METHOD OF JOINT DETERMINATION OF MASS CONTENT OF URANIUM AND PLUTONIUM IN SOLUTIONS WITH A CULONOMETRIC METHOD WITH CONSTANT POWER OF CURRENT Russian patent published in 2018 - IPC G01N27/42 

FIELD: measurement technology.

SUBSTANCE: use to determine the mass content of uranium and plutonium in solutions by coulometric method. Essence of invention consists in that, at constant current strength aliquot of a solution of mixed uranium-plutonium fuel is evaporated to wet salts, to determine plutonium, a portion of the aliquot is dissolved in 1 mole⋅l^-1 HClO₄, oxidize Pu⁴⁺ up to PuO₂²⁺ silver(II) oxide, put the sample in electrochemical cell, titration of plutonium in inert atmosphere, at constant current strength by electrogenerated Fe²⁺, calculate the content of plutonium in terms of the amount of electricity spent on the electrochemical reduction of Fe³⁺ to Fe²⁺ on the electrode, the second portion of the aliquot of the evaporated solution is dissolved in 2 mols⋅l^-1 H₂SO₄, restore uranium and plutonium to U⁴⁺ and Pu³⁺ amalgam of zinc, oxidize uranium and plutonium to UO₂²⁺ and Pu⁴⁺ respectively, adding potassium dichromate in excess, the solution is placed in an electrochemical cell with the same solution of the background electrolyte as in the determination of plutonium, titration of excess potassium dichromate with electrogenerated Fe²⁺ ions, knowing the total amount of potassium dichromate added to the working solution and the mass of its excess determined in the second titration, calculate its mass spent on oxidation of U⁴⁺ and Pu³⁺, knowing the plutonium content in the solution, determined in the first part of the solution, from the total amount of potassium dichromate, the portion spent for oxidizing plutonium is subtracted, and for the remaining amount of potassium dichromate, the uranium content is calculated.

EFFECT: providing the possibility of simplifying simultaneous determination of uranium and plutonium in mixed uranium-plutonium fuel.

1 cl, 2 tbl