A NOVEL TECHNIQUE FOR THE SIMULTANEOUS DETERMINATION OF PB-210 AND PO-210 USING A CROWN-ETHER

A simple radiochemical procedure has been developed to separate lead a nd polonium simultaneously from different environmental and biological materials. After adding Po-208 tracer and lead carrier samples are de composed using mineral acids. Lead and polonium are selectively retain ed from 2 M HCl solution by the bis-4,4'(5')-t-butyl-cyclohexano-18-cr own-6-ether; polonium is stripped with 6 M HNO3 while lead is stripped with 6 M HCL solution. A polonium source is prepared by spontaneous d eposition onto a silver disk. The activity concentration of Po-210 is determined by isotope dilution alpha spectrometry. Lead is precipitate d as oxalate; the chemical recovery is determined by gravimetry. The a ctivity concentration of Pb-210 is calculated from the liquid scintill ation spectrum. (C) 1997 Published by Elsevier Science Ltd.