양이온-비이온 혼합계면활성제의 첨가가 영가철을 이용한 TCE환원에 미치는 영향

Effect of Surfactant on Reductive Dechlorination of Trichloroethylene by Zero-Valent Iron

  • 신민철 (금오공과대학교 환경공학과) ;
  • 최현덕 (금오공과대학교 환경공학과) ;
  • 양중석 (한국과학기술연구원 강릉분원) ;
  • 백기태 (금오공과대학교 환경공학과)
  • Shin, Min-Chul (Department of Environment Engineering, Kumoh National Institute of Technology) ;
  • Choi, Hyun-Dock (Department of Environment Engineering, Kumoh National Institute of Technology) ;
  • Yang, Jung-Seok (KIST Gangneung Institute) ;
  • Baek, Ki-Tae (Department of Environment Engineering, Kumoh National Institute of Technology)
  • 발행 : 2007.12.31

초록

트리클로로에틸렌(trichloroethyele, TCE)는 지하 환경으로 누출되었을 경우 대표적인 고밀도 불용성 유체(dense non aqueous phase liquids, DNAPLs)를 형성하여 토양과 지하수를 오염시키며, 계면활성제를 이용한 SEAR(Surfactant-enhanced aquifer remediation) 공법으로 처리를 하여도 소량이 계면활성제와 함께 지하수에 존재한다. 본 연구에서는 SEAR공법으로 처리 후 잔존하는 TCE가 계면활성제와 함께 존재할 때, 영가철(zero valent iron, ZVI)로 이루어진 투수성 반응벽체(PRB)에서의 TCE 거동을 조사하였다. 특히 계면활성제의 독성과 반응속도의 영향을 고려하여 양이온과 비이온 혼합 계면활성제의 영향을 중점적으로 다루었다. 혼합 계면활성제를 사용할 경우 ZVI를 이용한 TCE의 분해는 계면활성제의 구조에 따라 상당히 다른 경향을 보였다. TCE의 제거율을 살펴보면 비이온 계면활성제의 친수성기인 polyoxyethylene(POE) 사슬이 짧을 경우 양이온 계면활성제와 상관없이 거의 일정하였고, 상대적으로 긴 POE사슬일 경우 양이온 계면활성제의 종류와 첨가량에 따라 차이가 발생하였다. 친수성기가 트리메틸암모늄 (trimethylammonium)인 양이온 계면활성제가 피리디늄(pyridinium)를 가지는 양이온 계면활성제보다 더 높은 TCE 제거율을 보였다. 이러한 연구결과는 SEAR 후처리를 위해 PRB 적용시 잔존하는 계면활성제의 영향을 살펴보았으며 실제 현장적용의 중요한 자료로 이용될 수 있을 것으로 사료된다.

Trichloroethylene (TCE) is a representative dense non-aqueous phase liquid (DNAPL) and has contaminated substance environments including soil and groundwater due to leakage and careless. DNPAL, has been treated by surfactant-enhanced aquifer remediation (SEAR). After application of SEAR, groundwater contains still surfactant as well as little amount of residual TCE. Permeable reactive barrier using zero-valent iron (ZW) is a very effective technology to treat the residual TCE in groundwater. In this study, the effect of the residual surfactant on the reductive dechlorination of residual TCE was investigated using ZVI. Mixed surfactant composed of nonioinic surfactant and cationic surfactant was used as a residual surfactant because of toxicity and enhancement of dechlorination rate. Structure of surfactant affected significantly the decrhlorination rate of TCE. Mixed surfactant system with relatively short polyethylene oxide (PEO) chain in nonionic surfactant, cationic surfactant did not affect TCE dechlorination rate. However, mixed surfactant system with relatively long PEO chain in nonionic surfactant shows that TCE dechlorination rate was significantly dependent on fraction of cationic surfactant and HLB of nonionic surfactant. Cationic surfactant with trimethyl ammonium group enhanced reductive dechlorination rate compared to that surfactant with pyridinium group.

