| 摘要 |
<p>An aqueous metal soln. is mixed with an immiscible solvent for extracting at least one metal. The solvent and aqueous phases are separated, and the aquasol is mixed with a second immiscible solvent to repeat the process for a different metal. Sequential mixing of different solvents and phase separation is repeated until the required degree of metal concentration in the solvent soln. is obtained. The metals are then isolated from their solvents. More spec., the process is for separating rare earth metals, particularly Pr, Nd and Sm from Dy and Y, whereby Gd is retained in the aqueous phase from which it is separated by evaporation. A suitable solvent is an alkyl amine, pref. a mixture of tertiary alkyl (primary) amine with 18-21 C-atoms, with an alkyl phosphate, pref. di-2-ethyl hexyl phosphoric acid.</p> |
