Use of iron sulfide for removing polonium from liquid radioactive waste

Immobilization of polonium from low-level liquid radioactive waste (LRW) on iron monosulfide in batch and dynamic modes was studied. In batch experiments, the Po immobilization on FeS increases with increasing pH. At the solid phase: solution weight ratio of 1: 100, the degree of 210Ро removal from the solution in 2 days is 72.6% at pH 5.45 and 92.8% at pH 6.20. In filtration of LRW with pH 3–4 through a bulk filter of iron monosulfide dispersed in aluminosilicate gel and quartz sand, more than 99.4% of 210Ро is removed from the LRW volume exceeding the volume of the sulfide gel material by a factor of approximately 700. Iron monosulfide can be used for efficient removal of Po from low-level LRW.