Radiochemical separation of Be-7 from the cooling water of the neutron spallation source SINQ at PSI

Be-7 is a key radionuclide for investigation of several astrophysical processes and phenomena. In addition, it is used as a tracer in wear measurements. It is produced in considerable amounts in the cooling water (D2O) of the Spallation Induced Neutron Source (SINQ) facility at PSI by spallation reactions on O-16 with the generated fast neutrons. A shielded ion-exchange filter containing 100 mL of the mixed-bed ion exchanger LEWATIT was installed as a bypass for the cooling water into the cooling loop of SINQ for three months. The collected activity of Be-7 was in the range of several hundred GBq. Further, the Be-7 was separated and purified in a hot-cell remotely-controlled using a separation system installed. With the exception of Be-10, radioactive by-products can be neglected, so that this cooling water could serve as an ideal source for highly active Be-7-samples. The facility is capable of producing Be-7 with activities up to 1 TBq per year. The Be-7 sample preparation is described in detail and the possible uses are discussed. In particular some preliminary results of Be-7 ion beam production are presented.