U_3O_8样品用HNO_3溶解,用TBP-CCl_4溶液萃取以分离铀,水相用HClO_4蒸干,残渣溶于0.05mol/l的HClO_4和0.03mol/l的酒石酸混合底液中,用方波阳极伏安法测定铅,峰电位为-0.376 V,然后加入氨水使溶液pH约为9.5,用方波阴极伏安法测定铁,峰电位为-1.426V。方法的准确度和精密度都较好。 U_3O_8 samples were dissolved with HNO_3, extracted with TBP-CCl_4 solution to separate uranium, the aqueous phase was evaporated to dryness with HClO_4, the residue was dissolved in 0.05mol / l HClO_4 and 0.03mol / l tartaric acid mixed bottom solution, with a square wave anodic voltammetry Method, the peak potential was -0.376 V, and then ammonia solution was added to make the solution pH about 9.5. The square wave cathodic voltammetry was used to determine the peak potential of iron at -1.426V. Method accuracy and precision are better.