LAUSR

Abstract Extraction behavior of Eu(III) from nitric acid medium was studied in a binary solution of tetra bis(2-ethylhexyl)diglycolamide (TEHDGA) and an acidic extractant (HA) present in n -dodecane ( n -DD). The acidic extractants chosen were bis(2-ethylhexyl)phosphoric acid (HDEHP), bis(2-ethylhexyl)phosphonic acid (PC88A) and bis(2,4,4-trimethylpentyl)phosphinic acid (CYANEX-272) whose pK a values were 3.24, 4.51 and 6.37 respectively. The interaction of Eu(III) with TEHDGA and HA at various acidities was studied by Attenuated Total Reflectance (ATR)-Fourier Transform Infrared (FTIR) spectroscopy. The changes in the amidic C O and etheric C O stretching bands of TEHDGA and phosphoryl P O stretching bands of HA occurred upon Eu(III) extraction at various acidities were monitored, and correlated the peak shifts observed in the ATR-FTIR spectrum to the distribution ratio of Eu(III) in the binary solution and pK a value of the acidic extractant.