Comprehensive extraction study using N,N-dioctyldiglycolamic acid.
We report on the acid dissociation constants (Ka) of diglycolamic acid-type ligands together with comprehensive data on the extraction performance of N,N-dioctyldiglycolamic acid (DODGAA) for 54 metal ions. The pKa of the diglycolamic acid framework was determined to be 3.54 ± 0.03 in water (0.1 M LiCl, 25°C) by potentiometric titration, indicating that DODGAA is strongly acidic compared with acetic acid. DODGAA can quantitatively transfer various metal ions among the 54 metal ions through a proton-exchange reaction, and provides excellent extraction performance and separation ability for rare-earth metal ions, In(III), Fe(III), Hg(II), and Pb(II) among the 54 metal ions.
Division of Chemistry for Nuclear Engineering, Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency (JAEA).
Kojiro
K
Shimojo
Ayaka
A
Nakai
Hiroyuki
H
Okamura
Takumi
T
Saito
Akira
A
Ohashi
Hirochika
H
Naganawa