Nonionic Organic Compounds uptake on the low organic matter soil
| Autor: | Tzu-Jung Hsu, 許慈容 |
|---|---|
| Rok vydání: | 2006 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 94 In the water-saturated soil system, the mineral phase of soil is occupied by the polar water molecules. The extent of soil uptake for contaminants is mainly controlled by partitioning to the soil organic matter and the sorption isotherms are all relatively linear. Normally, organic carbon normalized partition coefficient (Koc) is used to predict the distribution of NOCs (Nonionic Organic Compounds, NOCs) in the soil–water system. Our previous finding indicate that the quantity and the composition of soil organic matter would affect the organic carbon normalized partition coefficient (Koc). Therefore, the objective for our study is to elucidate the variation of Koc under the extremely low soil organic matter content. Na-montmorillonite was used as adsorbent. The cation dye and surfactant that adsorbed on the soil surface were the only source of the soil organic matter. Organochemical-clay complexes were prepared by reacting clay with organic cation. Adsorption isothems of NOCs (BTEX and organochlorine pesticides) were obtained by the batch experiment. The experimental results show that the Koc of the NOCs is significantly higher than natural soil about 4~10 times. When the soil was covered by only a few organic matter, the polar force of the soil mineral can penetrate organic matter film react on the NOCs. The predominant effect of SOM in this case is more like adsorption than partitioning. Moreover, all adsorption isotherms became a little crooked in this condition. Furthermore, BTEX which with higher polarity are profoundly affected by the polarity of soil mineral phase. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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