The environmental behaviors of polycyclic aromatic hydrocarbons (PAHs) are mainly governed by their solubility and partitioning properties on soil media in a subsurface system. In surfactant-enhanced remediation (SER) systems, surfactant plays a critical role in remediation. In this study, sorptive behaviors and partitioning of naphthalene in soils in the presence of surfactants were investigated. Silica and kaolin with low organic carbon contents and a natural soil with relatively higher organic carbon content were used as model sorbents. A nonionic surfactant, Triton X-100, was used to enhance dissolution of naphthalene. Sorption kinetics of naphthalene onto silica, kaolin and natural soil were investigated and analyzed using several kinetic models. The two compartment first-order kinetic model (TCFOKM) was fitted better than the other models. From the results of TCFOKM, the fast sorption coefficient of naphthalene (k1) was in the order of silica > kaolin > natural soil, whereas the slow sorbing fraction (k2) was in the reverse order. Sorption isotherms of naphthalene were linear with organic carbon content (foc) in soils, while those of Triton X-100 were nonlinear and correlated with CEC and BET surface area. Sorption of Triton X-100 was higher than that of naphthalene in all soils. The effectiveness of a SER system depends on the distribution coefficient (KD) of naphthalene between mobile and immobile phases. In surfactant-sorbed soils, naphthalene was adsorbed onto the soil surface and also partitioned onto the sorbed surfactant. The partition coefficient (KD) of naphthalene increased with surfactant concentration. However, the KD decreased as the surfactant concentration increased above CMC in all soils. This indicates that naphthalene was partitioned competitively onto both sorbed surfactants (immobile phase) and micelles (mobile phase). For the mineral soils such as silica and kaolin, naphthalene removal by mobile phase would be better than that by immobile phase because the distribution of naphthalene onto the micelles (Kmic) increased with the nonionic surfactant concentration (Triton X-100). For the natural soil with relatively higher organic carbon content, however, the naphthalene removal by immobile phase would be better than that by mobile phase, because a high amount of Triton X-100 could be sorbed onto the natural soil and the sorbed surfactant also could sorb the relatively higher amount of naphthalene.

Abstract
 1. 서 론
 2. 수착 모델
  2.1. 수착 동력학 모델
  2.2. 수착 모델
  2.3. 마이셀에 의한 나프탈렌의 용해도 증가
  2.4. 수착된 계면활성제에 나프탈렌의 분배
 3. 재료 및 방법
  3.1. 실험 재료
  3.2. 나프탈렌의 수착 동력학 실험
  3.3. 나프탈렌의 수착 실험
  3.4. 계면활성제의 임계 마이셀 농도 (CMC) 측정
  3.5. 계면활성제의 수착 실험
  3.6. 계면활성제에 의한 나프탈렌의 용해도 증가
  3.7. 수착된 계면활성제에 대한 나프탈렌의 분배
 4. 결과 및 고찰
  4.1. 나프탈렌의 수착 속도
  4.2. 나프탈렌의 수착
  4.3. Triton X-100의 수착
  4.4. Triton X-100에 의한 나프탈렌의 용해도 증가
  4.5. 토양에 수착된 계면활성제에 대한 나프탈렌의 분배
 5. 결 론
 참 고 문 헌

• 하동현(경북대학교 환경공학과) | Dong-Hyun Ha (Department of Environmental Engineering, Kyungpook National University)
• 신원식(경북대학교 환경공학과) | Won Sik Shin (Department of Environmental Engineering, Kyungpook National University) Corresponding Author
• 오상화(경북대학교 환경공학과) | Sanghwa Oh (Department of Environmental Engineering, Kyungpook National University)
• 송동익(경북대학교 화학공학과) | Dong-Ik Song (Department of Chemical Engineering, Kyungpook National University)
• 고석오(경희대학교 토목공학과) | Seok-Oh Ko (Department of Civil Engineering, Kyunghee University)