Soil, Water and Environmental Science Department, School of Earth and Environmental Sciences, University of Arizona, Tucson, AZ 85721, USA.
Chemosphere. 2013 Jan;90(2):459-63. doi: 10.1016/j.chemosphere.2012.07.061. Epub 2012 Aug 24.
The objective of this research was to examine the potential for intercalation of trichloroethene (TCE) by clay minerals associated with aquifer sediments. Sediment samples were collected from a field site in Tucson, AZ. Two widely used Montmorillonite specimen clays were employed as controls. X-ray diffraction, conducted with a controlled-environment chamber, was used to characterize smectite interlayer d-spacing for three treatments (bulk air-dry sample, sample mixed with synthetic groundwater, sample mixed with TCE-saturated synthetic groundwater). The results show that the d-spacing measured for the samples treated with TCE-saturated synthetic groundwater are larger (~26%) than those of the untreated samples for all field samples as well as the specimen clays. These results indicate that TCE was intercalated by the clay minerals, which may have contributed to the extensive elution tailing observed in prior miscible-displacement experiments conducted with this sediment.
本研究旨在探讨与含水层沉积物相关的粘土矿物对三氯乙烯（TCE）的插层潜力。从亚利桑那州图森市的一个野外地点采集了沉积物样本。两种广泛使用的蒙脱土标本粘土被用作对照。使用带有控温控湿腔的 X 射线衍射来对三种处理方式（原土样、与合成地下水混合的土样、与 TCE 饱和合成地下水混合的土样）的蒙脱石层间间距进行了特征描述。结果表明，与未处理的样本相比，用 TCE 饱和合成地下水处理的样本的层间距更大（~26%），这对所有野外样本和标本粘土都是如此。这些结果表明 TCE 被粘土矿物插层，这可能是先前在该沉积物上进行的可混相驱替实验中观察到的广泛洗脱拖尾的原因。
