METHOD OF DISSOLVING VOLOXIDATED IRRADIATED NUCLEAR FUEL Russian patent published in 2017 - IPC G21F9/28 

FIELD: chemistry.

SUBSTANCE: invention can be used in the processing of spent nuclear fuel (SNF) of nuclear power plants (NPPs) at dissolution operations. The SNF process includes treatment with a nitrogen dioxide system. The calculated amount of a solution of hydrogen peroxide and nitrogen tetroxide is brought into contact with the loading of the dissolving material at a temperature of 0.5-14.5°C, the reaction mixture is heated in a closed system to the dissolution temperature at a rate of 0.1-1.8°C/min, dissolution is carried out at a temperature of 71-98°C and an overpressure of 0.05-0.45 MPa with the supply of an oxygen-containing gas stream into the system in a continuous or batch mode at a pressure of up to 0.49 MPa. The invention makes it possible to obtain a liquid stable at a temperature of 60-75°C product with a concentration of uranium 550-1100 g/l and nitric acid 0.8-3.5 mol/l.

EFFECT: improved properties and increased stability.

9 cl, 3 ex