Dissolution of subbituminous coal in tetrahydroquinoline

Abstract Two different samples of Wyodak subbituminous coal from the Powder River Basin in Wyoming were liquefied in a two dm 3 batch reactor using 1,2,3,4 tetrahydroquinoline, THQ, as a solvent. Sufficient sample was produced to determine product boiling ranges by distillation and to measure THQ distribution in the product. Product distillation showed that even at cyclohexane conversions greater than 50%, net distillate yields produced using THQ as a solvent were negative. In some cases, high boiling, coal-derived resid yields were greater than the dry coal charged to the reactor. These observations have been attributed to THQ losses resulting from dimerization of the THQ and reactions between THQ and coal derived components.