AN INVESTIGATION OF THE TRANSFER OF URANYL NITRATE ACROSS THE WATER—TRIBUTYL PHOSPHATE INTERFACE BY THE METHOD OF PHOTOGRAPHIC PHOTOMETRY

摘要

The resistance of the water—tributyl phosphate (TBP) interface to diffusion of uranyl nitrate was investigated by a photographic photo-metric technique. The resistance was below the limit of detectability in the experiments, even with a surface-active agent present in the system. The sensitivity of the experiments established an upper bound for the interfacial resistance to diffusion equivalent to that of a 25-|i film of TBP under steady-state diffusion. The results indicated that the rate-limiting step in solvent extraction of uranyl nitrate from water by TBP is transfer of the diffusing species between the interface and the bulk phase rather than across the interface.