Comparative studies on Y(III) and Dy(III) extraction from hydrochloric and nitric acids by Cyanex 572 as a novel extractant

Extraction of Y(III) and Dy(III) from hydrochloric and nitric acids by Cy-572 in kerosene was studied. The factors affecting the extraction were separately investigated. The stoichiometry of the extracted species was deduced on the basis of slope analysis method. Evaluation of extraction equilibrium and stripping investigation was studied as well as saponification effect of Cy-572. The composition of the extracted metal species in the organic phase was found to be $\overline{{[\text{MA}}_3·{\left(\text{HA}\right)}_3]}$ for Y(III) or Dy(III) in both media. 1.0 mol/L HCl is the best stripping agent for each metal ion from the studied acidic media in one step. Saponified Cy-572 does not exhibit any selectivity towards the extraction of Y(III) or Dy(III) from both HCl and HNO₃ solutions. Based on the obtained results, the data were compared and the separation feasibility between lanthanides and Y(III) in the two media was discussed.