ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Effect of crown ethers on the solvent extraction and separation of lanthanide(III) ions with 4-benzoyl-3-methyl-1-phenyl-2-pyrazolin-5-one

Maria A. Petrova and Ivan L. Dukov

Department of Inorganic Chemistry, University of Chemical Technology and Metallurgy, 8 Kl. Okhridski, 1756 Sofia, Bulgaria

E-mail: idukov@abv.bg

Received: 26 June 2007  Revised: 9 August 2007  Accepted: 13 August 2007

Abstract: Synergistic solvent extraction of 14 lanthanides with mixtures of 4-benzoyl-3-methyl-1-phenyl-2-pyrazolin-5-one (HP) and the crown ethers (S), 18-crown-6, benzo-18-crown-6 or dibenzo-18-crown-6 from an aqueous chloride medium with the constant ionic strength of 0.1 mol dm⁻³ was investigated using benzene as a diluent. The composition of the species extracted was determined as LnP3 · S. The addition of a crown ether to the chelating extractant produced rather significant synergistic effects. On basis of experimental data, values of equilibrium constants, synergistic coefficients, and separation factors were calculated.

Keywords: synergistic extraction - lanthanides - 4-benzoyl-3-methyl-1-phenyl-2-pyrazolin-5-one - 18-crown-6 - benzo-18-crown-6 - dibenzo-18-crown-6 ethers

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-008-0012-4

Chemical Papers 62 (2) 207–214 (2008)