Radiochemical studies relevant to the production of 86Y and 88Y at a small-sized cyclotron

Excitation functions were measured by the stacked-foil technique for natSr(p,xn)88,87m,gY reactions from threshold up to 25 MeV. From the measured cross sections integral yields of 88Y, 87mY and 87gY were calculated. The optimum energy range for the production of 88Y is Ep=14→9 MeV; the 88Y yield amounts to 1.75 MBq (47.3 μCi/μA.h) and the 87Y and 87mY impurities to 2.0 and 4.4%, respectively. The isomeric cross section ratio for the pair 87m,gY was determined as a function of incident proton energy and the results are discussed in terms of the spins of the two isomeric states involved. Medium scale production of both 86Y and 88Y has been carried out more than 15 times each using the (p,n) reaction. In the former case 96.3% enriched 86SrCO3 was used as target material, and in the latter natSrCO3. The method of separation of radioyttrium has been improved. After coprecipitation with La(OH)3, cation-exchange HPLC was applied to isolate radioyttrium from the carrier lanthanum. The radionuclidic and chemical purities of the products were good. Batch yields of 86Y and 88Y amounted to about 3.5 GBq and 35 MBq, respectively