title: Identification of the non-pertechnetate species in Hanford waste tanks, Tc(I)--carbonyl complexes.
abstract: Immobilization of the high-level nuclear waste stored at the Hanford Reservation has been complicated by the presence of soluble, lower-valent technetium species. Previous work by Schroeder and Blanchard has shown that these species cannot be removed by ion-exchange and are difficult to oxidize. The Tc K-edge XANES spectra of the species in Tanks SY-101 and SY-103 were reported by Blanchard, but they could not be assigned to any known technetium complex. We report that the XANES spectra are most likely those of Tc(I)-carbonyl species, especially fac-Tc(CO)3(gluconate)(2-). This is further supported by EXAFS and 99Tc-NMR studies in nonradioactive simulants of these tank wastes.
authors.affiliation: Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA. wwlukens@lbl.gov
authors.forename: Wayne W
authors.initials: WW
authors.lastname: Lukens
authors.forename: David K
authors.initials: DK
authors.lastname: Shuh
authors.forename: Norman C
authors.initials: NC
authors.lastname: Schroeder
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Ashley
mesh_terms: D002244:Carbon / Q000737:chemistry; D004784:Environmental Monitoring; D011850:Radioactive Waste / Q000032:analysis*; D012037:Refuse Disposal; D012995:Solubility; D017556:Technetium Compounds / Q000032:analysis*
chemical_list: D011850:Radioactive Waste; D017556:Technetium Compounds; D002244:Carbon