Thermochemical and vapor pressure behavior of anthracene and brominated anthracene mixtures

Abstract

The present work concerns the thermochemical and vapor pressure behavior of the anthracene (1)+2-bromoanthracene (2) and anthracene (1)+9-bromoanthracene (3) systems. Solid–liquid equilibrium temperature and differential scanning calorimetry studies indicate the existence of a minimum melting solid state near an equilibrium temperature of 477.65K at x1=0.74 for the (1)+(2) system. Additionally, solid–vapor equilibrium studies for the (1)+(2) system show that the vapor pressure of the mixtures depends on composition, but does not follow ideal Raoult's law behavior. The (1)+(3) system behaves differently from the (1)+(2) system. The (1)+(3) system has a solid solution like phase diagram. The system consists of two phases, an anthracene like phase and a 9-bromoanthracene like phase, while (1)+(2) mixtures only form a single phase. Moreover, experimental studies of the two systems suggest that the (1)+(2) system is in a thermodynamically lower energy state than the (1)+(3) system.