Determination of Hydrogen Fluoride and Uranium(VI) in Crude Uranium Hexafluoride by Hydrolysis and Potentiometric Titration

摘要

A simple method for determining HF and U(VI) in a hydrolyzed solution of UF6 by alkalimetry is described.About 1g of UF6 was taken in a polytrifluoromonochloroethylene tube, and hydrolyzed with about 50ml of water in a closed polyethylene bottle. Using a glass electrode, HF in the hydrolyzed solution was titrated potentiometrically with an alkali solution, after the U(VI) had been masked with ammonium sulfate. When the equivalence point for the free acid was reached, hydrogen peroxide was added to the solution and the liberated acid equivalent to U(VI) was titrated with the same standard alkali solution.Assuming that the hydrolysis of UF6 takes place stoichiometrically, the accuracy of this method was roughly evaluated to be ±10% for the ratio of HF/UF6 and ±1% for the value of U(VI) in the range of 0 to 1 mole of HF per mole of UF6.