Solvent Extraction of Lanthanides(III) with N‐p‐Phenylbenzoyl‐N‐phenylhydroxylamine

Abstract

N‐p‐Phenylbenzoyl‐N‐phenylhydroxylamine (phenyl‐BPHA) was newly synthesized. The acid‐dissociation constant and distribution constant between chloroform and 0.1 mol dm−3 potassium chloride solution of phenyl‐BPHA were spectrophotometrically determined. The solvent extraction of lanthanides(III) (Ln) with phenyl‐BPHA was investigated. The representative lanthanides (Yb, Ho, Eu, Pr, and La) were all found to extract with compounds as self‐adducts of the form, LnL3(HL)2, where L and HL denote the ligand anion and neutral ligand, respectively. The extraction constant and separation factor were compared with those of the other derivatives of N‐benzoyl‐N phenylhydroxylamine (BPHA) previously reported. As the results, it was found that the separation factors for lanthanides(III) pairs represented by Pr/Eu, Eu/Yb, and Pr/Yb, with phenyl‐BPHA have moderate values by the comparison of those of other hydroxamic acids and other extractants.