Constant Current Coulometric Determination of Uranium in U₃O₈

Constant current coulometric is established to determine uranium in U₃O₈ in order to correct determination of uranium in uranium product. U(Ⅵ) is reduced to U(Ⅳ) by Fe(Ⅱ) in phosphoric acid. Molybdenum is used as catalyzer, the excess Fe(Ⅱ) is oxidized by nitric acid selectively.The U(Ⅳ) is oxided to U(Ⅵ) by adding chromium(Ⅵ) that is slightly more than uranium’s chemical equivalent in sample solution.The excess chromium(Ⅵ) is titrated by Fe(Ⅱ) which is produced through constant current. The precision is better than 0.015% for 250mg U₃O₈.