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5441921 
Technical Report 
Sorption of selected volatile organic constituents of jet fuels and solvents on natural sorbents from gas and solution phases 
Rao, PSC; Rhue, RD; Johnston, CT; Oguda, RA 
1988 
University of Florida 
Gainesville, FL 
ESL-TR-88-02 
English 
Sorption of selected volatile organic constituents (VOC) of jet fuels and solvents on several natural sorbents from the gas and aqueous phases was investigated. The sorbates studied were trans-1,2-dichloroethylene; 1,2-dichloroethane; trichloroethylene; 1,1,2,2-tetrachloroethane; toluene; ethylbenzene; p-xylene; o-xylene; and cyclohexane. The sorbents used included clays (kaolin, montmorillonite, SAz-1), soils (Webster and Oldsmar), and aquifer materials (Borden and Lula). Sorption from the vapor phase was studied using three techniques: the headspace analysis method, dynamic flow method, and a gas chromatographic method. Sorption of VOC on anhydrous sorbents and sorbents in equilibrium with water at different relative humidities was examined. The energetics of sorption were characterized by measuring VOC sorption at several temperatures. Miscible displacement techniques were used to measure effluent breakthrough curves (BTC) for trichloroethylene (TCE) and p-xylene displacement in saturated columns of Lula and Borden aquifer materials. The BTC measured at two velocities were used to evaluate the utility of a bicontinuum model for predicting sorption nonequilibrium during transport. BTC measured for displacement of binary mixtures (TCE plus p-xylene) and single solute (TCE or p-xylene) were identical, suggesting no competitive sorption. Methods were developed for molecular-level investigations of sorption on clays using Fourier Transform Infrared (FT-IR) spectroscopic techniques. These methods were used to observe IR spectra of clay minerals as dry powders, thin self-supporting films, and aqueous slurries. IR spectra were obtained for kaolinite and montmorillonite clays as well as for p-xylene adsorbed on homoinic montmorillonite, both in the presence and absence of water. The application of FT-IR methods to study the p-xylene-clay complex provided a sensitive in-situ method to observe the surface-mediated transformation of the p-xylene on the montmorillonite sample as the clay was dehydrated. Such a transformation was not noted on Na-montmorillonite. (Author 's abstract) 
Water Resources Abstracts; Path of pollutants; Sorption; Volatile organic compounds; Solvents; Water pollution treatment; Organic compounds; Dichloroethylene; Dichloroethane; Trichloroethylene; Tetrachloroethane; Soil contamination; Chemical analysis; Gas chromatography