Carrier-free $^{202}$Tl was thermally separated from proton-irradiated $^{nat}$HgO. Pressed $^{nat}$HgO targets were irradiated with ≈ 26MeV protons at the IP2 beamline of the high-intensity proton accelerator facility at the Paul Scherrer Institute. The well-known thermal decomposition of HgO at > 470 °C and the strong adsorption of Tl on a Ta surface allowed for a simple and quantitative gas-phase separation of carrier-free Tl from bulk amounts of HgO target material between 550 and 670 °C. The separation efficiency was verified by γ-spectroscopy via the main γ-emissions of $^{202}$Tl and co-produced $^{203}$Hg. This method generally provides a fast and reliable preparation of carrier-free, neutron-deficient Tl radioisotopes (e.g., medically relevant $^{201}$Tl) from a proton-irradiated $^{nat}$HgO matrix.

Journal of Radioanalytical and Nuclear Chemistry, 334 (5)

ISSN:0236-5731

ISSN:1588-2780