Abstract:
Reactor irradiation of enriched
146Nd targets represents an important route for the production of
147Pm, where the major challenge lies in the efficient separation of trace
147Pm from a bulk Nd matrix. To establish a feasible separation process of
147Pm/Nd, the adsorption and separation behaviors of Nd and
147Pm on AG 50W×8 strong-acid cation-exchange resin were systematically investigated. Samarium was employed as a chemical surrogate for
147Pm during the optimization of process parameters.Batch adsorption results demonstrated that, in dilute hydrochloric acid media (
0.0001-0.1 mol/L HCl), Nd and
147Pm reached adsorption equilibrium within 10 min. The adsorption kinetics followed a pseudo-second-order model, and the adsorption isotherms were well described by the Langmuir model. The maximum adsorption capacities of the resin for Nd(Ⅲ) and Sm(Ⅲ) were determined to be 236.9 mg/g和210.9 mg/g, respectively, from which the adsorption capacity of
147Pm can be reasonably inferred to lie between those of Nd and Sm. Based on the batch adsorption results, systematic column separation studies were carried out using Sm as a surrogate for
147Pm. The optimal chromatographic conditions were determined to be 0.4 mol/L α-hydroxyisobutyric acid (α-HIBA) as the eluent at pH 4.1, a flow rate of 1.0 BV/h, and a temperature of 75 ℃. Under these conditions, separation experiments using
147Pm as a tracer demonstrated that
147Pm was preferentially eluted prior to Nd, achieving a resolution of 1.21 and a recovery yield exceeding 88.1%.This study establishes a cation-exchange chromatographic process coupled with complexing elution for the separation of
147Pm from Nd, providing a practical experimental basis for the purification of
147Pm from irradiated
146Nd targets.