A Mechanism of Desorption of Pertechnetate Ions from Macroporous Vinyl Pyridinium Anion-Exchange Resin Using Tributyl Phosphate

Abstract

Based on kinetic studies, a mechanism for the elution of technetium from an anion-exchanger in the form of an extractable complex with tributyl phosphate (TBP) has been suggested for the purpose of improving the ion exchange technology of the technetium extraction by elution of technetium-99 from VP-1AP anion exchange resin with a TBP solution. The effect of diluents and extraction reagents on the quantitative desorption of pertechnetate has been studied. It has been found that the process of desorption of pertechnetate ions from the VP-1AP anion-exchanger can be described by equations characteristic of the film kinetics of elution, which is caused by the presence of an additional stage of transfer of the substance across the phase interface from the phase of an aqueous solution associated with anion-exchanger to the phase of organic extracting eluent. Based on the conducted studies, the possibility of improving the existing sorption technology of technetium isolation has been demonstrated.