Irradiation of strontium chloride targets at proton energies above 35 MeV to produce PET radioisotope Y-86

Abstract

Proton irradiation of natural and enriched SrCl₂ targets was used to produce PET radioisotope ⁸⁶Y. The proton energy was degraded from the incident 117.8 MeV to induce the ⁸⁸Sr(p,3n) reaction. For the irradiation three pellets made of ^natSrCl₂ (6.61 and 74.49 g) and ⁸⁸SrCl₂ (5.02 g) were pressed and individually encapsulated in stainless steel target bodies. The two smaller targets were irradiated for 0.5–1 h at the energy ∼ 46→37 MeV to take advantage of the peak in the excitation function of the ⁸⁸Sr(p,3n) reaction. The larger target was irradiated at 66.4→44.6 MeV. The irradiated pellets were chemically processed to selectively separate ⁸⁶Y radioisotope using Eichrom DGA (N,N,N´,N´-tetra-n-octyldiglycolamide) resin. The production yields of ⁸⁶Y were determined to be 10–13 mCi/μA h. Coproduction of ^87mY in the final product was 34% for ^natSrCl₂ and 54% for ⁸⁸SrCl₂ target. The chemical separation yield of yttrium reached 88–92%. The developed chemical procedure allows for the same day processing and shipment of the isotope to users.