THE METHOD FOR DETERMINATION OF 241Am ACTIVITY IN CORAL SAMPLES

Abstract

    The method described here is used to determine 241Am activity in the Coral samples.The principles of the method are:- The sample is dissolved in a mixture of concentration HNO3 and HCl acid with theratio of 1: 3.- 241Am is co-precipitated in oxalate form, 243Am tracer is used to determineradiochemical separation recovery.- 241Am is separated from other isotopes by iron hydroxide precipitate, followed byanion DOWEX 18 resin in 8N HNO3 and 10N HCl solution respectively; and finally,241Am is absorbed on DOWEX 14 resin in (1N HNO3 + CH3OH 93%) solution; elute241Am by (1.5N HCl + 86% CH3OH) solution.- 241Am is deposited on stainless steel plate by using electrodeposition technique in0.3 M Na2SO4 solution for 1 hour at 1.2 A, and then measuring on alpha spectrometerwith a twin energy peaks of 5.49 MeV (84.5%) and 5.44 MeV (13.2%) with the modestcounting period about 200,000 s - 300,000 s.The chemical recovery about 65% and detection limit about 0.0004 Bq/kg. Sometypical results on the 241Am activity in Coral samples affirm the possibility as well asthe accuracy of the method.

Key words: 241Am, Coral sample.