Efficiency of Radiocaesium Concentration from Large Volume Natural Water Samples by Scavenging with Ammonium Molybdophosphate

A method for the non-radioactive determination of the recovery of radiocaesium when concentrated from large volume natural water samples is described. The caesium scavenging efficiency of ammonium molybdophosphate (AMP) was estimated from the ratio of stable caesium added as a carrier (and becoming now an internal yield tracer) and recovered with the precipitate. Stable caesium was determined by using flame emission spectrometry. Results showed that the scavenging efficiency ranged from 91 3% to 106 ± 5% with a mean value of 98±4% and therefore the scavenging procedure may be considered quantitative. Further experiences showed that the contact time could be reduced to less than five minutes and that the proportion of reagent used in our concentration method was within the appropriate rnge. © 1993, Walter de Gruyter. All rights reserved.