Article

Thermodynamic study of (anthracene + benzo[a]pyrene) solid mixtures.

Brown University Division of Engineering, 182 Hope Street Box D, Providence, RI USA 02912, 401-863-2775 (p) 401-863-9120 (f).
The Journal of Chemical Thermodynamics (Impact Factor: 2.42). 11/2010; 42(11):1356-1360. DOI: 10.1016/j.jct.2010.05.019
Source: PubMed

ABSTRACT To characterize better the thermodynamic behavior of a binary polycyclic aromatic hydrocarbon mixture, thermochemical and vapor pressure experiments were used to examine the phase behavior of the {anthracene (1) + benzo[a]pyrene (2)} system. A solid-liquid phase diagram was mapped for the mixture. A eutectic point occurs at x(1) = 0.26. The eutectic mixture is an amorphous solid that lacks organized crystal structure and melts between T = (414 and 420) K. For mixtures that contain 0.10 < x(1) < 0.90, the enthalpy of fusion is dominated by that of the eutectic. Solid-vapor equilibrium studies show that mixtures of anthracene and benzo[a]pyrene at x(1) < 0.10 sublime at the vapor pressure of pure benzo[a]pyrene. These results suggest that the solid-vapor equilibrium of benzo[a]pyrene is not significantly influenced by moderate levels of anthracene in the crystal structure.

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