Date of Award


Document Type


Degree Name

Master of Science (MS)


Chemical Engineering


The effect of time at reaction temperature on the liquefaction of lignite using hydrogen or synthesis gas was studied. A slurry contain ing 200 grams of moisture-ash-free (MAF) lignite, 100 grams of water, and 400 grams of hydrogenated anthracene oil solvent was fed into the University of North Dakota Time-Sampling Hot-Charge Batch Autoclave System with the gas at an initial pressure of 400 psig.

Oil yields and conversions ranged from 0.9 percent to 35.7 percent and 66.7 percent to 90.6 percent, respectively, increasing as the time at or near the reaction temperature (380-420°C) increased. Higher con versions and greater oil and gas yields were obtained when using synthesis gas as compared to pure hydrogen. The increase in gas yield for the synthesis gas runs can be attributed to increased carbon dioxide production.