METHOD FOR DECONTAMINATION OF SPENT ION-EXCHANGE RESINS CONTAMINATED WITH CESIUM AND COBALT RADIONUCLIDES Russian patent published in 2020 - IPC G21F9/28 

FIELD: nuclear power engineering.

SUBSTANCE: method for decontamination of spent ion-exchange resin contaminated with radionuclides involves treatment with highly alkaline pH≥13 decontaminating solution containing 1–3 mol/l sodium ions, cleaning the deactivating solution from cesium radionuclides on cation resin from resorcinol-formaldehyde resin and purification from cobalt radionuclides by complex formation with subsequent hydrothermal treatment. Spent ion-exchange resin is further treated with an acid deactivating solution containing a salt of ethylenediaminotetraacetic acid and amphoteric metal cations. Acid deactivating solution is passed through a resorcinol-formaldehyde resin for elution of cesium. Prior to hydrothermal cleaning of cobalt radionuclides, cobalt radionuclides are purified from selective ferrocyanide sorbent.

EFFECT: invention provides high degree of decontamination of spent ion-exchange resins and reduces volumes of secondary radioactive wastes.

1 cl, 1 dwg, 2 ex