土壤中污染物的整治,易受到土壤有機碳所影響,農作廢棄物就地未完全燃燒所產生之黑碳,對於疏水性有機污染物傳輸的影響尚未被探討。本研究將稻桿不完全燃燒後之黑碳作為吸持劑,探討兩種PAHs(naphthalene、anthracene)在含吸持劑及不含吸持劑之土壤中的傳輸及整治。 實驗結果顯示,存在於環境中的黑碳對高疏水性多環芳香烴- anthracene確實有明顯的增強吸附現象,但土壤本身的特性仍不可忽視;低疏水性多環芳香烴- naphthalene的吸附較不受到土壤性質影響,且所含黑碳比例不同造成的影響也較輕微。就單位重量所吸附之濃度而言,土壤中的有機碳所吸附之濃度,遠不及所添加之吸持劑中有機碳所吸附之濃度,故農作廢棄物不完全燃燒所產生的黑碳,以單位重量有機碳而言,其對於疏水性之有機污染的吸附明顯高於土壤有機碳之吸附。 在模擬污染物在地下水的傳輸之管柱實驗中,以界面活性劑Tween 80與Triton X-100對已吸附PAHs之土壤進行脫附,界面活性劑對於低疏水性naphthalene污染之實驗土確有增溶作用,且脫附效果受界面活性劑之分子結構的影響較大,Triton X-100的疏水性高(HLB值較高)於Tween 80,使得Triton X-100脫附效果大於Tween 80;對於較高疏水性anthracene污染之實驗土進行脫附時,界面活性劑的濃度成為主要影響因子,而非分子結構,因所使用之Tween 80濃度為臨界微胞濃度(CMC)之68倍,而Triton X-100僅為10 CMC,所以Tween 80脫附效果大於Triton X-100。
The remediation of contaminated soil is influenced by soil organic carbon. The black carbons resulted from the uncompleted combustion did not be discussed thoroughly for their effect on the transport of hydrophobic organic contaminant (HOC). This research focused on the sorption of two PAHs (naphthalene, anthracene) influenced by the black carbon. The result shows that there is an increased sorption existed between black carbon and high hydrophobic polyoyclic aromatic hydrocarbons (PAHs) such as antharcene, and the characteristics of soil could not be ignored either. The sorption of less hydrophobic compounds such as naphthalene was influenced slightly by soil characteristics and the black carbon. Comparing on the base of unit weight, the sorption of PAHs on soil organic carbon is far less than that by the black carbon. The column experiments were used to imitate the contaminate transportation in groundwater. Tween 80 and Triton X-100 were used as desorbing surfactants. The desorption of less hydrophobic PAH (naphthalene) affected greatly by the molecule structure of surfactant. The Hydrophile-Lipophile Balance of Triton X-100 are higher than that of Tween 80, so Triton X-100 has higher desorption effect. For the desorption of high hydrophobic contaminant (anthracene), the concentration of surfactants becomes the dominant factor. The concentration of surfactant Tween 80 concentration is 68 critical micelle concentration (CMC), and Triton X-100 is only 10 CMC, so the desorption effect of Tween 80 is better than that by Triton X-100.