Behavior of a synergistic system in the extraction of Pr(III) from chloride medium using di-2-ethylhexyl phosphoric acid and 2-ethylhexylphosphonic mono-2-ethylhexyl ester

• Published in: Separation science and technology Vol. 52; no. 6; pp. 1015 - 1021
• Main Authors: Zhang, Fengyun, Wang, Amin, Zhou, Fengmin, Dai, Jingjie, Wu, Wenyuan
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 13.04.2017; Taylor & Francis Ltd
• Subjects: Cation exchanging; Cations; Chlorides; Composition; Diethylhexylphosphoric acid; Esters; Extractants; Infrared radiation; Infrared spectroscopy; Kerosene; Mathematical analysis; P204; P507; Phosphoric acid; rare earths; Solvent extraction; Stoichiometry; synergistic extraction
• ISSN: 0149-6395; 1520-5754
• DOI: 10.1080/01496395.2017.1281301

This paper will investigate the synergistic solvent extraction of extracted Pr from a chloride medium, using a mixture of two acidic extractants, namely 2-ethylhexylphosphonic mono-2-ethylhexyl ester (P507, HA) and di-2-ethylhexyl phosphoric acid (P204, HB) in kerosene. The stoichiometry of the extracted species was characterized by a classical lg-lg plot analysis. The composition of the extracted complexes has been determined as Pr(HA 2 )(HB 2 ) 2 . Moreover, the differences of the extraction behavior from sulfuric and chloride medium were discussed in detail. The values of equilibrium constant and thermodynamic parameters such as △G, △H, and △S were also calculated. A cation-exchange mechanism was proposed and further clarified by slope analysis and IR spectra.