Separation and purification of 131I from neutron irradiated tellurium dioxide targets by wet-distillation method

Abstract Separation and purification of carrier-free 131 I by the wet-distillation method from thermal neutron irradiated tellurium dioxide targets along with their Al wrappers in 8N H 2 SO 4 , HNO 3 and HCl acid solutions containing H 2 O 2 and refluxing for 3 h is investigated. The distilled off 131 I is absorbed in a mixture solution of NaOH + Na 2 S 2 O 3 after passing through 0.5N H 2 SO 4 acid filter. The corresponding 131 I separation factor, recovery yield and percentage trapped in the acid filter and radionuclidic, radiochemical and chemical purity indices and discussions favour the use of H 2 SO 4 acid as the distillation medium. The corresponding separation and purification indices of 131 I are investigated as a function of chemical composition of the distillation medium (e.g., concentration of H 2 SO 4 , kind and concentration of the oxidant, the sequence of addition of H 2 SO 4 /H 2 O 2 , chemical impurities and catalyst), chemical composition of the acid filter (e.g., concentration of H 2 SO 4 and additives such as H 2 O 2 and oxalic acid) and radioiodine carrier-gas (e.g., air and nitrogen). By applying the recommended separation and purification procedure, 131 I product solution of high separation, recovery and purity indices is obtained.