Hydrogen catalytic effects of nanostructured alloy particles in spent fuel on radionuclide immobilization

• For the first time, hydrogen catalytic effects of fission product alloy particles nondestructively extracted from spent nuclear fuel were demonstrated. The redox sensitive radionuclides at oxidized forms Se(IV), Tc(VII), U(VI), Np(V) and Pu(VI) were found to be stable in a solution saturated with a gas mixture (Ar + 10% H-2 + 0.03% CO2) but rapidly immobilized in the same solution when contacted with the particles. In comparison, a synthetic alloy sample with similar elemental composition as the alloy particles generated in nuclear fuel displayed a smaller, but unequivocal catalytic effect. The smaller catalytic effect of synthetic alloy was apparently enhanced by a P-radiation source. The information obtained in this work contributes to improved understanding of the redox chemistry of radionuclides in nuclear waste geologic repository environments and, in particular, of the catalytic properties of these unique alloy particles.

Ämnesord

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Miljövetenskap (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Environmental Sciences (hsv//eng)

Nyckelord

Radioactive catalyst

Nanoparticle

Hydrogen

Fission product

Nuclear waste

Environmental chemistry

Miljökemi

miljökemi

Environmental Chemistry

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)