| Loess soils topographically cover the vast land in northwest China where oil fields are widely exploited in the recent four decades, and resulted in the severe petroleum contamination of soils and water resources through various ways including spillage of crude oil nearby the drilling wells, leakage from storage tanks and pipelines. As a class of petroleum compounds, polycyclic aromatic hydrocarbons (PAHs) present a group of compounds with two or more fused aromatic rings that are mutagenic, carcinogenic and teratogenic, and PAHs are included in the CERLA Priority List of Hazardous Substances. At present it was specially regarded to study the transfer and transform of PAHs in domestic and international, and was expected to forecast contamination rule of PAHs in soil and grouderwater and to provide a theoretical basis of studying contamination control and remediation. At studying the rule of transfer and transform, soil sorption to the compound of PAHs have a very important function. The sorption process was influenced with many factors. If these factors can be predominated, we can avoid or lessen contamination of PAHs to soil and groundwater through intensifying or controlling some factors of sorption process. The natural environment of western region was contaminated with PAHs, and it was potential to be contaminated seriously in a very long period. Studying the transfer and transform of PAHs in the soils, it can help to provided a scientific basis to protect environment and manage contamination without reference to manage the soils and water resources contaminated with PAHs or to protect the soils and water resources uncontaminated with PAHs.Chapter 1.Advances in the Research on the Transfer and Transform of PolycyclicAromatic Hydrocarbons in Loess SoilsA review is reported with 68 references about the formation mechanism and distribution of polycyclic aromatic hydrocarbons, the transfer and transform study and sorption and desorption, meantime reviewing the research significance on the transfer and transform of polycyclic aromatic hydrocarbons in soils.Chapter 2.Analysis of Petroleum Pollutants in Yumen's Mining Areas by Gas Chromatography and Mass ChromatographyThe oil-field of Yumen is the one of the large oil-fields exploited more early in our country. Through exploiting and using in the recent four decades, it resulted in the severe petroleum contamination of soils and water resources including spillage of crude oil nearby the drilling wells, leakage from storage tanks and pipelines. Petroleum is a kind of complex mixture containing hydrocarbon and non-hydrocarbon compounds with various physical and chemical properties. Gas chromatography and mass spectrometry were used to analysis crude oil in pipline and bulk, and water samples comprising petroleum contaminants at separate sites in Yumen's mining areas. The results show that there were priority pollutants that were published by Environmental Protection Agency in the United States. More information of petroleum compounds were obtained by using gas chromatography and mass spectrometry than by traditional methods.Chapter 3.Sorption Kinetics of Naphthalene and Phenanthrene in Loess SoilsNaphthalene and phenanthrene were chosen as organic contaminant indicators in loess soil modified by the cation surfactant hexadecyltrimethylammonium (HDTMA) bromide. The kinetic behavior of sorption during transport in both natural and modified loess soil was studied. The results indicated that sorption rate in the cation surfactant modified loess soils was at least 3 times faster than that of the natural soil. A first-order kinetics model fitted the sorption data well for both soils. The sorption rates of the two organic compounds were related to their primary residuai quantity on the soils. The rate constants, however, displayed negative correlation with increasing temperature. Sorption rates of naphthalene and phenanthrene on loess soils and and the modified loess soils with a cation surfactant hexadecyltrimethylammonium (HDTMA) bromid...
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