Importance of Sorption of Organic Pollutants, and Especially PAHs, to Soot in the Environment

9800485 Gschwend本项目的目的是确定烟尘的重要性，其中大部分是在燃烧过程中产生的，在吸附沉积物和土壤中的有机污染物。 煤烟对污染物的吸附作用限制了污染物在土壤和沉积物中的流动性，并控制了它们被生物降解的有效性。 在这个项目中，煤烟碳将被隔离从污染沉积物在两个地点与对比历史的污染物输入。 一个国家通过直接的大气沉降物、风暴期间的地表径流和渗漏释放到地下水中，从邻近的土地上接受污染物。 另一个地点是沿海港口，沉积物受到多环芳烃和多氯联苯的严重污染。 这些来源的碳烟将表征其物理性质，去除其吸附的污染物，然后用于实验测定其吸附性能。 计划使用的多环芳烃山梨酸酯包括萘、菲和芘，表现出一定范围的疏水性。 平面和非平面多氯联苯的混合物也将进行评估，以确定只有在两者分别引入环境后才与烟灰碳接触的化合物的行为。预计该项目的结果将有助于评估烟灰碳在影响净化被多环芳烃和其他污染物吸附到这类碳上的沉积物和土壤的工艺和系统的工程设计方面所发挥的作用。 了解碳烟抑制这些污染物释放和迁移的能力，可能在确定是否需要进行去污程序方面发挥重要作用，并且当发现需要时，必须在多大程度上进行去污，以达到污染物与碳烟结合并不再构成环境威胁的水平。

9800485 Gschwend The objective of this project is to determine the significance of soot, much of which is produced during combustion processes, in sorption of organic contaminants from sediments and soil. Sorption of contaminants by soot limits the mobility of contaminants in soil and sediments and controls their availability for being degraded biologically. In this project, soot carbon will be isolated from contaminated sediments at two sites with contrasting histories of pollutant inputs. One has received contaminants from adjacent land by direct atmospheric fallout, overland flow during storms and release to groundwater from exfiltration. The other site is a coastal harbor location, sediments at which have been heavily contaminated by polycyclic aromatic hydrocarbons and polychlorinated biphenyls. The soot carbons from these sources will be characterized for their physical properties, their adsorbed pollutants removed and then used for experimental determination of their sorption properties. The polycyclic aromatic hydrocarbon sorbates planned for use include naphthalene, phenanthrene and pyrene, exhibiting a range of hydrophobicities. A mix of planar and nonplanar polychlorinated biphenyls will also be evaluated to determine the behavior of compounds that come in contact with the soot carbon only after both have been separately introduced into the environment. Results of this project are expected to enable assessment of the role that soot carbons play in influencing the engineering design of processes and systems for decontamination of sediments and soils contaminated by polycyclic aromatic hydrocarbons and other contaminants that are sorbed to this type of carbon. Knowledge of the capacity that soot carbon has for restraining release and migration of those contaminants is likely to play an important role in determining the need for engaging in decontamination procedures, and when found to be needed, the extent to which decontamination must be practiced to reach the level at which contaminants are bound to soot carbon and no longer pose an environmental threat.