Suitability Of Coal Derived Solvents For Coal Liquefaction Processes

The suitability of a coal derived solvent anthracene oil, for coal liquefaction processes was studied. The experiments were conducted with a Spanish subbiturninous coal in a 250 ml stirred autoclave, using the following operating conditions: 1 hour reaction time, 17 //sup +/sub -// 1 MPa operating pressure, three temperatures (425, 450 and 475 /spl deg/C) and two solvent/coal ratios (2/1 and 3/1). The anthracene oil was tested both fresh and hydrogenated, and the results were compared with those obtained with tetralin, the archetypal hydrogen donor solvent. Different types of catalysts were used, which include red mud, Fe/sub 2/O/sub 3/ Aerosol and three Co-Mo alumina supported catalysts. The following conclusions were drawn from this study. 1) when no catalyst is used, the stronger the H-donor capacity of the solvent the higher the liquefaction yields obtained, 2) prehydrogenating the oil increases its H-donor capacity and consequently its efficiency as coal liquefaction solvent, 3) if the operating conditions used are not the appropriate ones anthracene oil itself can be partly converted to solid being definitely not suitable for coal liquefaction, 4) the addition of catalysts enhances enormously the behaviour of anthracene oil as liquefaction solvent, leading even to obtain higher coal conversions than with tetralin if very active catalysts are used, provided that the operating conditions are the appropriate ones.