascorbic acid in 10M HCl to the solution. The resulting solution is pipetted onto a filter paper impregnated with anion-exchange resin. The plutonium, now all in the trivalent state, is washed from the resin paper with 10M HCl, leaving the uranium and neptunium essentially plutonium-free. The L alpha l x-ray lines for the two elements are read and compared with standards prepared in the same way. The recovery of uranium and neptunium is 98% and 91%, respectively. The average relative standard deviation for uranium is 4.6% and for neptunium, 4.1%. 收起