A Study for Reductive Degradation and Surface Characteristics of Hexachloroethane by Iron Sulfide ($FeS,\;FeS_{2}$)

황화철($FeS,\;FeS_{2}$)을 이용한 헥사클로로에탄의 환원적 분해반응과 표면특성에 관한 연구

  • Park Sang-Won (Faculty of Environmental Science and Engineering, Keimyung University) ;
  • Kim Sung-Kuk (Faculty of Environmental Science and Engineering, Keimyung University) ;
  • Heo Jae-Eun (Faculty of Environmental Science and Engineering, Keimyung University)
  • Published : 2006.10.31

Abstract

The following results were obtained in the reductive degradation of hexachloroethane (HCA), and surface characteristics by using iron sulfide ($FeS,\;FeS_{2}$) mediators. HCA was degraded to pentachloroethane (PCA), tetrachloroethylene(PCE), trichloroethylene(TCE) and cis-l,2-dichloroethylene (cis-1,2-DCE) by complicated pathways such as hydrogenolysis, dehaloelimination and dehydrohalogenation. FeS had more rapid degradation rates of organic solvent than $FeS_{2}$. In liquidsolid reaction, the reaction rates of organic solvents were investigated to explain surface characteristics of FeS and $FeS_{2}$.. To determine surface characteristics of FeS and $FeS_{2}$, the specific surface area and surface potential of each mineral was determined and the hydrophilic site ($N_{s}$) was calculated. The specific surface area ($107.0470m^{2}/g\;and\;92.6374m^{2}/g$) and the $pH_{ZPC}$ of minerals ($FeS\;PH_{ZPC}=7.42,\;FeS_{2},\;PH_{ZPC}=7.80$) were measured. The results showed that the Ns of FeS and $FeS_{2}$ were $0.053\;site/mm^{2}\;and\;0.205\;site/mm^{2}$, respectively. $FeS_{2}$ had more hydrophilic surface than FeS. In other words, FeS have more hydrophobic surface site than $FeS_{2}$.

본 논문에서는 황화철($FeS,\;FeS_{2}$) 유기 용매의 환원적 분해 반응과의 표면특성의 관계에 대해서 다음과 같은 결과를 얻었다. hexachloroethane(HCA)은 수소첨가반응, 탈염소제거반응과 탈수소탈염소화반응으로 pentachloroethane(PCA), tetrachloroethylene(PCE), trichloroethylene(TCE)와 cis-1,2-dichloroethylene(cis-1,2-DCE)로 분해되었다. FeS와 $FeS_{2}$를 반응 매개물로 HCA에 대한 반응에서 FeS는 $FeS_{2}$보다 분해반응 속도가 빠르게 나타났다. FeS와 $FeS_{2}$의 표면 특성 연구에서 각 광물질에 대한 친수성 표면 자리(Ns)를 정량적으로 계산하기 위해서 비표면적 값($107.0470m^{2}/g$$92.6374m^{2}/g$)과 표면 전위를 측정에 측정된 $PH_{ZPC}(FeS,\;PH_{ZPC}=7.42,\;FeS_{2},\;PH_{ZPC}=7.80)$ 값을 이용해서 계산한 결과 FeS와 $FeS_{2}$$N_{s}$값은 각각 $0.053\;site/nm^{2},\;0.205\;site/nm^{2}$으로 나타났다. 그리고 0.2 g/L Fe광물질에 대한 실질적인 친수성 표면 농도는 각각 $3.303{\times}10^{-6}\;mol/L$$1.102{\times}10^{-5}\;mol/L$ 나타났다. $FeS_{2}$는 FeS에 비해 훨씬 친수성 표면임을 실험 결과 확인하였다. FeS와 $FeS_{2}$의 두 광물질 중에서 유기 용매의 환원 반응 속도는 FeS가 훨씬 빠르게 나타났다.

