Pavel N. Nesterenko and Phil Jones
The possibility was demonstrated of the isocratic separation of 14 lanthanides and yttrium using a chromatographic column packed with iminodiacetic acid bonded to silica and with diluted nitric acid solutions in the presence of potassium nitrate as the eluent. The influence of concentration of nitric acid, ionic strength of the eluent and temperature was investigated. It was shown that in the presence of 0.5–1.0 M potassium nitrate the retention of the lanthanides is defined by the stability of the corresponding surface complexes with iminodiacetic acid functional groups. However, the presence of residual ion-exchange activity is still responsible for the selectivity of the separation of yttrium and Eu–Gd and Dy–Ho pairs.