JRP CALL information
Supported By

European Commission

Short description of the work

The structure of Tc complexes after interaction of Tc species at selected oxidation states with Np(III and VI) has been studied by EXAFS. For this studies 4 samples containing Tc with Np and 2 samples containing only TcO4- and Tc(IV) as a references were prepared at HZDR in Dresden. The Tc K-edge EXAFS spectra of all solutions were recorded using a fluorescence detector. The energy scales for XANES scans for Tc and Np were calibrated with Mo (Mo K-edge at 20000 eV) and Y (Y K-edge at 17038 eV) metals foils respectively.
The spectra of Tc compounds in the samples containing initially Tc(IV) and Tc(III,IV) species with NpO22+ showed characteristic for pertechnetates inflection point of pre-edge absorption peak at 21044 eV. The experimental results were confirmed by the theoretical fit to this data. Tc is surrounded by 4 oxygen atoms (N = 3.9) at a distance of 1.74 Å (σ2 = 0.0010 Å2). The EXAFS spectrum of Tc compound in the sample containing initially Tc(IV) and reduced Np ions suggest the existence of hydrated TcO2 and neptunium at +IV and +VI oxidation states.

Main visitor contact data
Name: Dr Maciej Chotkowski
Organisation: Univewrsity of Warsaw

JRP Identification
JRP nr: TALI-C05-11
JRP title: Interaction of technetium(III and III,IV) with neptunium in acidic media
JRP scope: Scope 1: Actinide separation chemistry

Visited Associated Pooled Facility
Visited APF during the stay: HZDR - ROBL
Name of the APF Contact Person: Dr Andreas Scheinost

Other APF and organisation involved in the JRP
Other organisations involved:
Other APF involved in the project: HZDR - IRE

Description of the work done at the associated pooled facility
Start date of the stay: 7/15/2015
End date of the stay: 7/18/2015
Quantity of access: 9
Access Unit: Shifts
Misc.: Work during week-ends

Other APF visitors of the JRP during the stay
Visitor 2: Wiktor Saczawa
Visitor 3:
Visitor 4:
Visitor 5: