Preparation of 1 Ci of europium 155 without carrier

High activity 'point' sources of 155Eu are used for medical and industrial applications. For this purpose we have studied a method of obtaining I Ci of carrier free 155Eu, with a solid residue smaller than 5 mg per Ci. In order to separate the 155Eu from several grams of a 154Sm enriched target we propose a procedure which is based on the work of Bouissieres and David, Onstott, and Takekoshi et al. The separation is carried out by electrolysis on a mercury cathode followed by purification on ion exchange resin. The yields of the europium separation and target recovery are 80 per cent and 90 per cent respectively. The time required for the procedure is three days. (authors)