Radical switching Am/Eu selectivity in sterically restricted diglycolamides.
Mikhail A Kalinin1, Mariia V Evsiunina1, Paulina Kalle2
1Department of Chemistry, Lomonosov Moscow State University, Leninskie gory 1 bld. 3, 119991 Moscow, Russia. chem.kalinin@gmail.com.
Dalton Transactions (Cambridge, England : 2003)
|July 1, 2026
Summary
Researchers developed new bisoxolactams for separating americium(III) and europium(III). Ligand tuning, including adding bulky groups, controls extraction efficiency and preference.
Area of Science:
- Coordination Chemistry
- Separation Science
- Radiochemistry
Background:
- Separation of trivalent actinides (Am) and lanthanides (Eu) is crucial for nuclear fuel reprocessing.
- Developing selective extractants is key to efficient Am/Eu separation.
Purpose of the Study:
- To synthesize novel bisoxolactams as potential extractants.
- To investigate their efficacy in separating Americium(III) and Europium(III).
- To understand how ligand structure influences extraction selectivity.
Main Methods:
- Synthesis of eight new bisoxolactams from 5-valerolactone and amines.
- Development of a protocol for symmetrical and asymmetrical extractant preparation.
- Extraction experiments to evaluate Am(III) and Eu(III) separation.
Main Results:
- Successful preparation of novel bisoxolactam extractants.
- Demonstrated tunability of extraction efficiency by adjusting ligand softness.
- Identified that bulky tert-butyl groups reverse selectivity, favoring Am(III) over Eu(III).
Conclusions:
- Bisoxolactams are effective extractants for Am(III)/Eu(III) separation.
- Ligand design, particularly steric hindrance, is a powerful tool for controlling separation factors.
- This work offers a pathway to improved nuclear waste management strategies.
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