Thermal Dissolution of Different-Ranked Coals in Tetralin and the Anthracene Fraction of Coking Tar

The characteristics of the thermal dissolution of coals of different degrees of metamorphism in the hydrogen-donor solvent tetralin and the anthracene fraction of coal coking tar are compared. It was established that, at 380°C, the dependence of the activity of coal on the metamorphic stage has an extremum. In the tetralin solvent, low-rank coals of grades D and G with a loose supramolecular structure and a high concentration of aliphatic fragments exhibited a maximum activity. The resulting product was a viscous flowing mass. In the liquid-phase anthracene fraction, medium-rank coking coals of grades GZh and Zh containing an increased amount of close-packed polycondensed aromatic molecules, were highly active. The process proceeded selectively with the formation of plastic pitch-like products with softening temperatures from 76 to 96°C with little formation of gases and distillate fractions.