Economic and Environmental Geology (자원환경지질)

The Korean Society of Economic and Environmental Geology (대한자원환경지질학회)
권호 표지

Removal Characteristics of Dissolved Uranium by Shewanella p. and Application to Radioactive Waste Disposal

스와넬라균(Shewanella p.)에 의한 용존우라늄 제거 특성 및 방사성폐기물 처분에의 응용

  • Lee, Seung-Yeop (Division of Radwaste Technology Development, Korea Atomic Energy Research Institute) ;
  • Baik, Min-Hoon (Division of Radwaste Technology Development, Korea Atomic Energy Research Institute) ;
  • Song, Jun-Kyu (Young Sciences Inc.)
  • 이승엽 (한국원자력연구원 방사성폐기물기술개발부) ;
  • 백민훈 (한국원자력연구원 방사성폐기물기술개발부) ;
  • 송준규 ((주)영사이언스)
  • Published : 2009.10.28
Download PDF
⟨ Previous Next ⟩

Abstract

An experimental removal of dissolved uranium (U) exsiting as uranyl ion (${UO_2}^{2+}$) was carried out using Shewanella p., iron-reducing bacterium. By the microbial reductive reaction, initial U concentration ($50{\mu}M$) was constantly decreased, and most U were removed from solution after 2 weeks. Major mechanism that U was removed from the solution was adsorption, precipitation and mineralization on the microbe surface. Under the transmission electron microscopy, the U adsorbed on the microbe was observed as being crystallized and eventually enlarged to several ${\mu}m$ sizes of minerals by combining with individual microbes and organic exudates. It seems that such U growth and mineralization on the microbial surface could affect the U behavior in a radioactive waste disposal site. Thus, the biogechemical reaction of metal-reducing bacteria observed in this experiment could give an affirmative measure that the microbial activity may retard U movement in subsurface environment.

물속에 우라닐이온(${UO_2}^{2+}$) 형태로 존재하는 산화우라늄을 철환원세균인 스와넬라균(Shewanella p.)을 이용하여 제거하는 실험을 수행하였다. 용액상의 우라늄 초기농도는 $50{\mu}M$ 이었으며 미생물과의 반응에 의해 점차 그 농도가 감소하였고, 약 2주 후에 거의 대부분의 우라늄이 제거되었다. 우라늄이 제거된 기작은 대부분 미생물 표면에 대한 흡착, 침전 및 광물화에 의한 것이었다. 투과전자현미경으로 관찰한 결과로는 미생물 표면에 흡착되어 점차 결정화되어가는 우라늄이 큰 광물로 성장하고 여러 미생물개체 및 유기분비물과의 결합을 통해 그 크기가 수 ${\mu}m$ 이상으로 커져가는 것을 확인하였다. 이러한 미생물에 의한 우라늄 광물의 성장 및 결합은 방사성폐기물처분장의 우라늄 거동에 큰 영향을 끼칠 수 있으며, 특별히 본 실험에서 관찰한 생지화학적인 금속환원미생물의 역할에 의해 지하 우라늄의 이동이 상당히 지연되는 효과를 거둘 수 있을 것으로 사료된다.

