Net hydrogen as a correlative parameter in non- catalytic liquefaction of American coals

摘要

Net hydrogen represents the H content per 100 grams of C, corrected for H equivalents of O, N, and S. We have examined liquefaction of a variety of coals, lignite through high-volatile bituminous, in microautoclaves at 300-450°C, cold H_2 pressure of 7 MPa, and times to 1 h. Model compounds were used as solvents. In reactions without catalyst, net H helps correlate conversions and evaluate effects of temperature, residence time, and solvent. Plots of conversion vs. net H at various temperatures suggest that the increase in conversion from increased temperature is about the same for coals with net H of 3-6%. A 60-min. reaction at 425°C provides better conversion than 30 min. at 450°C, the difference being increasingly marked for coals of higher net H. At 350-360°C, conversions in pyrene and phenanthrene are nearly identical, suggesting that H-shuttling by pyrene is not effective at these temperatures. Mineral matter has no catalytic effect at low reaction temperatures.