Chemical processing of 123I with a modified Bio-Rex 5 resin

The Bio-Rex 5 resin was used for the recovery of ¹²³I, producedin a cyclotron by irradiation of a ¹²⁴ Xe target. Initially fouranion exchange resins AG1-X8, AG2-X8, Amberlite IRA-93 and Bio-Rex 5 wereused, but none of them gave good separations. Bio-Rex 5, consisting of a largeportion of tertiary and a smaller portion of quaternary amino groups, wasthen modified so that the resin contained only tertiary amine functional groupsand this modified resin was used for the separation. The concentrations ofiodide solutions were ca 5 ppb and the volumes about 120 ml. For measurementof iodide, ¹³¹I was added as tracer. In this study 6 columns ofvarious sizes were used and the best of them, in terms of maximum recoveryand minimum volume of NaOH for elution, was selected for routine production.