Carrott, M. J. and Fox, O. D. and LeGurun, G. and JONES, C J and Mason, C. and Taylor, Robin and Andrieux, Fabrice and Boxall, Colin (2008) Oxidation-reduction reactions of simple hydroxamic acids and plutonium(IV) ions in nitric acid. Radiochimica Acta, 96 (6). pp. 333-343. ISSN 0033-8230
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Simple hydroxamic acids such as formo- and aceto-hydroxamic acids have been proposed as suitable reagents for the separation of either Pu and/or Np from U in modified or single cycle Purex based solvent extraction processes designed to meet the emerging requirements of advanced fuel cycles. The stability of these hydroxamic acids is dominated by their decomposition through acid hydrolysis. Kinetic studies of the acid hydrolysis of formo- and acetohydroxamic acids are reported in the absence and the presence of Pu(IV) ions. The slow reduction of these plutonium(IV) hydroxamate complexes to Pu(III) aquo-ions has been characterised by spectrophotometry and cyclic voltammetry. The reductions of Pu(IV) in the presence of FHA and AHA are consistent with a mechanism in which free hydroxamic acid in solution is hydrolysed whilst Pu(IV) ions remain fully complexed to hydroxamate ligands; then at some point close to a 1 : 1 Pu(IV) : XHA ratio, some free Pu4+ is released from the complex and reduction is initiated. Electrochemical and kinetic data suggest that the reductant is the hydroxamic acid rather than the hydroxylamine.
|Journal or Publication Title:||Radiochimica Acta|
|Uncontrolled Keywords:||Formohydroxamic acid ; Acetohydroxamic acid ; Advanced purex ; Pu(IV) reduction ; Hydrolysis ; Electrochemistry ; Actinide separations|
|Subjects:||T Technology > TA Engineering (General). Civil engineering (General)|
|Departments:||Faculty of Science and Technology > Engineering|
|Deposited On:||05 Mar 2012 09:55|
|Last Modified:||07 Jan 2015 17:13|
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