Keywords

References

  1. Baik, M.H., Lee, S.Y., Lee, J.K., Kim, S.S., Park, C.K. and Choi, J.W. (2008) Review and complication of data on radionuclide migration and retardation for the performance assessment of HLW repository in Korea. Nucl. Eng. Technol., v.40, p.593-606 https://doi.org/10.5516/NET.2008.40.7.593
  2. Bargar, J.R., Bernier-Latmani, R., Giammar, D.E. and Tebo, B.M. (2008) Biogenic uraninite nanoparticles and their importance for uranium remediation. Elements, v.4, p.407-412 https://doi.org/10.2113/gselements.4.6.407
  3. Ehrlich, H.L. (1990) Geomicrobiology. 2nd(ed.), Marcel Dekker, New York, 646p
  4. Fredrickson, J.K., Zachara, J.M., Kennedy, D.W., Duff, M.C., Gorby, Y.A., Li, S.M.W. and Krupka, K.M. (2000) Reduction of U(VI) in goethite (alpha-FeOOH) suspensions by a dissimilatory metal-reducing bacterium. Geochim. Cosmochim. Acta, v.64, p.3085-3098 https://doi.org/10.1016/S0016-7037(00)00397-5
  5. Haas, J.R., Dichristina, T.J. and Wade, R. (2001) Thermodynamics of U(VI) sorption onto Shewanella putrefaciens. Chem. Geol., v.180, p.33-54 https://doi.org/10.1016/S0009-2541(01)00304-7
  6. Istok, J.D., Senko, J.M., Krumholz, L.R., Watson, D., Bogle, M.A., Peacock, A., Chang, Y.J. and White, D.C. (2004) In situ bioreduction of technetium and uranium in a nitrate-contaminated aquifer. Environ. Sci. Technol., v.38, p.468-475 https://doi.org/10.1021/es034639p
  7. Koppi, A.J., Edis, R., Field, D.J., Geering, H.R., Klessa, D.A. and Cockayne, J.H. (1996) Rare earth element trends and cerium-uranium-manganese associations in weathered rock from Koongarra, Northern Territory, Australia. Geochim. Cosmochim. Acta, v.60, p.1695-1707 https://doi.org/10.1016/0016-7037(96)00047-6
  8. Lee, J.O., Lee, K.J. and Cho, W.J. (1997) Sorption and diffusion of I-125 and Sr-90 in a mixture of bentonite and crushed granite backfill of a radioactive waste repository. Radiochim. Acta, v.76, p.143-151
  9. Lee, S.Y., Baik, M.H. and Lee, Y.B. (2009) Adsorption of uranyl ions and microscale distribution on Fe-bearing mica. Appl. Clay Sci., v.44, p.259-264 https://doi.org/10.1016/j.clay.2009.03.002
  10. Lloyd, J.R., Renshaw, J.C., May, I., Livens, F.R., Burke, I.T., Mortimerc, R.J.G. and Morris, K. (2005) Biotransformation of radioactive waste: Microbial reduction of actinides and fission products. J. Nucl. Radiochem. Sci., v.6, p.17-20 https://doi.org/10.14494/jnrs2000.6.17
  11. Lovley, D.R., Phillips, E.J.P., Gorby, Y.A. and Landa, E.R. (1991) Microbial reduction of uranium. Nature, v.350, p.413-416 https://doi.org/10.1038/350413a0
  12. Murakami, T., Sato, T., Ohnuki, T. and Isobe, H. (2005) Field evidence for uranium nanocrystallization and its implications for uranium transport. Chem. Geol., v.221, p.117-126 https://doi.org/10.1016/j.chemgeo.2005.04.004
  13. Nealson, K.H. and Stahl, D.A. (1997) Microorganisms and biogeochemical cycles: what can we learn from layered microbial communities? In Banfield, J.F. and Nealson, K.H.(ed.) Geomicrobiology: Interactions between microbes and minerals. Reviews in Mineralogy, vol.35, Mineralogical Society of America
  14. Pusch, R. and Carlsson, T. (1985) The physical state of Na-smectite used as barrier component. Eng. Geol., v.21, p.257-265 https://doi.org/10.1016/0013-7952(85)90016-X
  15. Sato, T., Murakami, T., Yanase, N., Isobe, H., Payne, T.E. and Airey, P.L. (1997) Iron nodules scanvenging uranium from groundwater. Environ. Sci. Technol., v.31, p.2854-2858 https://doi.org/10.1021/es970058m
  16. Suzuki, Y., Kelly, S.D., Kemner, K.M. and Banfield, J.F. (2002) Nanometre-size products of uranium bioreduction. Nature, v.419, p.134 https://doi.org/10.1038/419134a
  17. Truex, M.J., Peyton, B.M., Valentine, N.B. and Gorby, Y.A. (1997) Kinetics of U(VI) reduction by a dissimilatory Fe(III)-reducing bacterium under nongrowth conditions. Biotechnol. Bioeng., v.555, p.490-496