Behavior of plutonium interacting with bentonite and sulfate-reducing anaerobic bacteria
- National Research Council of Canada, Ottawa, Ontario (Canada)
- Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst.
- Ishikawajima-Harima Heavy Industries Co. Ltd., Isogo, Yokohama (Japan)
- Power Reactor and Nuclear Fuel Development Co., Tokai, Ibaraki (Japan)
The interactions between sulfate reducing anaerobic bacteria and plutonium, with or without bentonite present, were investigated using distribution coefficients [Kd (ml/g)] as an index of the radionuclide behavior. Plutonium Kds for living bacteria varied within a large range, from 1,804 to 112,952, depending on the pH, while the Kds ranged from 1,180 to 5,931 for dead bacteria. In general, living bacteria had higher plutonium Kds than dead bacteria. Furthermore, the higher Kd values of 39,677 to 106,915 for living bacteria were obtained for a pH range between 6.83 and 8.25, while no visible pH effect was observed for dead bacteria. These Kd values were obtained using tracers for both {sup 236}Pu and {sup 239}Pu, which can check the experimental procedures and mass balance. Another comparison was conducted for plutonium Kd values of mixtures of living bacteria with bentonite and sterilized bacteria with bentonite. The range of Kd values for the non-sterilized bacteria with bentonite were 1,194 to 83,648 while Kd values for the sterilized bacteria with bentonite were from 624 to 17,236. Again, the Kd values for the living bacteria with bentonite were higher than those of sterilized bacteria with bentonite. In other words, the presence of living anaerobic bacteria with bentonite increased, by roughly 50 times, the Kd values of {sup 239}Pu when compared to the mixture of dead bacteria with bentonite. The results indicate that the effects of anaerobic bacteria within the engineered barrier system (in this case bentonite) will play a significant role in the behavior of plutonium in geologic repositories.
- OSTI ID:
- 572199
- Report Number(s):
- CONF-961202-; TRN: 98:003766
- Resource Relation:
- Conference: 1996 Fall meeting of the Materials Research Society (MRS), Boston, MA (United States), 2-6 Dec 1996; Other Information: PBD: 1997; Related Information: Is Part Of Scientific basis for nuclear waste management XX; Gray, W.J. [ed.] [Pacific Northwest National Lab., Richland, WA (United States)]; Triay, I.R. [ed.] [Los Alamos National Lab., NM (United States)]; PB: 1389 p.; Materials Research Society symposium proceedings, Volume 465
- Country of Publication:
- United States
- Language:
- English
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