Initial Assessment of Alternate Metals in Chalcogels

Consolidation of Tin Sulfide Chalcogels and Xerogels with and without Adsorbed Iodine

“…Chalcogels are aerogels that can be made from a variety of chalcogenide building blocks. − These materials have a selective affinity for various heavy metals and gases. ,,,,,− A summary of the more commonly studied chalcogel chemistries is provided in Table . Recent work has shown that chalcogels can capture large quantities of iodine at >2 g g –1 of the starting sorbent. ,,− These sorbents are under development as an alternative to metal–organic frameworks , and the more widely studied silver-exchanged zeolite (AgZ) , for capturing radioiodine ( 129 I and 131 I) that is generated during nuclear fission of uranium fuel and released during used fuel reprocessing.…”

Initial Assessment of the Consolidation of Chalcogels into a Viable Waste Form

“…Different methods have been discovered to make these chalcogels including (1) the aggregation of nanoparticles and (2) the chemical linkage of chalcogenido clusters with an interlinking metal (or metals). A comprehensive summary is provided in Table 1 (Riley et al, 2012). (Polychronopoulou et al, 2012) At the Pacific Northwest National Laboratory (PNNL), we have been studying these materials as sorbents for the radioiodine evolved during the proposed reprocessing of used nuclear fuel.…”

“…While the concentrations of iodine are low, the required capture efficiencies are very high at ≥99.4% (40 CFR 190, 2012). The initial chalcogel materials tested at PNNL to date show promise as sorbents with >99% capture efficiencies for low iodine concentrations in air (Riley et al, 2011;Riley et al, 2012).…”