키워드

참고문헌

  1. 신승철,김영훈,고석오,2006,니켈로 코팅된 영가금속을 이용한 4-염화페놀의 환원제거율 평가,한국지하수토양환경학회지,11(3), 59-65
  2. Arnold, W.A. and Roberts, A.L., 2000, Pathways and Kinetics of Chlorinated Ethylene and Chlorinated Acetylene Reaction with Fe(O) Particles, Environ. Sci. Technol., 34, 1794-1805 https://doi.org/10.1021/es990884q
  3. Burris, D.R. and Campbell, T.J., 1995, Sorption of Trichloroethylene and Tetrachloroethylene in a Batch Reactive Metallic Iron-Water System, Environ. Sci. Technol., 29, 2850-2855 https://doi.org/10.1021/es00011a022
  4. Alessi, D.S. and Li, Z., 2001, Synergistic effect of cationic surfactants on perchloroethylene degradation by zero-valent iron, Environ. Sci Technol., 35, 3713-3717 https://doi.org/10.1021/es010564i
  5. Cho, H.-H. and Park, J.-W., 2006, Sorption and reduction of tetrachloroethylene with zero valent iron and amphiphilic moleewes, Chemosphere, 64, 1047-1052 https://doi.org/10.1016/j.chemosphere.2005.12.062
  6. Gillham, R.W. and O'Hannesin, S.F., 1994, Enhanced degradation of halogenated aliphatics by zero-valent iron, Ground Water, 32, 958-967 https://doi.org/10.1111/j.1745-6584.1994.tb00935.x
  7. Hooker, P.D. and Klabunde, K.J., 1994, Destructive Adsorption of Carbon Tetrachloride on Iron (III) Oxide, Environ. Sci. Technol., 28, 1243-1247 https://doi.org/10.1021/es00056a010
  8. Hua, J. and Hoffmann, M.R., 1996, Kinetics and Mechanism of the Sonolytic Degradation of $CCI_4$: Intermediates and Byproducts, Environ. Sci. Technol., 30, 864-871 https://doi.org/10.1021/es9502942
  9. Johnson, T.L. and Scherer, M.M., 1996, Kinetics of Halogenated Organic Compound Degradation by Iron Metal, Environ. Sci. Technol., 30, 2634-2640 https://doi.org/10.1021/es9600901
  10. Lee, J., Yang, J.-S., Kim, H.-J., Baek, K., and Yang, J.- W., 2005, Simultaneous removal of organic and inorganic contaminants by micellar enhanced ultrafiltration with mixed surfactant, Desalination, 184, 395-407 https://doi.org/10.1016/j.desal.2005.03.050
  11. Matheson, L.J. and Tratnyek, P.G, 1994, Reductive Dehalogenation of Chlorinated Methanes by Iron Metal, Environ. Sci. Technol, 28, 2045-2053 https://doi.org/10.1021/es00061a012
  12. Rao, P. and He, M., 2005, Adsorption of anionic and nonionic surfactant mixtures from synthetic detergents on soils, Chemosphere, 63, 1214-1221
  13. Schreier, C.G and Reinhard, M., 1994, Transformation of chlorinated organic compounds by iron and manganese powders in buffered water and in landfill leachate, Chemosphere, 29, 174-31753
  14. Pennel, K.D., Jin, M., Abriola, L.M., and Pope, G.A., 1994, Surfactant enhanced remediation of soil columns contaminated by residual tetrachloroethylene, J. Contam. Hydrol., 16(1),35-53 https://doi.org/10.1016/0169-7722(94)90071-X
  15. USEPA, 1998, Permeable Reactive Barrier Technologies For Contaminant Remediation. EPA 600-R-98-l25
  16. Zhao, B., Zhu, L., and Yang, K., 2006, Solubilization of DNAPLs by mixed surfactant: Reduction in partitioning losses of nonionic surfactant, Chemosphere, 62, 772-779 https://doi.org/10.1016/j.chemosphere.2005.04.080