Effect of a Tertiary Amine on the Synergic Extraction of Lanthanides by Thenoyltrifluoroacetone (HTTA)

Abstract

Synergie extraction of Yb(III) and Lu(III) has been carried out with thenoyltrifluoroacetone (HTTA) and tribenzylamine (TBA) in Chloroform from aqueous Perchlorate media from pH 1 to 6. The results demonstrate antisynergic effect from pH 3 to 6 in the extraction of Lu(III). The stoichiometric composition at pH 3 was established to be M(TTA)3 • 3TBA, where M = Yb(III) and Lu(III). However, the composition of synergic adducts at pH 6 was Yb(TTa)3 • 3TBA and Lu(TTA)3 • TBA. The change in the coordination number of the synergic adduct of Lu(III) at different pHs was further investigated through thermodynamic functions like enthalpy, entropy and Gibbs free energy. The mechanism of synergism and antisynergism of the synergic adducts at pH 3 and 6 has been discussed. The formation and stability constants have been determined.

Synergic Extraction of Eu(III) with 3-Methyl-1 -phenyl-4-trifluoroacetyl-2-pyrazolin-5-one (HPMTFP) and Tribenzylamine (TBA) from Perchlorate Media

“…In our previous studies [10][11][12][13], tribenzylamine (TBA) as neutral donor with Thenoyltrifluoroacetone (ΗΤΤΑ), a /?-diketone, an acidic chelating agent for the extraction of rare earths has been investigated. Although some phosphine oxides as neutral donors along with HPMTFP for the extraction of rare earths [14] and essential toxic elements [15] have been reported but synergic extraction system comprising HPMTFP and TBA has not been reported yet, for the extraction of rare earth elements.…”