New Diamides of 2,2′-dipyridyl-6,6′-dicarboxylic Acid for Actinide-Lanthanide Separation

Screening of the Structure of Americium Extractants Based on a 2,2’‐Bipyridyl Scaffold: a Simple Way to a N2,O2‐Tetradentate Ligands Library for Rational Design of An/Ln Extractants

“…However, the separation of americium by diamides of 2,2’‐bipyridine‐6,6’‐dicarboxylic acid follows the same trends as CMPO molecules. Introducing the aromatic ring into the amidic moiety shows sharp increases in metal distribution coefficients, and the subsequent substitution of the aromatic ring with alkyl groups also improves the extraction ,. The distribution coefficients demonstrate a tenfold rise when going from N ‐ethylanilide to N‐ethyl‐ p‐ alkylanilides of 2,2’‐bipyridine‐6,6’‐dicarboxylic acid .…”

“…Introducing the aromatic ring into the amidic moiety shows sharp increases in metal distribution coefficients, and the subsequent substitution of the aromatic ring with alkyl groups also improves the extraction ,. The distribution coefficients demonstrate a tenfold rise when going from N ‐ethylanilide to N‐ethyl‐ p‐ alkylanilides of 2,2’‐bipyridine‐6,6’‐dicarboxylic acid . The effect on metal affinity of a substituent in the pyridine ring was studied for 6,6’‐bis(1,2,4‐triazin‐3‐yl)‐2,2’‐bipyridine‐type (BTBP) and 2,9‐bis(1,2,4‐triazin‐3‐yl)‐phenanthroline‐type (BTPhen) compounds, but not for heterocyclic diamides.…”

“…Moreover, the BTP‐type ligands show increase in both the americium distribution and Am/Eu selectivity with the aliphatic side chain elongation for tetrachloroethylene and dodecane solvents and the opposite dependence for the ionic liquids solvents . The studies of americium separation by diamides of 2,2’‐bipyridine‐6,6’‐dicarboxylic acid previously were made in two general types of extraction mixtures: part of the compounds were investigated in pure meta ‐trifluoromethylnitrobenzene (F‐3) and several types of ligands were tested in presence of different amounts of chlorinated cobalt dicarbolide, (CCD), a well known lipophilic anion for increase the metal separation. The addition of CCD about tenfold increases the Am separation efficiency ,.…”

“…The studies of americium separation by diamides of 2,2’‐bipyridine‐6,6’‐dicarboxylic acid previously were made in two general types of extraction mixtures: part of the compounds were investigated in pure meta ‐trifluoromethylnitrobenzene (F‐3) and several types of ligands were tested in presence of different amounts of chlorinated cobalt dicarbolide, (CCD), a well known lipophilic anion for increase the metal separation. The addition of CCD about tenfold increases the Am separation efficiency ,. As the metal extraction is the solvent dependent, the universal platform for the comparison of the properties of the extractants is required for systematic comparison of their properties in conjunction with separation behaviour.…”

Combined Experimental and Density Functional Theoretical Studies of Am3+ and Eu3+ Extraction and Complexation with Different Nitrilotriacetamide (NTA) Derivatives

“…Various classes of soft donor ligands have their own limitations and advantages . Mixed soft‐hard donor ligands have been explored and found to be promising for this An/Ln separation . Hexaalkylnitrilotriacetamides (HRNTA, Figure ) represent a class of mixed ‘N’,’O’ donor ligands, where the ‘N’ atoms present at the centre of the ligand structure can also participate along with the carbonyl ‘O’ atoms of the amide groups.…”