Phenanthrene coefficient

Dewar and Mole236 derived second-order rate coefficients for chlorination at 25 °C of benzene (6xl0-7), diphenyl (6.9 xlO-4), naphthalene (6.3 xlO-2), phenanthrene (2.9xl0 1) and triphenylene (2.2xlO-2) in Analar acetic acid and of diphenyl (9 x 10-7), naphthalene (1.9 x 10-4), phenanthrene (1.3 x 10-3),... 

Reported vapor pressures of phenanthrene at various temperatures and the coefficients for the vapor pressure ... 

Reported Henry s law constants and octanol-air partition coefficients of phenanthrene at various temperatures and temperature dependence equations... 

Hegeman, W.J.M., van der Weijden, C.H., Loch, J.P.G. (1995) Sorption of benzo[a]pyrene and phenanthrene on suspended harbor sediment as a function of suspended sediment concentration and salinity A laboratory study using the cosolvent partition coefficient. Environ. Sci. Technol. 29, 363-371. 

A set of n = 209 polycyclic aromatic compounds (PAC) was used in this example. The chemical structures have been drawn manually by a structure editor software approximate 3D-structures including all H-atoms have been made by software Corina (Corina 2004), and software Dragon, version 5.3 (Dragon 2004), has been applied to compute 1630 molecular descriptors. These descriptors cover a great diversity of chemical structures and therefore many descriptors are irrelevant for a selected class of compounds as the PACs in this example. By a simple variable selection, descriptors which are constant or almost constant (all but a maximum of five values constant), and descriptors with a correlation coefficient >0.95 to another descriptor have been eliminated. The resulting m = 467 descriptors have been used as x-variables. The y-variable to be modeled is the Lee retention index (Lee et al. 1979) which is based on the reference values 200, 300, 400, and 500 for the compounds naphthalene, phenanthrene, chrysene, and picene, respectively. 

Figure 3.3 SPMD-water partition coefficients (ml mL units) as a function of log Kqw for PAHs—filled circles Huckins et al. (1999), filled triangles Huckins et al. (2004) phenanthrene, PCB 52, and p,p -DDE—open triangles Huckins et al. (2002a) chlorobenzenes, PAHs, and PCBs—squares Booij et al. (2003a) pesticides—filled diamonds Sabaliunas and Sodergren (1997) and HCHs—open diamonds Vrana and Schiiurmann (2002). Additional kjw data were calculated for PCBs (asterisks) and alkylated benzenes (crosses) using the fCmw data from Lefkovitz et al. (1996) and Reynolds et al. (1990), and the data from Chiou (1985).

Murillo et al. (2004) studied the adsorption of phenanthrene (polycyclic aromatic hydrocarbon -PAH) from helium as carrier gas on a coke fixed-bed adsorber, at 150 °C. The isotherm of the phenanthrene-coke system at 150 °C was found to be of Freundlich type with Fr = 0.161 and KF = 1.9 (mol/kg)(m3/mol)0161. The isotherm has been derived for phenanthrene concentrations between 1.71 X 10 4 and 1.35 X 10-2 mol/m3. Finally, the average solid-phase diffusion coefficient, calculated from several experimental runs, was found to be 6.77 X 10-8 cm2/s. 

Fig. 25. Comparison between the excitation spectrum of the rhodamine sensitized current Jyi in phenanthrene (dye coverage 0 = 0.4 for 10-e M rhodamine in aqueous solution at pH = 7) with the absorption coefficient Cmonomer of the rhodamine monomer in aqueous solution at pH = 7...

Estimate the solubility and the activity coefficient of phenanthrene in (a) seawater at 25°C and 30%o salinity, and (b) a salt solution containing 117 g NaCl per liter water. 

At 25°C phenanthrene is a solid. Because the free energy contributions of phase change (i.e., melting, or condensation in the case of a gas) to the overall free energy of solution are not affected by salts in the solution, it is the aqueous activity coefficient that is increased as salt concentration increases (Eq. 5-28). Hence, the actual solubility decreases by the same factor (Eq. 5-27). The Kf value of phenanthrene is 0.30 M 1 (Table 5.7). Since 34.2%o salinity corresponds to a total salt concentration of 0.5 M (see text), [salt]tot for 30%o is equal to 0.44 M. Insertion of these values into Eq. 5-28 yields ... 

For times shorter than this, the rate coefficient may be expected to be time-dependent. For instance, with A 108 s 1, L 0.14 nm and D 10"18 m2 s 1, Reff 1 nm and > 0.3 s. This would require a long-lived phosphorescent state, such as of phenanthrene (r0 4 s), for time dependence to be observed. Since the residual time dependence of eqn. (96) contains no dependence on the radial co-ordinate, r, the time-dependent rate coefficient, eqns. (73)—(75), is simply... 

Little attention has so far been paid to studying exchange energy-transfer processes in media so viscous that a steady-state is no longer established. Butler and Pilling [200] specifically sought experimental evidence for time-dependent rate coefficients of the form of eqn. (98). They chose to study triplet phenanthrene in methanol—water mixtures and used cupric chloride as the acceptor since it is readily soluble and a very efficient quencher of triplet phenanthrene. To observe even the t 1/2 dependence of the time-dependent rate coefficient, concentrations [A] > 10-2 are required that is with Re 1 nm and [A] > 10 mmol... 

