BIOSORPTION OF TC-99 AND SOME ACTINIDES BY BOTTOM SEDIMENTS OF LAKE-BELOE-KOSINO OF THE MOSCOW REGION

Sorption of technetium, plutonium, and curium by natural and sterilize d bottom sediments sampled from Lake Beloe Kosino of the Moscow region was studied. Natural bottom sediments sorb 98% of technetium within 4 .5 months. Technetium sorption is due to sulfate reduction process gen erating hydrogen sulfide, which converts initial readily soluble sodiu m pertechnetate to insoluble Tc(VII) and Tc(IV) sulfides. For actinide s the degree of sorption by natural and sterilized bottom sediments is 98 and 36%, respectively. The ratio between solid and liquid phases i n the bottom sediments was 2.3 x 10(-2) g ml(-1).