Iron Sulfide Particles for Capturing Radionuclides

There is an urgent need to remediate volatile radioactive contaminants like ¹²⁹I at nuclear cleanup locations such as Hanford. These elements are found in radioactive tank waste and may be found in the soil and groundwater. Along with established techniques, new separation techniques could improve the way purpose-designed waste forms containing these components are separated and stored. Most disposal plans explored for ¹²⁹I containing low-activity waste involve storage in underground repositories after processing. In these settings, iodine's high mobility and radiotoxicity necessitate careful management to mitigate long-term environmental impacts. Additionally, methods used to capture iodine during reprocessing are not suitable for direct disposal, requiring conversion into suitable waste forms. These waste forms aim to chemically immobilize or physically encapsulate iodine to minimize the leaching of iodine by groundwater. This study presents the synthesis and sorbing action of iron sulfide particles with forms of iodine in an aqueous environment. Iron-based magnetic nanoparticles can sorb iodine and metals from contaminated water sources, and their magnetic properties allow novel separation operations of target contaminants (e.g., I, Tc, Hg). This discussion will examine the potential of iron sulfide particles as a sorbent for capturing pollutants, such as ¹²⁹I, and investigate the efficiency of the methods to assess the feasibility of adding magnetic separation techniques into aqueous waste processing flowsheets. The used sorbents can in principle be stripped and reused or collected for a purpose-designed waste form.