Title :

Multiscale structural characterizations of mixed U(IV)-An(III) oxalates (An(III) = Pu or Am) combining XAS and XRD measurements

Author(s) :

Arab-Chapelet, B. [Auteur]
CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) [CEA-DES (ex-DEN)]
Martin, M. [Auteur]
CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) [CEA-DES (ex-DEN)]
Costenoble, S. [Auteur]
CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) [CEA-DES (ex-DEN)]
Delahaye, T. [Auteur]
CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) [CEA-DES (ex-DEN)]
Scheinost, A. C. [Auteur]
Helmholtz-Zentrum Dresden-Rossendorf [HZDR]
Grandjean, S. [Auteur]
CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) [CEA-DES (ex-DEN)]
Abraham, Francis [Auteur]
Unité de Catalyse et Chimie du Solide (UCCS) - UMR 8181

Journal title :

Dalton Transactions

Abbreviated title :

Dalton Trans.

Volume number :

45

Pages :

6909-6919

Publication date :

2016-03-02

ISSN :

1477-9226

HAL domain(s) :

Chimie

English abstract : [en]

Mixed actinide(III,IV) oxalates of the general formula M2.2UIV1.8AnIII0.2(C2O4)5·nH2O (An = Pu or Am and M = H3O+ and N2H5+) have been quantitatively precipitated by oxalic precipitation in nitric acid medium (yield >99%). ...
Show more >Mixed actinide(III,IV) oxalates of the general formula M2.2UIV1.8AnIII0.2(C2O4)5·nH2O (An = Pu or Am and M = H3O+ and N2H5+) have been quantitatively precipitated by oxalic precipitation in nitric acid medium (yield >99%). Thorough multiscale structural characterization using XRD and XAS measurements confirmed the existence of mixed actinide oxalate solid solutions. The XANES analysis confirmed that the oxidation states of the metallic cations, tetravalent for uranium and trivalent for plutonium and americium, are maintained during the precipitation step. EXAFS measurements show that the local environments around U+IV, Pu+III and Am+III are comparable, and the actinides are surrounded by ten oxygen atoms from five bidentate oxalate anions. The mean metal–oxygen distances obtained by XAS measurements are in agreement with those calculated from XRD lattice parameters.Show less >

Language :

Anglais

Audience :

Internationale

Popular science :

Non

Administrative institution(s) :

Université de Lille
CNRS
Centrale Lille
ENSCL
Univ. Artois

Collections :

• Unité de Catalyse et Chimie du Solide (UCCS) - UMR 8181

Research team(s) :

Chimie, matériaux et procédés pour un nucléaire durable (CIMEND)

Submission date :

2023-05-30T16:26:56Z
2024-04-19T12:24:41Z