Determination of Uranium and Molybdenum in Separation Process of Uranium and Molybdenum (II):Determination of Molybdenum

Determination methods of Molybdenum in various sample in separation process have been developed.The moluranite and leaching residue are dissolved with mixed acid.In nitric acid medium,the molybdenum(Ⅵ)is reduced to molybdenum(Ⅴ) with stannoces dihydrate,and Mo(Ⅴ) combines with ammonium thiocyanate to orange red complex which can be determined by spectrophotometry. The molybdenum in leaching solution,absorbed or eluted solution and stripping solution can be directly determined by spectrophotometry.Molybdenum in ion exchange resins can be rapid spectrophotometric determination after being leached with sodium hydroxide solution at heating condition. Trace Mo in uranium product (chemical concentrate) and high U content samples can be spectrophotometric determined in sulfate acid medium by extracted separation with iso penfanol. Mo in molybdenum product can be determined by EDTA volumetry.In sulfate acid solution of pH2.0,Mo(Ⅵ)is reduced to Mo(Ⅴ) by hydroxylammonium chloride.Mo(Ⅴ)with EDTA forms 1∶1 complex.The excess EDTA can be trititrated by bismuth nitrate. The principle,optimum conditions,operation steps,applied range are introduced.The methods are simple and rapid,and can be used to determine Mo in separation process of uranium and molybdenum.The precision of analysis is less than 5%,and percent recovery is 98.5%～104%.