SEQUENTIAL AND RAPID-DETERMINATION OF PO-210, BI-210 AND PB-210 IN NATURAL-WATERS

A sequential and rapid separation method for the determination of rado n daughter nuclides, Pb-210, Bi-210 and Po-210 has been developed for application to natural waters. Rapid separation is attained by the use Of the same hydrochloric acid solution. After isolation of the three radionuclides from the sample by co-precipitation with added Fe3+, pol onium isotopes are first spontaneously deposited onto a silver disc fr om a 0.5N hydrochloric acid solution. Next, bismuth isotopes are elect rodeposited onto a platinum net cathode coupled with a platinum coil a node at 1.2 V. Finally, lead isotopes are electrodeposited onto a plat inum net cathode at 1.8 V from the remaining solution by adding hydrox ylamine hydrochloride as an anodic depolarizer. This method can be app lied to meteorological precipitation samples where these three nuclide s are separated within 10 hr after the sampling with chemical yields o f more than 80% for Po-210 and Bi-210 and more than 70% for Pb-210. Th is method is applicable to other environmental water samples.