JRP CALL information
Supported By

European Commission

Short description of the work

Preliminary search for extractable mixed-ligand Am(III), Cm(III) and Eu(III) complexes in solvent extraction systems with lipophilic TODGA and hydrophilic SO3-Ph-BTP4– ligands, carried out using TRLFS (Time Resolved Laser Fluorescence Spectroscopy) studies with TEDGA – a hydrophilic homologue of TODGA – allows to detect the heteroleptic TEDGA / SO3-Ph-BTP complexes of Cm(III) and Eu(III) in dilute aqueous solutions. In the first step, the formation of heteroleptic complexes was studied in monophasic experiments. An aqueous solution containing SO3-Ph-BTP and Cm(III) [analogue of Am(III)] ions in 1 mmol/L HClO4 was titrated with N,N,N',N'-tetraethyl diglycolamide (TEDGA), a water soluble homologue of lipophilic TODGA. The following complexes were identified by their distinct emission spectra: Cm(III)(SO3-Ph-BTP), Cm(III)(TEDGA), Cm(TEDGA)2, Cm(TEDGA)3 and moreover two unknown yet heteroleptic complexes, Cm(III)(TEDGA)m(SO3-Ph-BTP)n. The heteroleptic complexes were identified as Cm(III)(TEDGA)(SO3-Ph-BTP) and Cm(III)(TEDGA)2(SO3-Ph-BTP) by slope analysis. In the second step, post extraction organic phases were examined. This was done by extracting Cm(III) or Eu(III) from an aqueous phase containing 20 mmol/L SO3-Ph-BTP in 0.5 mol/L HNO3 into an organic phase (0.2 mol/L TODGA + 5% 1-octanol in kerosene) and recording the Cm(III) or Eu(III) emission spectra of the organic phase samples. Unfortunately, only the emission spectrum of the respective M(III)(TODGA)3 complex was detected, no additional features from heteroleptic complexes were observed. Furthermore, Eu(III) excitation spectra were recorded. One sample was a blank organic phase, the other one was loaded with Eu(III) by extracting from an aqueous phase containing 30 mmol/L Eu(NO3)3 and 20 mmol/L SO3-Ph-BTP in 0.5 mol/L HNO3. Again, only the emission spectra of the Eu(III)(TODGA)3 complexes were detected regardless of the excitation wavelength. In conclusion, we could prove that heteroleptic DGA/SO3-Ph-BTP complexes do form; however, we were not able to detect them in the organic phase in the extraction experiments so far. This may be due to their being present only at relatively low concentrations as compared to the M(III)(TODGA)3 complexes.

Main visitor contact data
Name: Dr Irena Herdzik-Koniecko
Organisation: Institute of Nuclear Chemistry and Technology; Dorodna 16;Warsaw 03-195; Poland

JRP Identification
JRP nr: TALI-C06-15
JRP title: TRLFS search of heteroleptic Cm(III)/Eu(III) complexes with TODGA and SO3-Ph-BTP ligands in solvent extraction systems
JRP scope: Scope 1: Actinide separation chemistry

Visited Associated Pooled Facility
Visited APF during the stay: KIT-INE - Laboratories
Name of the APF Contact Person: Dr Andreas Geist

Other APF and organisation involved in the JRP
Other organisations involved:
Other APF involved in the project:

Description of the work done at the associated pooled facility
Start date of the stay: 8/17/2015
End date of the stay: 8/28/2015
Quantity of access: 10
Access Unit: Days