Estimates of the effective encounter distance, f eff, and diffusion coefficient, D, from quenching of triplet phenanthrene by cupric ions in methanol—water mixtures (Butler and Pilling [200])... 

Thermochemical data are available (Ref 2) on the heats of combustion and formation for all five isomers, on the heats of nitration from various Dinitrotoluenes for the 23,4-, 2,4,5-, and 2,3,6-isomers, and on the heats of crystn for the 2,3,4- and 2,4,5-isomers. Data are also available (Ref 1) on the shock sensitivities of all of the isomers except 2,3,6-, and on the rates of decompn at 140° of the 23,4-, 2,4,5-, and 23,5-isomers. The detonation pressure and the temp coefficient of decompn between 140 and 180° have been measured for the 2,4,5-isomer 2,3,4- and 2,4,5-TNT form addition compds ( 7r-complexes ) at 1 1 molar ratio with several polycyclic aromatic hydrocarbons (naphthalene, acenaphthene, fluorene, phenanthrene and anthracene) (Ref 2). 2,4,5-TNT forms complexes with 4-aminozaobenzene, 4-aminoacetophenone, bis (2 hydroxy ethyl) amine, and tris (2-hydroxy-ethyl) amine (Ref 1). The first two have a 1 1 molar ratio, the third 1 2, and the fourth 2 1. Upon heating, the two 4-amino compds react with replacement of the 5-nitro group, as discussed below... 

Micellar partition coefficient (Kmic) values for phenanthrene and naphthalene below their aqueous solubility limits were determined from experimental fluorescence measurements using nonlinear regression analysis of the following equation ... 

An increase in the phenanthrene partition coefficient for SDS micelles is observed with increasing ionic strength at a fixed pH of 6 (Table 2). A conceptual model has been proposed to describe the effects of electrolyte addition on the partitioning of nonpolar compounds such as phenanthrene into the core (or deep region within the palisade layer) of ionic surfactant... 

Table 2. Surfactant critical micelle concentrations (CMC) and micellar partition coefficients (Kmu) for phenanthrene under various solution chemisty conditions.a ... 

Figure 4 shows phenanthrene and naphthalene sorption isotherms to kaolinite covered with varying levels of sorbed surfactant these levels of surfactant coverage correspond to the different regions existing in the surfactant sorption isotherms discussed earlier (Fig. 1). The linearity of each isotherm was evaluated using Freundlich and linear sorption models. It is apparent from Fig. 4 and Table 4 that HOC partitioning to kaolinite with and without adsorbed surfactants results in linear or near-linear isotherms. As the amount of surfactant adsorbed on the kaolinite surface increased, the sorption of phenanthrene and naphthalene to the solid phase also increased. However, upon normalizing by the amount of sorbed surfactant present, the sorbed surfactant partition coefficient (Kss) decreased with increasing sorbed surfactant amounts (Table 4).

Table 5. Phenanthrene distribution (Kn) and organic carbon normalized partition (Km) coefficients to sorbed surfactants on kaolinite for varying solution chemistry conditions.a... 

Figure 7. Effect of pH on phenanthrene distribution (A. 0) and organic carbon normalized partition (/ ) coefficients for sorbed SDS, The ionic strength was 0.1 M NaCl, and the kaolinite concentration was 100 g/L. Error bars for some data points are smaller than the symbols. The solid line is the average Kx value for pH values above the PZC of kaolinite, The predicted value is based on an equation from Schwarzenbach et al. (1993), Adapted from Ko et al. (1998a).

Depending on the desired treatment methodology and goals, addition of surfactants to a subsurface system should either increase HOC distribution coefficients (i.e., immobilization approach) or decrease them (i.e., mobilization objective as in many SEAR applications). For example, distribution coefficients for phenanthrene and naphthalene to kaoiinite are 0.002 and 0.0003 L/g, respectively (Table 4). Therefore, if enhanced mobilization of these HOCs in a similar type of aquifer system was desired, addition of a surfactant would have to bring the distribution coefficients below these values. However, as can be seen in Fig. 5, all distribution coefficients for the surfactant doses investigated here are larger than these values, even when the doses and subsequent aqueous surfactant concentrations are well above the CMC. This observation results from a combination of surfactant sorption followed by HOC partitioning to the sorbed surfactant. 

Ortiz, et. al (1999) measured overall mass transfer coefficients for the aqueous dissolution of naphthalene, pyrene, and phenanthrene from oils ranging in viscosities from a light lubricating oil (86 cp) to a high viscosity oil ( 1000cp). These measurements were performed in continuous-flow systems for time periods ranging from several months up to one year. The authors hypothesize that naphthalene, pyrene, and phenanthrene dissolution from a high viscosity oil (1000 cp) results in a depleted zone within the NAPL that increases with dissolution time. 

Bonin, J. L., and Simpson, M. J. (2007). Variation in phenanthrene sorption coefficients with soil organic matter fractionation The result of structure or conformation Environ. Sci. Technol. 41,153-159. 

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