Solvent extraction of U(VI) by N,N-dimethyl-N′,N′-dioctylsuccinylamide and N,N-dimethyl-N′,N′-didecylsuccinylamide in cyclohexane

The extraction of uranyl nitrate by novel extractants of N,N-dimethyl-N′,N′-dioctylsuccinylamide (DMDOSA) and N,N-dimethyl-N′,N′-didecylsuccinylamide (DMDDSA) from aqueous nitric/nitrate solutions was investigated. It was found both the concentration of HNO3 and extractants had an effect on the U(VI) extraction distribution. The extraction mechanism was established, and stoichiometry of the main extracted species was confirmed to be UO2(NO3)2·2DMDOSA and UO2(NO3)2·2DMDDSA, respectively. Both of the extraction reactions are exothermic. FTIR spectral study of the U(VI) extracted species was also made.