Nonaqueous phase liquids density

Sanchez, M. and Ely, R., 1998, Recovery of Trichloroethylene from a Bench-Scale Aquifer by Density Manipulations In Nonaqueous-Phase Liquids — Remediation of Chlorinated and Recalcitrant Compounds (edited by G. B. Wickramanayake and R. E. Hinchee), Battelle Press, Columbus, OH, pp. 181-185. 

In Situ Density Modification of Entrapped Dense Nonaqueous-Phase Liquids (DNAPLs) using Surfactant/Alcohol Solutions... 

Dense nonaqueous-phase liquids (DNAPLs) are widespread at contaminated sites, where they are often distributed deep in aquifers due to their high densities [US EPA, 1993], Surfactant-based remediation techniques have the potential to be very effective at removing DNAPLs from contaminated sites (e.g., [Pennell, et al., 1994 Baran, et al., 1994 Pennell, etal., 1997 Zimmerman, et al., 1999]). However, one risk associated with surfactant-based remediation of DNAPLs is the potential for unwanted... 

Kibbey, T. C. G. Ramsburg, C. A. Pennell, K. D. Hayes, K. F. Effects of Surfactant Properties on Equilibrium and Non-equilibrium Alcohol Partitioning into Dense Nonaqueous-Phase Liquids (DNAPLs) for In Situ Density Modification Applications, presented at the Fall American Geophysical Union national meeting, San Francisco, California, December, 1998. 

The contaminant s aqueous solubility and density greatly influence its final disposition in water-solid systems. Dense nonaqueous phase liquids (DNAPLs) are chemicals with densities greater than water and typically low aqueous solubilities. DNAPLs naturally partition away from the aqueous phase and towards the solid phase, often pooling on top of an impermeable solid layer. On the other hand, light nonaqueous phase liquids (LNAPLs) possess densities less than water and have a tendency to pool on the water s surface where they may be prone to volatilization and photolysis reactions. Various liquid-solid partition coefficients have been... 

TPH components have densities less than or close to that of water, these lighter nonaqueous phase liquids (LNAPLs) generally pose less potential for groundwater pollution than most chlorinated solvents (e.g., PCBs or TCE) that are denser than water (denser nonaqueous phase liquids [DNAPLs]). The nonaqueous phase liquid refers to liquids that are immiscible in water. Still, there are risks for shallow groundwater supplies, which may be used for private wells for drinking water purposes. 

Dense nonaqueous phase liquids (DNAPLs) are the chlorinated organic compounds that have a density higher than water. Because of this unique property, DNAPLs will pass through the vadose zone and contaminate groundwater. Some reside in... 

Recent studies have made it possible to classify water-organic solvent systems in CCC for separation of organic substances on the basis of the liquid-phase density difference, the solvent polarity, and other parameters from the point of view of stationary-phase retention in a CCC column [1,3-9]. Ito [1] classified some liquid systems as hydrophobic (such as heptane-water or chloroform-water), intermediate (chloroform-acetic acid-water and n-butanol-water) and hydrophilic (such as n-butanol-acetic acid-water) according to the hydrophobicity of the nonaqueous phase. Thirteen two-phase solvent systems were evaluated for relative polarity by using Reichardt s dye to measure solvachromatic shifts and using the solubility of index compounds [6]. 

The cost/performance factor of individual surfactants will always be considered in determining which surfactants are blended in a mixed active formulation. However, with the recent advent of compact powders and concentrated liquids, other factors, such as processing, density, powder flowability, water content, stabilization of additives, dispersibility in nonaqueous solvents, dispersion of builders, and liquid crystalline phase behavior, have become important in determining the selection of individual surfactants. 

U.S. 6770615 08/2004 Aouad et a/./Procter Gamble Nonaqueous liquid laundry detergent compositions with a suspended solid particulate phase comprised of low-density particles (binding agent, alkalinity source, a chelant, and builder or mixtures thereof). Ingredients that are insoluble in the... 

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