Neodymium isotope separation experiment based on the ligand complex formation was carried out with a cyclic displacement chromatography system which is composed of three glass columns, 0.8 cm I.D. × 100 cm long, with water jacket, connected in series with Teflon tubes, 1 mm inner diameter, so that they were repeatedly used in merry-go-round way for the desired migration length. The set of apparatus for the chromatographic experiment is illustrated in Fig. 1, while the experimental conditions are summarized in Table 1.