Extraction of lanthanoids(III) with di-isodecyl phosphoric acid from nitric acid solution

The extraction of Nd(III) with di-isodecylphosphoric acid was studied and compared with that by di(2-ethylhexyl)phosphoric acid. DIDPA possesses higher D sub(f) values in a strong acid medium but poorer separation factors against lanthanoids (III) than that of DEHPA. Mono(2-ethylhexyl)phosphoric acid increased extraction of Nd(III) with DIDPA in a similar manner as in the case of DEHPA, by a factor of D sub(f) of 103. The extraction of Sr(II) was also investigated with DIDPA, which showed a maximum of D sub(f) at pH 5.0. Results showed that DIDPA is a promising extractant for the partitioning of the high level liquid waste. (auth.)