Several transition-metal complexes were tested for their effectiveness in liquefying coal under very mild conditions, Liquefaction was not observed, probably because interaction with the coal deactivates the catalyst.
The most active hydrogenation catalysts known are soluble 20 ml of solvent [tetrahydrofuran (THF), dimethylformacomplexes of transition metals. A variety of complexes, mide (DMF), or 95% ethanol], and heating to 25-170Β°C particularly several of rhodium, have demonstrated that under a hydrogen pressure of 0.1-3.96 MPa gauge (14aromatic molecules can be hydrogenated under very mild 575 psig) for 5-24 h. After this reaction period, the temconditions'-'j. For example, the N-phenylanthranilic acid perature was lowered to ambient and the pressure released. complex of rhodium (I) readily hydrogenates benzene at Suction filtration was followed by washing with 50 ml of room temperature and 1 atm of hydrogen'-4. Hydrogenoly-tetrahydrofuran. The solid was dried, and the filtrate evasis has also been demonstrated in very mild conditions'. In porated to obtain the solvent-soluble residue. The catalysts view of the striking activities of several soluble transition-were either. synthesized or were obtained from the Ventron metal complexes, and the resistance of homogeneous cata-Corporation and utilized without further purification. The lysts to poisoning, we sought to evaluate the effectiveness of coal was mined at the Fries Mine, Island Creek Coal Comseveral compfexes in liquefying coal under very mild conditions. pany, Kentucky (No.1 1 bituminous: C 75.4, H 6.2 wt % daff.