Determination of successive complexation constants in an ionic liquid: complexation of UO(2)(2+) with NO(3)(-) in C(4)-mimTf(2)N studied by UV-Vis spectroscopy.
The complexation of UO(2)(2+) with NO(3)(-) has been investigated in the ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide by UV-vis spectroscopy at T = 18.5 degrees C. The complexation is evidenced through the appearance of four peaks at 425, 438, 453, and 467 nm. EXAFS data indicate that the trinitrato complex, UO(2)(NO(3))(3)(-), is dominating the speciation for a reagent ratio of [NO(3)(-)]/[UO(2)(2+)] > 3. Assuming three successive complexation steps, the conditional stability constants are calculated, the individual absorption spectra are derived, and a speciation plot is presented.
Georg
Sylvia
S
IPHC, UMR 7178 CNRS-IN2P3 et Université de Strasbourg, 23 rue du Loess, 67037 Strasbourg cedex 2, France.
Billard
Isabelle
I
Ouadi
Ali
A
Gaillard
Clotilde
C
Petitjean
Laetitia
L
Picquet
Michel
M
Solov'ev
Vitaly
V