engleski

Characterization of the precipitates formed during the denitration of simulated HRLW

The denitration several chemical compositions of simulated HRLW (highly radioactive liquid waste) was performed using formic acid as reducing agent. Precipitates formed during the denitration of simulated HRLW were analyzed using X-ray diffraction and 57Fe Mossbauer spectroscopy. Goethite and amorphous fraction were the principal phases in these precipitates. It was found that the chemical composition of simulated HRLW and the experimental conditions of denitration have more influence on the crystallinity and the particle size than on the phase composition of the preciptates. Thermal treatment of denitrated precipitates caused the solid state transformation of goethite + amorphous fraction into hematite. The values of hyperfine magnetic field (HMF) of hematite were decreased, thus indicating the substitution of Fe3+ ions with other metal cations.

denitration ; HRLW ; formic acid ; nuclear waste

nije evidentirano