The synthesis, lanthanide complexation, and solvent extraction of actinide(III) lanthanide(III) radiotracers from nitric acid solutions by a phenanthroline-derived quadridentate bis-triazine ligand are described. separates Am(III) Cm(III) the lanthanides with remarkably high efficiency, selectivity, fast kinetics compared to its 2,2′-bipyridine counterpart. Structures 1:2 bis-complexes Eu(III) Yb(III) were elucidated X-ray crystallography force field calculations, respectively. bis-complex...

The removal of the most long-lived radiotoxic elements from used nuclear fuel, minor actinides, is foreseen as an essential step toward increasing public acceptance energy a key component low-carbon future. Once removed remaining these can be fuel in their own right fast reactors or converted into shorter-lived stable by transmutation prior to geological disposal. SANEX process proposed carry out this selective separation solvent extraction. Recent efforts develop reagents capable separating...

Two members of the tetradentate N-donor ligand families 6,6'-bis(1,2,4-triazin-3-yl)-2,2'-bipyridine (BTBP) and 2,9-bis(1,2,4-triazin-3-yl)-1,10-phenanthroline (BTPhen) currently being developed for separating actinides from lanthanides have been studied. It has confirmed that CyMe4-BTPhen 2 faster complexation kinetics than CyMe4-BTBP 1. The values HOMO-LUMO gap are comparable with those 1 which was previously calculated to be 2.13 eV. displacement BTBP its bis-lanthanum(III) complex by...

Tetrasulfonated bis-1,2,4-triazine ligands can selectively complex and separate actinides from lanthanides in aqueous nitric acid with very high selectivities.

Lanthanide(III) complexes with N-donor extractants, which exhibit the potential for separation of minor actinides from lanthanides in management spent nuclear fuel, have been directly synthesized and characterized both solution solid states. Crystal structures Pr(3+), Eu(3+), Tb(3+), Yb(3+) 2,9-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-1,2,4-benzotriazin-3-yl)-1,10-phenanthroline (CyMe4-BTPhen) Tb(3+) 6,6'-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-1,2,4-benzotriazin-3-yl)-2,2'-bypyridine...

This account summarizes recent work by us and others on the development of ligands for separation actinides from lanthanides contained in nuclear waste streams context a future European strategy management. The current status actinide/lanthanide separations worldwide is briefly discussed, synthesis, development, testing different classes heterocyclic soft N- S-donor Europe over last 20 years presented. has led to benchmark ligand that displays many desirable qualities industrial use....

The direct selective separation of the trivalent actinides americium and curium from a simulated Plutonium Uranium Refining by EXtraction (PUREX) raffinate solution continuous counter-current solvent extraction process using miniature annular centrifugal contactors was demonstrated on laboratory scale. In 32-stage spiked test (12 stages for extraction, 16 scrubbing, 4 Am/Cm stripping), an extractant mixture CyMe4BTBP TODGA in TPH/1-octanol used. co-extraction some fission corrosion product...

An americium(III) selective separation procedure was developed based on the coextraction of trivalent actinides (An(III)) and lanthanides (Ln(III)) by TODGA (N,N,N′,N′-tetraoctyl-diglycolamide), followed Am(III) stripping using hydrophilic complexing agent TS-BTPhen (3,3′,3ʺ,3ʺ′-[3-(1,10-phenanthroline-2,9-diyl)-1,2,4-triazine-5,5,6,6-tetrayl]tetrabenzenesulfonic acid). Distribution ratios were found at an acidity 0.65 mol L−1 nitric acid that allowed for from Cm(III) (DCm > 1; DAm < 1),...

Abstract Four new 6,6′‐bis(1,2,4‐triazin‐3‐yl)‐2,2′‐bipyridine (BTBP) ligands, which contain either additional alkyl groups on the pyridine rings or seven‐membered aliphatic attached to triazine rings, have been synthesized, and effects of substitution in 4‐ 4′‐positions their extraction properties with Ln III An cations simulated nuclear waste solutions studied. The speciation ligand 13 some trivalent lanthanide nitrates was elucidated by 1 H NMR spectroscopic titrations ESI‐MS. Although...

The synthesis, lanthanide complexation and solvent extraction of An(III) Ln(III) radiotracers from nitric acid solutions by a pre-organized, phenanthroline-derived bis-triazine ligand CyMe4-BTPhen are described. It was found that the separated Am(III) Cm(III) lanthanides with remarkably high efficiency, selectivity, faster kinetics compared to its 2,2'-bipyridine counterpart CyMe4-BTBP. origins ligands properties were established combination experiments, X-ray crystallography, surface...

While the etiology of non-familial Parkinson's disease (PD) remains unclear, there is evidence that increased levels tissue iron may be a contributing factor. Moreover, exposure to some environmental toxicants considered an additional risk Therefore, brain-targeted chelators are interest as antidotes for poisoning with dopaminergic toxicants, and potential treatment PD. We, therefore, designed series small molecules high affinity ferric containing structural elements allow their transport...

