Possible Incorporation of Neptunium in Uranyl (VI) Alteration Phases

[摘要] This study examines existing data on Np behavior from both spent fuel and borosilicate glass tests in effort to resolve issues concerning the selection of possible solubility limiting phases for neptunium and the methods for detecting neptunium at low levels in spent fuel. These issues were raised in a recent report by Finch and Fortner (2002) that argues that the Np analysis with Electron Energy-Loss Spectroscopy (EELS) reported by Buck et al., (1998) is incorrect and that based on a series of experiments with Np-doped U3O8, NpO2 should be adopted as the solubility controlling phase for Np, in the Yucca Mountain performance assessment model. In this report, we will refute the claim that EELS is unable to detect Np and will suggest that the use of NpO2 as the Np solubility controlling phase is not supported by available scientific data from both spent fuel and borosilicate glass.

[发布日期] 2003-11-25 [发布机构] Pacific Northwest National Laboratory (PNNL), Richland, WA (United States), Environmental Molecular Sciences Laboratory (EMSL)

[关键词] 11 Nuclear Fuel Cycle And Fuel Materials;Environmental Molecular Sciences Laboratory;Neptunium;Spent Fuel, Eels;12 Management Of Radioactive Wastes, And Non-Radioactive Wastes From Nuclear Facilities Environmental Molecular Sciences Laboratory