Isotope separation of gadolinium with strong cation exchange resin using displacement chromatography

Naturally occurring gadolinium consists of 7 stable isotopes. ¹⁵²Gd, ¹⁵⁴Gd, ¹⁵⁵Gd, ¹⁵⁶Gd, ¹⁵⁷Gd, ¹⁵⁸Gd and ¹⁶⁰Gd of which abundance ratios are 0.20, 2.18, 14.80, 20.47, 15.65, 24.84 and 21.86 at %, respectively. Gadolinium has the highest cross section for the capture of thermal neutrons compared to other elements. Further, ¹⁵⁷Gd and ¹⁵⁵Gd have higher neutron absorption cross sections (254000 and 60900 barns, respectively) compared to the other isotopes of Gd. Natural gadolinium is currently used as a burnable poison in nuclear fuel but the use of isotopically enriched ^155/157Gd would make it an effective burnable poison. The chemical exchange isotope separations are inherently equilibrium processes and therefore they are considered as the energy conservation processes. Separation of isotopes by ion exchange chromatography is one of the most effective chemical exchange methods, which is based on the chemical equilibrium between isotopic species distributed between the stationary resin phase and the mobile solution phase. In the present study we have performed separation of gadolinium isotopes using displacement chromatography