this work we report on new examples of phenanthrolindiamides containing asymmetric centers in amide substituents.The synthesized ligands are expected to have complex thermodynamic behavior.Their structure was unambigu...this work we report on new examples of phenanthrolindiamides containing asymmetric centers in amide substituents.The synthesized ligands are expected to have complex thermodynamic behavior.Their structure was unambiguously confirmed by a combination of spectral analysis methods and X-ray analysis.It is shown that the obtained ligands form complexes with nitrates of rare-earth elements,and the stability constants of such complexes in acetonitrile solution were also measured.The performed solvent extraction tests revealed a significant effect of methyl groups in cyclic amide substituents on the distribution ratios and selectivity factors in the lanthanides(III)and Am(III)series in comparison with the previously studied ligands based on unsubstituted pyrrolidine.The observed effects are explained from the standpoint of quantum chemistry calculations taking into account possible stereoisomerism.展开更多
Closing the nuclear fuel cycle is a key objective in the development of Generation IV nuclear systems,enabling the recycling of actinides and reducing the long-term radiotoxicity of nuclear waste.Americium is a prime ...Closing the nuclear fuel cycle is a key objective in the development of Generation IV nuclear systems,enabling the recycling of actinides and reducing the long-term radiotoxicity of nuclear waste.Americium is a prime candidate for transmutation,but its effective use requires high-purity separation from chemically similar curium and lanthanides.In this work,we report the design,synthesis,and evaluation of a novel extractant,4,7-dicyano-N,N’-diethyl-N,N’-diphenyl-1,10-phenanthroline-2,9-dicarboxamide(DAPhenCN),for selective separation of Am(Ⅲ)from Cm(Ⅲ).This extractant was selected for synthesis based on the DFT modeling results of the complexes of 4-and 7-disubstituted 1,10-phenanthroline-2,9-dicarboxamides with Am(Ⅲ),Cm(Ⅲ)and lanthanides(Ⅲ).Solvent extraction experiments revealed Am/Cm separation factors(SFAm/Cm)of 5–6,with favorable distribution ratios for counter-current processing.Crucially,DAPhenCN demonstrated excellent resistance to hydrolysis and radiolysis underα-,γ-,and electron-beam irradiation.Counter-current tests using real raffinates from VVER-1000 spent nuclear fuel reprocessing confirmed the robustness and efficiency of the extraction system,achieving>99%americium recovery and>99.9%curium purity.Light lanthanides partially co-extracted with Am(Ⅲ),while heavier ones had no significant impact.The developed process enables the production of curium-free americium suitable for transmutation fuel fabrication,advancing the implementation of closed nuclear fuel cycles.展开更多
基金Synthetic part of this work and quantum chemical calculations was supported by RSF(grant no.21-73-10067).
文摘this work we report on new examples of phenanthrolindiamides containing asymmetric centers in amide substituents.The synthesized ligands are expected to have complex thermodynamic behavior.Their structure was unambiguously confirmed by a combination of spectral analysis methods and X-ray analysis.It is shown that the obtained ligands form complexes with nitrates of rare-earth elements,and the stability constants of such complexes in acetonitrile solution were also measured.The performed solvent extraction tests revealed a significant effect of methyl groups in cyclic amide substituents on the distribution ratios and selectivity factors in the lanthanides(III)and Am(III)series in comparison with the previously studied ligands based on unsubstituted pyrrolidine.The observed effects are explained from the standpoint of quantum chemistry calculations taking into account possible stereoisomerism.
基金support from the State Atomic Energy Corporation Rosatom.
文摘Closing the nuclear fuel cycle is a key objective in the development of Generation IV nuclear systems,enabling the recycling of actinides and reducing the long-term radiotoxicity of nuclear waste.Americium is a prime candidate for transmutation,but its effective use requires high-purity separation from chemically similar curium and lanthanides.In this work,we report the design,synthesis,and evaluation of a novel extractant,4,7-dicyano-N,N’-diethyl-N,N’-diphenyl-1,10-phenanthroline-2,9-dicarboxamide(DAPhenCN),for selective separation of Am(Ⅲ)from Cm(Ⅲ).This extractant was selected for synthesis based on the DFT modeling results of the complexes of 4-and 7-disubstituted 1,10-phenanthroline-2,9-dicarboxamides with Am(Ⅲ),Cm(Ⅲ)and lanthanides(Ⅲ).Solvent extraction experiments revealed Am/Cm separation factors(SFAm/Cm)of 5–6,with favorable distribution ratios for counter-current processing.Crucially,DAPhenCN demonstrated excellent resistance to hydrolysis and radiolysis underα-,γ-,and electron-beam irradiation.Counter-current tests using real raffinates from VVER-1000 spent nuclear fuel reprocessing confirmed the robustness and efficiency of the extraction system,achieving>99%americium recovery and>99.9%curium purity.Light lanthanides partially co-extracted with Am(Ⅲ),while heavier ones had no significant impact.The developed process enables the production of curium-free americium suitable for transmutation fuel fabrication,advancing the implementation of closed nuclear fuel cycles.
