Effect of the quaternary ammonium salt Aliquat 336 on the solvent extraction of lanthanoid (III) ions with thenoyltrifluoroacetone

The synergistic solvent extraction of 13 lanthanoids with mixtures of thenoyltrifluoroacetone (HTTA) and the quaternary ammonium salt Aliquat 336 in chloride (QCl) or perchlorate (QClO4) forms in C6H6 has been studied. The composition of the extracted species was determined as Q+[Ln(TTA)4]− (Q+ is a quaternary ammonium cation). The values of the equilibrium constant and the separation factor were calculated. The effect of the synergistic agent (QCl or QClO4) on the extraction process has been discussed. Additionally, the values of the equilibrium constant have been used to examine the tetrad effect.