The development of a sequential method for the determination of actinides and 90Sr in power station effluent using extraction chromatography

Determination of the actinides and 90Sr in power station effluent requires their radiochemical isolation prior to measurement. Historically, techniques such as precipitation, ion exchange and solvent extraction have been used but these methods can be complex, time consuming and produce large amounts of chemical waste. A more environmental friendly sequential scheme for their determination in power station effluent using extraction chromatography has been developed. This is a simplified method which minimises chemical waste and makes use of commercially available pre-packed chromatography columns. An Eichrom TRU·Spec® column was used for the separation of isotopes of plutonium from americium and curium followed in sequence by an Eichrom Sr·Spec® column for the separation of 90Sr. The isolated actinides were prepared for alpha spectrometry analysis by electrodeposition and 90Sr was analysed by liquid-scintillation counting. The tracers 242Pu, 243Am and 85Sr were used to measure chemical yields. Method evaluation was carried out on water samples spiked with certified radionuclide standards to determine precision, accuracy, detection limits and chemical recoveries. Finally, testing and evaluation of the method was carried out on power station effluent.