[Radionuclide accumulation by a microbial sorbent].

Accumulation of a wide range of radionuclides by the microbial sorbent has been studied. The microbial sorbent represents granules stable in water solutions for a long period of time. The sorbent includes: concentrated biomass of metabolically active microorganisms, sources of carbon and energy, phosphorus, nitrogen, etc. Availability of nutrition sources in the sorbent provides for metabolic activity of microorganisms immobilized in granules. Metabolic activity of the sorbent was characterized. Physico-chemical sorption and metabolic activity of microorganisms lead to the extraction of a wide spectrum of radionuclides (51Cr, 54Mn, 60Co, 90Sr, 134Cs, 137Cs, 140La, 144Ce, 226Ra, 83Rb) from liquid radioactive waste. The extraction factor for some radionuclides was 10(5)-10(6). The waste sorbent may be utilized. Absence of water phase in the ash concentrate permits the radionuclides to be buried in borosilicate or volcanic glass (accepted time of existence 10(5)-10(7) years). The sorbent may be used to create new biotechnologies of radionuclide accumulation from water solutions.