Formation of Solid Solution and Ternary Phase Diagrams of Anthracene and Phenanthrene in Different Organic Solvents

Crash cooling crystallization of different anthracene (ANT) and phenanthrene (PHE) mixtures in toluene, xylene, and N,N-dimethylformamide (DMF) was investigated. The crystals obtained were identified by powder X-ray diffraction, differential scanning calorimetry, and high-performance liquid chromatography. To verify the formation of different solid solutions, ternary phase diagrams of ANT and PHE in toluene, xylene, and DMF at 308.15 K and 0.1 MPa were determined through experiments. Two solid solutions, α and β, respectively, formed at PHE-rich and ANT-rich ends but coexisted in the middle section of the composition. The effect of solvent and separation process optimization of ANT and PHE were further investigated based on the ternary phase diagrams.