Reaction chemistry of plutonium with vanadium pentoxide in molten salts

Autor: Mary P. Neu, Donna M. Smith, Vonda R. Dole, Eduardo Garcia
Rok vydání: 2001
Předmět:
Zdroj: Journal of Alloys and Compounds. 319:258-265
ISSN: 0925-8388
DOI: 10.1016/s0925-8388(01)00874-x
Popis: Vanadium pentoxide, V2O5, has been proposed as an oxidant for the stabilization of reduced forms of plutonium within pyrochemical salt residues from plutonium pyrochemical processes at the Rocky Flats Environmental Technology Site because of its large reduction potential and its ability to react via normal solid-state reactions. However, when V2O5 was used to oxidize actual process residues results were highly variable. This paper discusses the reaction chemistry of PuCl3, Pu° and PuOCl with V2O5 under a variety of conditions, including in the presence and absence of a NaCl/KCl salt matrix. This work is the first systematic study of the solid-state oxidation of plutonium species by vanadium pentoxide. For PuCl3 a greater than or equal to 1:1 V2O5:PuCl3 ratio is needed for complete oxidation. Increasing the amount of V2O5 from 1 to 2 equivalents increases the contribution of side reactions, including reactions of V2O5 with the process equipment and/or salt matrix, and produces undesirable non-volatile ternary and quaternary vanadium compounds. The oxidation of PuOCl is similar to that of PuCl3. Greater than a 1:1 V2O5:PuOCl ratio is required to achieve adequate conversion of PuOCl to PuO2. Oxidation of Pu° by V2O5 is more complex than the PuCl3 or PuOCl oxidations. Complete oxidation of Pu° to Pu(IV) in the presence of the salt matrix does not occur with up to 6 equivalents of V2O5. However, conversion of Pu° to Pu(IV) occurs rapidly in the absence of the salt matrix.
Databáze: OpenAIRE
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