本研究選用水溶解度相近但結構不同之PAHs與直鏈型烷類作為有機污染物標的物，以結構不同但容易掌握物化特性的染料（dye）作為土壤有機質的唯一來源，藉以單純化土壤有機質的結構與含量，進一步減少土壤有機質之變異性，以探討苯環結構間所產生之分子作用力對土壤-水系統中非離子有機化合物傳輸行為之影響。 實驗結果顯示：（1）高嶺土對兩種陽離子性染料-三苯環Basic Fuchsin與五苯環Victoria Blue B的吸附為單層L型吸附模式，鈣-蒙特石對非離子性染料Rosolic Acid的吸附等溫模式為S型。（2）對於相同NOC而言，分佈於組成相同但含量不同的土壤有機質之有機碳分佈係數為一常數，並且可維持至相當低的有機碳含量。（3）土壤有機碳含量極低時，非離子有機化合物的有機碳分佈係數會明顯的偏高，分佈作用不再是其主要吸持機制。（4）當土壤有機質含量不至於太低時，PAHs有機碳分佈係數明顯大於水溶解度相近的直鏈型非離子有機化合物，推測PAHs特殊的分佈行為與土壤中有機質芳香性有關。（5）PAHs的分佈與土壤有機質芳香族化合物成一定的正相關性。 This study is to investigate the effects of benzene rings interaction on the transport of nonionic organic contaminants (NOCs) in the soil/water system. The NOCs used in this study were polycyclic aromatic hydrocarbons (PAHs) and straight chain NOCs that have similar water solubilities. Dyes with varied structures were used to consist of soil organic matter (SOM) that is regarded as the partition medium in order to purify the complicated soil organic phase and control the content of organic carbon within. The sorption isotherms of Basic Fuchsin as well as Victoria Blue B are classified as L-type. The sorption isotherm of nonionic Rosolic Acid, which shows S-type, depicts a two steps sorption mechanism. The measured partition coefficients of an individual NOC between SOM and water (i.e., Koc value) remain a constant to a certain extent of organic carbon content for the clays with same organic component. At a very low dye loading, the resulting mineral-sorbed dyes appear to form a thin organic film, which effectively “adsorbs” the NOCs, resulting in very high Koc values. At similar water solubilities, the Koc values for PAHs were always higher than that of straight chain NOCs. The enhanced partition of PAHs over other nonpolar straight chain NOCs with similar water solubility provides an account of the distinctive partition behavior in improved aromatic SOM. To further elucidate this trend, higher Koc values of the used PAHs partitioning in the greater aromatic SOM were found.
