SOLVENT EXTRACTION OF SOME METALS BY MIXTURES OF TRIBUTYL PHOSPHATE WITH ALKYLAMMONIUM NITRATES

The distribution of cerium(III), zirconium(IV), and plutonium(IV) was studied in systems where 3M nitric acid was the aqueous phase and a solution of tributyl phosphate and trilaurylammonium or trilaurylmethylammonium nitrates in n-hexane or toluene was the organic phase. A synergic effect was observed in the extraction of cerium(III) and zirconium(IV); it was explained by the formation of mixed metal nitrate-tributyl phosphate-alkylammonium nitrate complexes. No significant mixed complex formation is assumed in the extraction of plutonium(IV) where an antagonistic effects was observed in most cases. The effect was ascribed to the lowering of the activity coefficients of the alkylammonium nitrate extracting species in the presence of tributyl phosphate. © 1969.