Authors:C. Bouvier, G. Cote, A. Sobczynska, M. Bogacki, and J. Szymanowski
Interfacial tension isotherms were determined and interpreted for ACORGA CLX-50. The hydration of extractant molecules in
aqueous solution and at hydrocarbon/water interfaces was studied by molecular modelling. The usefulness of this technique
to interpret the adsorption behavior was demonstrated. The interfacial kinetics was considered and relationships for various
models of interfacial mechanism were derived and discussed. Despite its high hydrophobicity, ACORGA CLX 50 strongly adsorbs
at the hydrocarbon/water interfaces and thus decreases effectively the interfacial tension. This high interfacial activity
of ACORGA CLX 50 can be explained by the formation of hydrates. The interfacial tension isotherm can be well matched with
the Szyszkowski equation. Molecular modelling suggests that ACORGA CLX 50 adsorbs at the hydrocarbon/water interface probably
as a tetrahydrate containing two water molecules bonded to the same carbonyl oxygen atom (e.g., at position 3), one water
molecule bonded to the oxygen atom of the second alkoxyl group (i.e., at position 5 when the hydration of carbonyl oxygen
at position 3 is previously considered) and, finally, one water molecule bonded with the pyridine nitrogen atom. Positions
3 and 5 are equivalent. It is also shown that when the extraction of copper takes place in the kinetic regime, the reaction
order with respect to ACORGA CLX 50 can change depending on the limiting step and the range of extractant concentration considered.
Thus, a decrease of the extractant concentration from 10−5M to 3·10−3M causes a fall of the order with respect to ACORGA CLX 50 from 1 to 0 and 2 to 1 when the formation of the intermediate 1∶1
and final 2∶1 complexes are considered to be the limiting step, respectively.
Authors:C. Bouvier-Capely, A. Manoury, A. Legrand, J. Bonthonneau, F. Cuenot, and F. Rebière
In this work the applicability of calixarene columns for actinides analysis in urine samples and drinking water was investigated.
A radiochemical procedure has been developed for U, Pu, Am analysis in urine. A simple and effective method has also been
proposed on a specific column named AQUALIX, for the separation and preconcentration of U from drinking water. These procedures
are suitable for routine analysis and require a considerably reduced number of steps of sample treatment as compared to current