On Acidic Organodiphosphorus Extractants. Part V. Extraction Dependency of Trivalent Europium on the Dielectric Constant of the Organic Phase

Abstract

The extraction of Eu(III) has been carried out from a 1 M (H,Na)Clo₄ solution into different organic solvents at constant total concentration (6.67 × 10^?3 M) of the extractant, di-n-butyl-ethane-(l,2)-diphosphonic acid (H₂B₂-EDP). The distribution coefficient of Eu(III) is influenced quite appreciably by the nature of the organic solvent. We observe that the distribution coefficient can vary by a factor of 10⁶ for two solvents such as chloroform and ieo-octane. The experimental results are compared with those of Dréze¹, who used di-n-butyl-phosphoric acid (HDBP) for the extraction of Eu(lII) into different organic solvents. If we assume that H₂-B₂-EDP remains monomer for a total concentration of 6.67 × 10^?3 M in the solvents used², then we may conclude that the extraction of Eu(III) by the associated HDBP or the monomer H₂B₂EDP is influenced in the same manner in the solvents used.