Contribution to the determination of total hydrogen in oxide nuclear fuels

Normally the total hydrogen content of a fast breeder mixed oxide fuel is calculated from the results of the determinations of free hydrogen and water. Thermodynamic considerations, coupled with kinetic results for room temperature and 10000C and taken from the literature indicate, that the normal method for the determination of water by heating in a carrier gas stream and subsequent coulometric determination of the expelled water must give low results. A modification of this method involving the introduction of a copper oxide furnace into the system for the oxidation of hydrogen has been studied. The resulting method for the determination of total hydrogen gives about ten times higher values than those calculated from the normal water determination. These total hydrogen values and the oxygen to metal ratios which are obtained by gravimetric methods and not corrected for the water content, reflect more realistically the in-pile conditions in the fuel pin. (Auth.)