Tributyl phosphate-carbon tetrachloride extraction

Table IV. 0.18M Tributyl Phosphate—Carbon Tetrachloride Extraction of Cerium and Berkelium from Nitric Acid Solutions...

Recuplex A variant of the Puiex process for extracting plutonium, in which the tributyl phosphate is dissolved in carbon tetrachloride in order to make the organic phase denser than the aqueous phase. 

We took advantage of the property of different solvents to extract selectively the tetravalent actinide and lanthanide elements. Some of them are sufficiently stable in the presence of oxidizing agents. Among the organonitrogen and organophosphorus compounds we used were tri-laurylmethylammonium (TLMA) salts and tributyl phosphate (TBP) in carbon tetrachloride. 

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