STUDY ON THE EXTRACTION OF U(IV) RELEVANT TO PUREX PROCESS

Extraction of U(IV) by an organic phase containing 30% tri-n-butyl pho sphate (TBP) in dodecane from aqueous nitric acid solution containing large amount of U(VI), relevant to nuclear fuel reprocessing by PUREX process, was studied. While acquiring distribution data, an argon atmo sphere was maintained. A potentiometric method was used for the determ ination of U(IV) in the two phases after equilibration. Hydrazine used as stabiliser of U(IV) in the stock solution was destroyed and sulpha mic acid was added just before equilibration to avoid the interference due to hydrazine in the subsequent determination of U(IV). Uranium(IV ) distribution data between 30% TBP in dodecane and aqueous solution o f uranium(VI) and nitric acid of varying concentrations have been pres ented and compared with available literature data.