Elution profiles of lanthanides with α-hydroxyisobutyric acid by ion exchange chromatography using fine resin.

Experiments were carried out using a strong acid cation exchange resin with a particle size of 75-150 μm, termed as "fine resin" in hydrogen ion form for the elution of individual lanthanides Sm, Eu, Gd, Tb, and Dy that are produced as fission products in the spent nuclear fuel and generated in the effluent during reprocessing of spent nuclear fuel. Batch experiments were carried out to study the effect of concentration of nitric acid on distribution coefficient. The distribution coefficient values for these individual lanthanides were determined in nitric acid medium in the concentration range of 0.01-4.0 N. Uptake of each individual lanthanide by resin was increased with increased nitric acid concentration from 0.01 to 0.5 N and remained similar from 0.5 to 1.0 N and decreased thereafter up to 4.0 N. Column experiments were also carried out using the same resin to study the parameters like pH of the eluent, flow rate, and resin bed height under isocratic elution conditions for eluting lanthanide elements using α-hydroxyisobutyric acid as eluent. The results of this study have indicated the possibility for the elution of individual lanthanides.