Eurobitum bituminised waste is a homogeneous mixture of 60wt% bitumen and 40 wt% of radioactive salts and precipitates stemming from the chemical reprocessing of spent nuclear fuel. The preferred option of the Belgian Agency for the Management of Radioactive Waste and Enriched Fissile Materials (ONDRAF/NIRAS) for the long-term management of this intermediate-level long-lived waste form is final disposal in a geologically stable clay formation. This requires a.o. a thorough knowledge of the long-term behaviour of Eurobitum in geological disposal conditions. The Expert Group 'Waste and Disposal' of the SCK•CEN is performing a major part of the underlying research. The work reported in this manuscript concerns the Attenuated Total Reflectance - Fourier Transformed Infra-Red spectroscopy (ATR-FTIR) of non-radioactive Eurobitum, to verify or to complement research work performed before. The results confirm that oxidation with incorporation of oxygen in the bitumen compounds does not take place when bituminous samples are heated in the absence of oxygen. Additionally, based on the ATR-FTIR spectroscopy results of bituminous samples with well-known NaNO3 and CaSO4 content, calibration curves were established to calculate from a simple ATR-FTIR spectrum the NaNO3 and CaSO4 content of samples for which these values are not (well) known.
|Place of Publication
|Published - Aug 2009