Local structure and distribution of remaining elements inside extraction chromatography adsorbents

A new adsorbent of the extraction chromatography technology impregnating CMPO and HDEHP extractants for minor actinide recovery process was prepared and fundamental performance were evaluated by batch-wise adsorption/elution experiments, EXAFS analysis and PIXE-CT analysis. Selective minor actinides recovery from the adsorbent charging minor actinides and lanthanides was revealed to be possible owing to synergistic extraction of lanthanides by CMPO and HDEHP. Discharging the residual lanthanides is essential for repeated use of the adsorbent, and ammonium acetate solution was proposed as an appropriate eluent although the elution ratio is not large enough. In order to enhance the elution performance of the lanthanides, improvements in structure of the adsorbent as well as in the eluent were shown to be important.