Solvent extraction of lanthanide ions with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 (HPMBP), III: Extraction of gadolinium(III), terbium(III), dysprosium(III), holimum(III), and thulium(III) byHPMBP from aqueous solutions

Abstract

The solvent extraction behaviour of Gd(III), Tb(III), Dy(III), Ho(III), and Tm(III) has been investigated using 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 (HPMBP or HL) in carbon tetrachloride as the extractant. Depending on the concentration ofHPMBP in the organic phase the chelatesLnL3 [Ln(III)=Gd, Tb, Dy, Ho, Tm] and adductsLnL3 · HL [Ln(III)=Gd, Tb, Dy, Ho] were extracted. The extraction equilibrium constants (Kex3 orKex4) for the formation ofLnL3 orLnL3 · HL and the two-phase stability constants of the chelates or adducts (β 3 x , β 4 x ) have been evaluated.