SYNERGIC EXTRACTION(VI) FROM DIFFERENT AQUEOUS-MEDIA USING HTTA AND NEUTRAL DONORS

The extraction of uranyl ion from aqueous nitrate, perchlorate and thi ocyanate medium with 2-thenoyl trifluoroacetone (HTTA) and N,N-disecbu tyl pentanamide (DBPA) has been studied to know the extracted U(VI) sp ecies. It is established that the U(VI) species responsible for synerg ism is UO2(TTA)2.DBPA when aqueous medium is nitric acid. With aqueous thiocyanate medium, the predominant U(VI) species extracted is UO2(NC S) (TTA).2DBPA. The synergic extraction of U(VI) from aqueous perchlor ate medium using HTTA in combination with a bifunctional neutral organ ophosphorus extractant, DBDECMP has also been studied. The U(VI) speci es responsible for the synergism is found to be UO2(TTA)2.DBDECMP. Equ ilibrium constant values for the various extraction equilibria involve d are calculated.