RADIOLYTIC DEGRADATION OF A CROWN ETHER FOR EXTRACTABILITY OF STRONTIUM

Dicyclohexano-18-crown-6 (DC18C6), dissolved in chloroform, 1octanol, toluene or cyclohexane, was irradiated by 60Co gamma-rays. Radiolytic destruction of DC 18C6, measured by gas chromatography, decreased in the order : chloroform > cyclohexane > 1-octanol > toluene. Distribution coefficients in the solvent extraction of strontium from nitric acid solution were measured. These distribution coefficients were minimally affected by gamma-irradiation in toluene solution, but decreased with the absorbed dose in chloroform solution. It was suggested that the distribution coefficient for the liquid-liquid extraction system was influenced by radiolytic products. The effect of radiolytic products on the distribution coefficients was evaluated by considering DC18C6 remaining in the organic phase after irradiation. The distribution coefficient measured for the organic phase with radiolytic products was larger than that without radiolytic products. The radiolytic products were thus shown to contribute to the increase in the distribution coefficient.