화학공학소재연구정보센터
HWAHAK KONGHAK, Vol.36, No.4, 554-561, August, 1998
수정된 EPICS법에 의한 환경오염물질의 Air/Water 분배계수 측정과 분배계수와 물성과의 상관관계
Determination of Air/Water Partition Coefficient for Environmental Pollutant by Using Modified EPICS Method and the Relationship between Partition Coefficient and Physical Properties
초록
환경에 노출된 유해물질이 소멸되기까지는 이동현상과 혼합현상 그리고 화합물의 구조적 교체과정이 진행되며, 이중에 이동현상은 분배계수로 나타내어진다. 여러 분배계수 중 air/water분배계수(Kaw)를 bubble 칼럼을 이용하여 수정된 EPICS(equilibrium partitioning in closed system)법으로 측정하였다. 실험방법의 정확성과 재현성을 위해 n-alkane계의 Kaw를 측정하고 문헌치와 비교한 결과 1%내의 작은 편차로 잘 일치함을 확인하였으므로 n-alkene, 방향족과 염소화합물의 Kaw를 측정하고, 포화증기압과 물에 대한 포화용해도로부터 Henry 상수를 계산하였다. Henry 상수와 몰부피, 용해도, 포화증기압과의 상관관계에서는, 염소로 치환된 벤젠화합물을 제외하고는, 모든 화합물에서 몰부피에 따라서 증가하고 용해도와 포화증기압에 대해서는 감소하는 경향을 보였다. 또한 단일결합과 같이 결합력이 약한 화학물질일수록 Kaw는 증가하는 경향을 보였다.
Environmental organic chemicals disappear by means of transport and mixing phenomena and alterations of the structure of a compound. The transport phenomena can be represented by partition coefficient. In this work, the air/water partition coefficient(Kaw) was measured by using our own modified EPICS(equilibrium partitioning in closed system) method. The accuracy and reproducibility of this method were reliable since measured data were agreed well with the literature values within 1% average deviation for n-alkanes. The Kaw and Henry's law constants for n-alkenes, aromatic and chlorinated compounds were measured. The relationships between Kaw and molar volume, vapor pressure and water solubility were also analysed. The Kaw was linearly proportional to molar volume and inversely proportional to vapor pressure and water solubility except chlorinated benzene compounds. The chlorinated benzene compounds didn't show the consistent tendency for molar volume, vapor pressure and water solubility. It may be caused from the difference of intermolecular force. The Kaw was changed by difference of molecular structure. The weaker the bond energy of chemicals, the larger the Kaw of chemicals.
  1. Mackay D, "Multimedia Environmental Model; The Fugacity Approach," Lewise Pub. Inc. (1991)
  2. Fujita T, Iwasa J, Hansch C, J. Am. Chem. Soc., 86, 5175 (1964) 
  3. Woodburn KB, Doucette WJ, Andren AW, Environ. Sci. Technol., 18, 16 (1984)
  4. Bidleman TF, Anal. Chem., 56, 3 (1984)
  5. Fendinger NJ, Glotfelty DE, Environ. Sci. Technol., 22, 1289 (1988) 
  6. McAuliffe CD, Chem. Tech., 1, 46 (1971)
  7. Lincoff AH, Gossett JM, "Gas Transfer at Water Surface," Brutsaert, W., Jirka, G.H. ed., Reidel, Dordrecht, Holland (1984)
  8. Park SJ, Ryu SA, Han SD, HWAHAK KONGHAK, 35(3), 401 (1997)
  9. Park SJ, Han SD, Ryu SA, HWAHAK KONGHAK, 35(6), 915 (1997)
  10. Gossett JM, Environ. Sci. Technol., 21, 202 (1987) 
  11. Leo A, Hansch C, Elkins D, Chem. Rev., 71, 525 (1971) 
  12. Mackay D, Shiu WY, J. Phys. Chem. Ref. Data, 10, 4 (1981)
  13. Schwarzenbach RP, Gschwend PM, Imboden DM, "Environmental Organic Chemistry," John Wiley & Sons, Inc. (1993)
  14. Gmehling J, Onken U, Arlt W, "Vapor-Liquid Equilibrium Data Collection," DECHEMA (1981)
  15. Stephenson RM, Malanowski S, "Handbook of the Thermodynamics of Organic Compounds," Elsevier (1987)