CARBAMOYLMETHYL SULFOXIDES AS NOVEL EXTRACTANTS FOR ACTINIDES

The present paper describes a novel type of extractant for actinides c alled bis(dioctylcarbamoylmethyl) sulfoxide which neither contains pho sphorus nor entails the addition of tributyl phosphate as phase modifi er for extraction. This extractant, abbreviated as CMSO, has been foun d to be freely soluble in dodecane and to form no third phase even wit h concentrations of nitric acid as high as 10M. The distribution ratio s for the extraction of Am(III), Pu(IV) and U(VI) at trace levels have been found to be 13, 220 and 11, respectively, from 5M nitric acid us ing 0.2M CMSO in dodecane and those for back-extraction have been foun d to be 2 x 10(-4), 8 x 10(-3) and 5 x 10(-2) using 0.01M nitric acid, 0.1M oxalic acid and 0.35M sodium carbonate, respectively. Similar di stribution ratios were obtained with the recycled extractant. Extracti on was found to be very rapid. Eu(III) and Sr(II), were found to be mo derately extracted with distribution ratios of 2 and 0.77, respectivel y, while the extraction of Cs(I) was negligible (K(D) = 0.005).