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"Isotope harvesting" is a technique that offers access to exotic radionuclides created as by-products during nuclear science research. Ongoing exploratory work at the National Superconducting Cyclotron Laboratory (NSCL) is directed towards the production and extraction of rare radionuclides from a flowing-water target and intends to pave the way for future harvesting efforts at the upcoming Facility for Rare Isotope Beams (FRIB). Here we present the collection of 62Zn from an aqueous matrix irradiated with a 150 MeV per nucleon 78Kr beam, while synergistically capturing other gaseous reaction products. In addition to the production rate for 62Zn (9.08(30) × 10−5 62Zn per incoming 78Kr), the rates of formation for several other radionuclides were determined as well. The purification of 62Zn from a large number of co-produced radionuclides was performed by anion exchange chromatography, allowing the isolation of 80.5(5.2)% of the generated 62Zn. With the decay of 62Zn the radioactive daughter 62Cu is generated, and with the isolation of pure 62Cu eluate, the principle of a medical radionuclide generator could be demonstrated. To illustrate the applicability of the obtained 62Zn, the isolated product was used in free and DTPA-labelled form in a proof of principle plant uptake study with garden cress employing phosphor imaging for visualization. [ABSTRACT FROM AUTHOR]

Tungsten is a commonly used material at many heavy-ion beam facilities, and it often becomes activated due to interactions with a beam. Many of the activation products are useful in basic and applied sciences if they can be recovered efficiently. In order to develop the radiochemistry for harvesting group (IV) elements from irradiated tungsten, a heavy-ion beam containing 88Zr was embedded into a stack of tungsten foils at the National Superconducting Cyclotron Laboratory and a separation methodology was devised to recover the 88Zr. The foils were dissolved in 30% hydrogen peroxide, and the 88Zr was chemically purified from the tungsten matrix and from other co-implanted radionuclides (such as 85Sr and 88Y) using strong cation-exchange (AG MP-50) chromatographic resin in sulfuric acid media. The procedure provided 88Zr in approximately 60 mL 0.5 M sulfuric acid with no detectable radio-impurities. The overall recovery yield for 88Zr was (92.3 ± 1.2)%. This proof-of-concept experiment has facilitated the development of methodologies to harvest from tungsten and tungsten-alloy parts that are regularly irradiated at heavy-ion beam facilities. • Proof-of-concept solid-phase isotope harvesting from tungsten collectors. • Solid-phase isotope harvesting for high recoveries of 88Zr from irradiated W foils. • Solid-phase isotope harvesting has higher recovery efficiency than aqueous-phase harvesting for 88Zr. • Radiochemical methods for extracting trace impurities from tungsten and tungsten-alloy parts were developed. [ABSTRACT FROM AUTHOR]

During routine operation of the Facility for Rare Isotope Beams (FRIB), radionuclides will accumulate in both the aqueous beam dump and along the beamline in the process of beam purification. These byproduct radionuclides, many of which are far from stability, can be collected and purified for use in other scientific applications in a process called isotope harvesting. In this work, the viability of 88Zr harvesting from solid components was investigated at the National Superconducting Cyclotron Laboratory. A secondary 88Zr beam was stopped in a series of collectors comprised of Al, Cu, W, and Au foils. This work details irradiation of the collector foils and the subsequent radiochemical processing to isolate the deposited 88Zr (and its daughter 88Y) from them. Total average recovery from the Al, Cu, and Au collector foils was (91.3 ± 8.9) % for 88Zr and (95.0 ± 5.8) % for 88Y, respectively, which is over three times higher recovery than in a previous aqueous-phase harvesting experiment. The utility of solid-phase isotope harvesting to access elements such as Zr that readily hydrolyze in near-neutral pH aqueous conditions has been demonstrated for application to harvesting from solid components at FRIB. • Proof-of-concept solid-phase isotope harvesting demonstrated at the NSCL. • Solid-phase isotope harvesting for improved recoveries of Zr. • High recoveries of 88Zr and 88Y from Al, Cu, and Au foils irradiated with 88Zr beam. • Provides a framework for harvesting group IV elements from FRIB. [ABSTRACT FROM AUTHOR]