Separation of Rare Earth Elements (REE) by Ion Interaction Chromatography (IIC) Using Diglycolic Acid (ODA) as a Complexing Agent

Autor: Krzysztof Kulisa, Rajmund Dybczyński
Rok vydání: 2021
Předmět:
Zdroj: Chromatographia. 84:473-482
ISSN: 1612-1112
0009-5893
DOI: 10.1007/s10337-021-04025-y
Popis: The possibility of rare earth elements (REE) separation by ion interaction chromatography (IIC) employing their complexes with diglycolic acid (ODA) in anion exchange mode has been studied theoretically and experimentally. Calculations, assuming that only trivalent complex is significantly uptaken by the stationary phase, indicated that at at pH 4–6, the retention in the lanthanide series should increase from La to the Tb–Dy–Ho region with yttrium showing apparent atomic number (App.At.No.) of 67½ and then decrease with further increase of atomic number. Chromatographic experiments in the system: Column: Eternity C18—mobile phase 5 mM ODA/8.6 mM TBAOH/0.6 mM HNO3; pH 4.60 confirmed theoretically predictions. It was found that scandium at pH ≥ 4.0 elutes in front of the whole REE group but at low pH enters the region of light lanthanides. The non-monotonical change of affinity of the REE with the increase of atomic number results in quite unusual order of elution of REE namely: Sc
Databáze: OpenAIRE