Solvent Extraction of Inorganic Nitrates with Diphosphonate Ester. I. Zirconium, Yttrium and Lanthanide Nitrates

The extractability of Zr, Y, Ce, Pm, Eu, and Lu was studied on the system between tetra-n-butyl ethylenediphosphonate (TBEDP) -kerosene and various nitric acid concentrations. The results obtained are plotted with results for extraction with TBP from nitric acid for comparison. The distribution ratios, which can increase when other nitrates are added to nitric acid, suggest that the extraction of zirconium by TBEDP depends on the nitrate ion concentration to some extent. The results also indicate that zirconium is extracted more readily from nitric acid solution containing aluminum nitrate than from pure nitric acid solution of the same total nitrate ion concentration. (P.C.H.)