Keywords

References

  1. 김성국, 박상원, 2004, 철 광물에 의한 헥사클로에탄의 환원적 분해, 반응속도 연구, 한국지하수토양환경, 9(2), 20-27
  2. Barbash, J. and Roberts, P.V., 1986, Volatile organic chemical contamination of ground water resources in the U. S., J. Water Poll. Control Feder., 58, 343-348
  3. Benjamin, M.M. and Leckie, J.O., 1989, Multiple-site adsorption of Cd, Cu, Zn, and Pb on amophous iron oxyhydroxide. J. Colloid lntf. Sci., 79, 209
  4. Butler, E.C. and Kim, F.H., 1999, Kinetics of the transformation of trichloroethene and tetrachloroethylene by iron sulfide, Environ. Sci. Technol., 33, 2021-2027 https://doi.org/10.1021/es9809455
  5. Chern, J.M., 1987, Simulation of colloidal destabilization with metal coagulants, Ph. D Thesis, University of Delaware
  6. Davis, J.A.R., James, O., and Leckie, J.O., 1978, Surface ionization and complexation at the oxide/water interface, J. Colloid Intf Sci., 63, 480 https://doi.org/10.1016/S0021-9797(78)80009-5
  7. Day, R.E. and Parfitt, G.D., 1967, Adsorption at the solid-liquid interface. J. Phys. Chem., 71, 3073 https://doi.org/10.1021/j100868a057
  8. Fan, A.M., 1988, Trichloroethylene: water contamination and health risk assessment, In: G. W. Ware, Reviews of Environmental Contamination and Toxicology, Spronger-Verlag, New York, NY., p. 55-92
  9. Haim A., 1983, Mechanisms of electron transfer reaction, The bridged activated complex, Progr. Inorg. Chem., 30, 273-357 https://doi.org/10.1002/9780470166314.ch6
  10. Huang, C.P., 1981, The surface acidity of hydrous solide, adsorption of inorganics at solid-liquid interface, Ed., Anderson, M. A. and Rubin, A. J., Ann Arbor Science, Ann Arbor, Mich
  11. Matheson, L.J. and Trathnyek, G., 1994, Reductive dehalogenation of chlorinated methanes by iran metal. Environ. Sci. Technol., 28(12), 2045-2053 https://doi.org/10.1021/es00061a012
  12. Park, S.W. and Huang, C.P., 1989, Chemical substitution reaction between Cu(II) and Hg(II) and Hydrous CdS(s)., Water Research, 23, 1527 https://doi.org/10.1016/0043-1354(89)90118-8
  13. Park, S.W., 1987, Specific chemical reaction at the cadmimum sulfide-water interface. Ph. D. Thesis, University of Delaware
  14. Silverman J. and Dodson, R.W., 1952, The exchange reaction between the two oxidation states of iron in acid solution, J. Phys. Chem., 56, 846-852 https://doi.org/10.1021/j150499a007
  15. Sivavec, T.M., Homey, D.P., Baghel, S.S., 1995, Emerging technologies in hazardous waste management VII, ACS Special Symposium, September, 17-20
  16. Stumm, W., Kummert, R., and Sigg, L., 1980, A liquid exchange model for the adsorption of inorganic and organic ligands at hydrous oxide interference, Croat. Chim. Acta., 52, 291-302
  17. Sun, Z., Forsling, W., Ronngren, L., and Sjoberg, S., 1991, J. miner. Process, 33, 83-93 https://doi.org/10.1016/0301-7516(91)90044-J
  18. Vogel, T.M., Criddle, C.S., and McCarty, P.L., 1987, Transformations of halogenated aliphatic compounds. Environ. Sci. Technol., 21(8), 1023-1030
  19. Wehrli, B., 1990, Redox reactions of metal ions at mineral surfaces, Aquatic chemical kinetics: Reaction rates of processes in natural waters, Ed., Stumn, M., John Wiley & Sons, Inc., p. 311-336
  20. William, A.A., William, P.B., and Roberts, L., 1999, Polychlorinated ethane reaction with zero-valent zinc, pathways and rate control, J. Contaminant Hydrology, 40, 183-200 https://doi.org/10.1016/S0169-7722(99)00045-5