Optimization of the Processing of Mo Disks

Abstract

The objective of this work is to decrease the processing time for irradiated disks of enriched Mo for the production of 99 Mo. Results are given for the dissolution of nonirradiated Mo disks, optimization of the process for large-scale dissolution of sintered disks, optimization of the removal of the main side products (Zr and Nb) from dissolved targets, and dissolution of irradiated Mo disks.

Side-reaction products identified for photo-nuclear production of99Mo

“…Their content depends on the level of 98 Mo in the target, and for higher enrichments of 100 Mo, they should not be a concern. The removal of Zr and Nb isotopes, however, is not difficult, as coprecipitation with Fe(III) is fairly efficient [23]. It also should be noted that production of 97m Nb was not observed; only direct production of 97 Nb was detected.…”

Dissolution of Additively Manufactured Mo Disks and Structures for Accelerator Based Production of Mo-99

“…For post-irradiation processing, it is important to look at the dissolution behavior of AM Mo structures in comparison to readily dissolved press-and-sinter Mo targets. The dissolution behavior of press-and-sinter targets has been well documented in our previous reports [5][6][7][8][9][10][11]. In this report, we discuss results of dissolution experiments conducted with AM Mo disks and structures (provided by Oak Ridge National Laboratory [ORNL]) in 50% hydrogen peroxide (H2O2).…”

Molybdenum Recovery from Filters Used in Large-scale Dissolution of Sintered Mo-disks

“…The full dissolution and conversion of large 600 g batches of Mo metal disks to K2MoO4 can take approximately 2-3 hours to complete. The process begins shortly after irradiation, when Mo metal targets are placed in a hot cell for dissolution by hydrogen peroxide and conversion to potassium molybdate by an equimolar quantity of KOH [3]…”