Phenanthrene vapor pressure

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

FIGURE 4.1.1.23.2 Logarithm of vapor pressure versus reciprocal temperature for phenanthrene. 

Nelson, O.A., Senseman, C.E. (1922) Vapor pressure determinations on naphthalene, anthracene, phenanthrene, and anthraquinone between their melting and boiling points. Ind. Eng. Chem. 14, 58-62. 

Wieczorek, S.A., Kobayashi, R. (1981) Vapor pressure measurements of 1-methylnaphthalene, 2-methylnaphthalene, and 9.10-dehydro-phenanthrene at elevated temperatures. J. Chem. Eng. Data 26, 8-11. 

FIGURE 9.63 Plots of om-phase-normalized gas-particle partitioning constant log Kp iun vs logarithm of the subcooled liquid vapor pressure, log pL, for a series of semivolatile PAHs partitioning on ( ) dioctyl phthalate (DOP) or (a) secondary organic aerosol (SOA) from photooxidized gasoline vapor. PAHs are as follows naphthalene, A acenaphthalene, B fluorene, C and C phenanthrene, D and D anthracene, E and E fluoranthene, F and F pyrene, G and G chrysene, H (adapted from Liang el al., 1997). 

TABLE 10.9 Calculated Effectof Vapor Pressure and Aerosol Concentration on the Percentage in the Aerosol Phase of Phenanthrene, Pyrene, and Benzo[a]pyrene ... 

The two isomeric polycyclic aromatic hydrocarbons phenanthrene and anthracene are solids at 25°C. Although these compounds have almost the same boiling point (see below), their vapor pressures at 25°C differ by more than one order of magnitude (see Appendix C). Explain these findings. What differences would you expect for the subcooled liquid vapor pressures of the two compounds at 25°C ... 

Figure 9.4 Physicochemical properties of anthracene and phenanthrene according to the PHYSPROP database [14]. The large discrepancy in MP of both these compounds, AMP = 115°C, explains their differences in aqueous solubility and vapor pressures. The difference in solubility of molecules calculated using GSE (equation 9.3) Alog.S = 0.01 115 = 1.15 approximately corresponds to the experimentally observed value AlogN = 1.42.

A number of studies have explored ways in which partial vapor pressures may be obtained using TGA data, thereby allowing both prediction of vapor pressure under a range of circumstances and calculation of the constants associated with the approaches described previously. In particular, Price and Hawkins (12) have argued that the rate of mass loss for vaporization and sublimation within a TGA should be a zero-order process, and hence should be constant for any given temperature, subject to the important condition that the available surface area also remains constant. This means that the value of v from Equation 6.4 should be easily calculated from the TGA data. If one performs this experiment for materials with known vapor pressure and temperature relationships (the authors used discs of acetamide, benzoic acid, benzophenone, and phenanthrene), then the constant k for the given set of TGA experimental conditions may be found. Once this parameter is known, the vapor pressure may be assessed for an unknown material in the same manner. 

It is obvious from the similarity of the vapor pressures of these three compounds, phenanthrene, carbazole, and anthracene, tliat it is practically impossible to separate them completely by any process of distillation. That a considerable degree of separation may be effected, however, by volatilization in a stream of air followed by fractional condensation in a series of... 

Isomer effects cannot be predicted. This means the same activity coefficients are obtained, for example, for o-/m-/p-xylene or phenanthrene/anthracene with the different solvents. But at least in the case of VLE or SLE calculation this is not a great problem, since the required standard fugacities, that is, vapor pressure, melting point, and heat of fusion are of much greater importance than small differences of the activity coefficients. Similar problems are also observed for other predictive models, for example, the quantum chemical approach. 

P8.14 The vapor pressures of liquid anthracene and phenanthrene can be described by the Antoine equation using the Antoine parameters given below. Calculate the vapor-liquid-solid equilibrium (VLSE) along the solid-liquid saturation curve assuming ideal mixture behavior in the liquid phase. Melting points and heats of fusion of both components are given in example P8.1 above. Compare the vapor-liquid separation factors to those of an isothermal VLE data set at 220 "C (calculate assuming ideal liquid mixture behavior). 

Roper, V. Kohayashi, R. Apparatus and procedure to measure binary total pressure at high temperature fluorene - phenanthrene vapor-liquid equilibria and data reduction by the four-suffix Margules model to obtain infinite-dilution activity coefficients Fluid Phase Equilib. 1989,47, 273-293... 

It is also observed that the presence of the nonvolatile solute like phenanthrene has negligible effect on the vapor phase mole fractions of toluene and CO2, inasmuch as the latter for the ternary system are very much close to those for the binary (toluene and CO2) system at the same pressure and 298 K (60). The P-T trace for the constant liquid phase compositions at the S-L-V equilibrium is obtained from the isothermal plots of P vs (X3/I — X3) at three temperatures (Figure 28). It can be seen that the pressure required for attaining the S-L-V equilibrium increases with temperature at the same composition and increases with V3 at constant temperature. This trend is similar to that reported by Kikic et al. (41). Figure 29 depicts the effects of variations in pressure and temperature on isothermal and isobaric triangular... 

Hutchenson, K. W., J. R. Roebers, and M. C. Thies. 1990. Vapor-liquid equilibrium for phenanthrene-toluene mixtures at elevated temperatures and pressures. J. Fluid Phase Equil. 60 309-317. 

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