The quadridentate N-heterocyclic ligand 6-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-1,2,4-benzotriazin-3-yl)-2,2′ : 6′,2′′-terpyridine (CyMe4-hemi-BTBP) has been synthesized and its interactions with Am(III), U(VI), Ln(III) some transition metal cations have evaluated by X-ray crystallographic analysis, Am(III)/Eu(III) solvent extraction experiments, UV absorption spectrophotometry, NMR studies ESI-MS. Structures of 1 complexes Eu(III), Ce(III) the linear uranyl (UO22+) ion were obtained they...

Brain iron accumulation has been associated with inciting the generation of oxidative stress in a host chronic neurological diseases, including Parkinson's disease. Using catecholaminergic neurotoxin 6-hydroxydopamine to lesion cellular dopaminergic pathways as model disease culture, selection 1-hydroxypyridin-2-one (1,2-HOPO) metal chelators were synthesized and their neuroprotective properties compared 3-hydroxypyridin-4-one; deferiprone (3,4-HOPO; DFP). Protection against 6-OHDA insult by...

This article describes a convenient method for the synthesis of ONNO-type tetradentate 6,6'-bis(2-phenoxy)-2,2'-bipyridine (bipyridine bisphenolate, BpyBph) ligands and their platinum(II) complexes. The methodology includes 1,2,4-triazine precursors followed by transformation to functionalized pyridines Boger reaction. Two complementary routes employing 3,3'- 5,5'-bis-triazines allow modification central pyridine rings in different positions, which was exemplified introduction cyclopentene...

Abstract The synthesis and evaluation of three novel bis‐1,2,4‐triazine ligands containing five‐membered aliphatic rings are reported. Compared to the more hydrophobic 1 – 3 six‐membered rings, distribution ratios for relevant f ‐block metal ions were approximately one order magnitude lower in each case. Ligand 10 showed an efficient, selective rapid separation Am III Cm from nitric acid. speciation with trivalent was probed using NMR titrations competition experiments, time‐resolved laser...

The new ligand 6,6′′-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-1,2,4-benzotriazin-3-yl)-2,2′:6′,2′′-terpyridine (CyMe4-BTTP) has been synthesized in 4 steps from 2,2′:6′,2′′-terpyridine. Detailed NMR and mass spectrometry studies indicate that the forms 1 : 2 complexes with lanthanide(III) perchlorates where aliphatic rings are conformationally constrained whereas formed nitrates mobile. An optimized structure of solution complex Yb(III) was obtained relative magnitude induced paramagnetic...

The complexation and extraction of the adjacent minor actinides Am(III) Cm(III) by both hydrophobic hydrophilic pre-organized 2,9-bis(1,2,4-triazin-3-yl)-1,10-phenanthroline (BTPhen) ligands has been studied in detail. It shown that is extracted more rapidly than CyMe4–BTPhen ligand into different organic diluents under nonequilibrium conditions, leading to separation factors for Am over Cm (SFAm/Cm) as high 7.9. Furthermore, selectivity can be tuned through careful choice conditions...

Abstract The synthesis and extraction of americium(III) europium(III) from aqueous nitric acid solutions by the new BTBP ligands 6,6'-bis(5,5,7,7-tetramethyl-5,7-dihydrofuro[3,4-e]-1,2,4-triazin-3-yl)-2,2'-bipyridine (Cy5-O-Me4-BTBP), 6,6'-bis(5,5,7,7-tetramethyl-5,7-dihydrothieno[3,4-e]-1,2,4-triazin-3-yl)-2,2'-bipyridine (Cy5-S-Me4-BTBP) is described. affinity for Am(III) selectivity over Eu(III) Cy5-S-Me4-BTBP were generally higher than Cy5-O-Me4-BTBP. For both ligands, 3 M HNO3 into mM...

Abstract The novel hydrophilic back-extraction agent TS-BTPhen (3,3ʹ,3ʺ,3ʹʺ-[3-(1,10-phenanthroline-2,9-diyl)-1,2,4-triazine-5,5,6,6-tetrayl]tetrabenzenesulfonic acid) was tested for its selectivity towards Am(III) over Cm(III) and Eu(III) with a TODGA (N,N,Nʹ,Nʹ-tetraoctyldiglycolamide) based solvent. Batch experiments were carried out using dissolved in aqueous nitric acid solution tracers of 152 Eu, 241 Am 244 Cm. A significant increase the separation factor Cm from SF Cm/Am = 1.6 up to...

We have studied dissociative electron attachment (DEA) between low energy ($\ensuremath{\le}0.6\text{ }\text{ }\mathrm{eV}$) longitudinally polarized electrons and gas-phase chiral targets of 3-bromocamphor (${\mathrm{C}}_{10}{\mathrm{H}}_{15}\mathrm{BrO}$), 3-iodocamphor (${\mathrm{C}}_{10}{\mathrm{H}}_{15}\mathrm{IO}$), 10-iodocamphor. The DEA rate depends on the sign incident helicity for a given target handedness, it varies with both atomic number ($Z$) location heaviest atom in...

The kinetic separation effect was observed leading to a factor for Am(III) over Cm(III) as high 7.9 by using 2,9-bis-(1,2,4-triazin-3-yl)-1,10-phenantroline (BTPhen) ligands in our recent study. In an attempt explain the tendencies, several models were tested. A model based on mass transfer rate-controlling process found best describe data and allowed simulate dependence of Am/Cm time. calculated values overall mass-transfer coefficients confirmed that caused different rates extraction. This...