COAL-LIQUEFACTION WITH ANTHRACENE OIL - INFLUENCE OF SOLVENT PRETREATMENT, TEMPERATURE, CATALYST AND PRESSURE

The effect of solvent pretreatment, temperature, a CoMo/Al2O3 catalyst and pressure on coal liquefaction with anthracene oil has been evaluated. The experiments were conducted in a 500 ml autoclave with 10 g of a Spanish subbituminous A coal, 30 g of solvent, 1 hour reaction time and 400 rpm stirring speed. The liquefaction products were fractionated into oils, asphaltenes and preasphaltenes using pentane, toluene and THF as extractive solvents. The behaviour of anthracene oil as coal liquefaction solvent is very much enhanced by prehydrogenating it and by the addition of an active catalyst. The influence of temperature depends on the operating conditions such as solvent pretreatment, catalyst, pressure etc. The addition of an active catalyst greatly improves conversion and the quality of the liquefaction products and diminishes repolimerization reactions. Hydrogen pressure is essential for coal liquefaction with anthracene oil. although over 16 MPa no further increase in coal conversion is observed.