Complex formation reactions of certain lanthanides(III) with 5,7-dibromo-8-hydroxyquinoline in two-phase system in the presence of a modifying agent

The influence of methanol as a modifier of the Ln(III) (where Ln = La, Nd, Eu, Gd) extraction process with solutions of 5,7-dibromo-8-hydroxyquinoline (Hdbq) in chloroform was examined. It was stated that the presence of methanol in the polar phase evokes a synergistic effect. It is connected with the formation of Ln(dbq)3(CH3OH)3 mixed ligand adducts in organic phase. The parameters of the extraction process were determined and the separation factors of Nd(III), Eu(III), Gd(III) from La(III) were calculated. (authors)