An improved Re/W separation protocol for preparation of carrier-free 186Re

An Al2(WO4)3 target bombarded with a proton beam (28.5 MeV, 20 μA) for 1 hour was completely dissolved in about 5 ml of hot 2N NaOH and the clear solution was neutralized with 2N HCL. The resulted white precipitate of Al2(WO4)3 can be separated from the solution by centrifugation and decantation. The supernatant containing radioactive Re as ReO4- was loaded onto a column (1 cm x 10 cm) of activated alumina (100-200 mesh). Eluted with 10 ml of saline, the carrier-free ReO4- was collected, while the small amount of Al2(WO4)3 in the supernatant was adsorbed on the column. The total yield of ReO4- was 94.7% and the breakthrough of WO42- only 1.0 x 10-6 M. The whole separation process can be accomplished within 30 minutes. This rapid and efficient Re/W separation protocol is applicable to the preparation of carrier-free 186Re, when an enriched Al2(186WO4)3 target is used. (author)