Determination of silver fission product in high-temperature nuclear reactor fuels by ion-exchange separation and γ-counting

The content of silver fission product and its radial distribution in spherical coated fuel particles can be measured by stepwise chemical removal of pyrolytic carbon layers coupled with an anion-exchange separation procedure and subsequent γ-counting. An adsorption efficiency better than 98% ranging over five orders of magnitude in silver concentration was found for a bromide-containing medium. Silver to carbon ratios down to 10^-12 are measurable so that this method is useful for studying the diffusion of silver in pyrolytic carbon.