Gamma and pulsed electron radiolysis studies of CyMeinf4/infBTBP and CyMeinf4/infBTPhen: Identification of radiolysis products and effects on the hydrometallurgical separation of trivalent actinides and lanthanides

0544166 - ÚACH 2022 RIV GB eng J - Journal Article
Schmidt, H. - Wilden, A. - Modolo, G. - Bosbach, D. - Santiago-Schübel, B. - Hupert, M. - Mincher, B.J. - Mezyk, S. P. - Švehla, Jaroslav - Grüner, Bohumír - Ekberg, C.
Gamma and pulsed electron radiolysis studies of CyMeinf4/infBTBP and CyMeinf4/infBTPhen: Identification of radiolysis products and effects on the hydrometallurgical separation of trivalent actinides and lanthanides.
Radiation Physics and Chemistry. Roč. 189, DEC (2021), č. článku 109696. ISSN 0969-806X. E-ISSN 1879-0895
EU Projects: European Commission(XE) 323282 - SACSESS; European Commission(XE) 755171 - GENIORS
Institutional support: RVO:61388980
Keywords : N-Donor extractants * Nuclear waste treatment * Radiolysis * Solvent extraction * Used nuclear fuel
OECD category: Inorganic and nuclear chemistry
Impact factor: 2.776, year: 2021
Method of publishing: Open access

The radiolytic stability of the highly selective ligands CyMe4BTBP and CyMe4BTPhen against ionizing gamma radiation was studied in 1-octanol solution. CyMe4BTBP and CyMe4BTPhen are important extractants for a potential treatment of used nuclear fuel. They were studied under identical experimental conditions to directly compare the effects of gamma and pulsed electron radiolysis on the ligands and systematically study the influence of structural changes in the ligand backbone. Distribution ratios of Am3+, Cm3+ and Eu3+, the residual concentration of CyMe4BTBP and CyMe4BTPhen in solution, and the formation of radiolysis products were studied as a function of absorbed gamma dose and presence of an acidic aqueous phase during irradiation. Quantitative and semi-quantitative analyses were used to elucidate the radiolysis mechanism for both ligands. Addition products of alpha-hydroxyoctyl radicals formed through radiolysis of the 1-octanol diluent to the ligand molecules were identified as the predominant radiolysis products. These addition products also extract trivalent metal ions, as distribution ratios remained high although the parent molecule concentrations decreased. Therefore, the utilization time of a solvent using these extractants under the harsh conditions of used nuclear fuel treatment could be considerably longer than expected. Understanding the radiolysis mechanism is crucial for designing more radiation resistant extractants.
Permanent Link: http://hdl.handle.net/11104/0321217