Separation of Rare Earth Elements from Base Metals in Concentrated HNO₃, H₂SO₄ and HCl Solutions with Diglycolamide

Abstract

The separation of Nd(III) and Dy(III) from Fe(III) and Ni(II) in relatively high concentrations of HNO 3 , HCl and H 2 SO 4 solutions (0.1 -7 M) was investigated using

Extraction Chromatographic Materials for Clean Hydrometallurgical Separation of Rare-Earth Elements Using Diglycolamide Extractants

“…This has been shown in the literature for extraction of REE from nitric acid, 31,32 and is also true from HCl and H 2 SO 4 media. 33,34 We show a direct comparison under the same conditions (0.1 M DGA in a modified isoparaffinic kerosene) in Figure 2 for REE extraction from 3 M HCl. In this system, DMDODGA shows superior extraction, 10 to 15-fold higher, than by the TODGA for all lanthanides.…”

A triple tandem columns extraction chromatography method for isolation of highly purified neodymium prior to 143Nd/144Nd and 142Nd/144Nd isotope ratios determinations

“…This medium allows the extraction of the LREE by the subsequent DGA resin, for a further separation stage of Ce and Pr left in the Nd cut. The diglycolamide ligands 48,49 form tridentate chelates with lanthanides, with the heavier Ln(III) complexes being more stable than the lighter Ln(III) ones 50 . This is reflected by an increasing extraction trend from La to Lu similar to that displayed by alkyl phosphorus acids, but through a different mechanism in which the extraction into the organic phase is favoured by high concentration of anion (NO 3 or Cl -).…”

Hidden Nature of the Conversion Reaction from Rare Earth Chloride to Oxychloride and the Application to Novel Separation

“…To compare the result with that of current study of solvent reactions, we referred to the study reported by Narita et al In that study, after equal molar amounts of Nd and Dy were extracted by 1 M of HNO 3 , Nd was experimentally back‐extracted into an organic phase. In this case, Nd was concentrated into the organic phase, and Dy remained in the water phase.…”