Influence of lactic acid on the solvent extraction separation of Sm(III) and Co(II) from chloride medium using DEHPA

A novel process for the separation of Sm (III) and Co (II) from chloride medium using lactic acid in the aqueous feed employing Di-2-ethylhexyl phosphoric acid (DEHPA) in petrofin as organic phase solvent has been developed. Complete separation has been accomplished with 1 M HLac and 0.1 M DEHPA in the pH range 1?3 and using 2.2 M HLac at pH 3 with 0.2 M DEHPA. Sm (III) could be entirely stripped off the loaded organic solvent by means of 1.2 M HCl and HNO3. The extraction process is heat releasing for Sm (III) and heat absorbing for Co (II).