JOURNAL ARTICLE

BTP-based ligands and their complexes with Eu(3+) at "oil"/water interfaces. A molecular dynamics study

G Benay, R Schurhammer, G Wipff
Physical Chemistry Chemical Physics: PCCP 2010 September 28, 12 (36): 11089-102
20676417
Heterocyclic N-donor ligands based on the bistriazinylpyridine (BTPs) skeleton have been recently developed to separate trivalent actinides from lanthanides by liquid-liquid extraction from nuclear solutions. In this paper, we report molecular dynamics investigations on BTPs in water-"oil" biphasic systems (oil = hexane + octanol vs. hexane vs. nitrobenzene vs. chloroform) and compare different BTP derivatives, their neutral vs. protonated forms, and their 1 : 3 complexes with Eu((III)). Neutral BTPs are found to be weakly surface active and to display multiple orientations at the interface, depending on time and on their lateral and para substituents. This contrasts with their protonated forms that strongly adsorb at interfaces with neutral or acidic water. Remarkably, the protonated cyMe(4)-BTPH(+) and, to a lesser extent, (i)PrBTPH(+) ligands adopts at the interface an "inversed orientation", where NH(+) points towards oil, instead of water. The [Eu(BTP)(3)](3+) complexes are also found to be highly surface active: in spite of Eu((III)) shielding by the three ligands, these complexes remain strongly attracted by water at the aqueous side of the interface. Taken together, the MD results suggest that ion complexation by BTPs occurs right at the interface, from the protonated BTPH(+) forms. They may explain why extraction is improved upon increase of the aqueous phase acidity, though with slow kinetics. They also open perspectives for designing new derivatives for efficient separation of trivalent actinides from lanthanides.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read
20676417
×

Save your favorite articles in one place with a free QxMD account.

×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"