Spectrophotometric determination of the oxygen to metal ratio during the preparation of simulated spent nuclear fuel

Abstract EN

Direct disposal was recommended as the best option for some nuclear fuels wastes.

The evaluation of the composition of these wastes is a critical aspect for the safe disposal of these wastes.

In this work, the determination of stoichiometric ratio oxygen/uranium (O/U) and oxygen/Cerium (O/Ce) in the spent fuel is predicted.

The composition of simulated high burn-up nuclear fuel (SIMFUEL) was calculated using FISPIN program.

The studied composition included uranium dioxide and fission products which were surrogated with stable elements with similar chemical behavior and with the same microstructure characteristics expected for spent nuclear fuels.

Fuel pellets were prepared, dissolved, and examined using spectorphotometirc technique.

The results reported changes that occur in the oxygen/ metal (O/M) ratio of fuel core material when it is subjected to a series of successive firing cycles.

Uranium/cerium with oxygen bonds changed from partially to wholly semimetallic.

The results concluded that stoichiometry contribute to the exact composition and properties of the spent nuclear fuel.