Rapid liquefaction of Longkou lignite coal by using a tubular reactor under methane atmosphere

Rapid liquefaction of Longkou lignite coal under methane atmosphere was studied in a novel laboratory scale tubular reactor. Experiments were performed at a temperature ranging from 400 to 800 degrees C, a residence time ranging from 4.5 to 11.2 s and 10-15 MPa, (without catalyst). Reactions were also carried out under a nitrogen gas atmosphere at the same reaction conditions. The results indicate that there are synergistic effects between coal and methane at temperatures higher than 600 degrees C, and the temperature and residence time are the main factors influencing the coal conversion and products distribution. The oil yields reach a maximum of 21.97 (wt.% daf) at 750 degrees C during 9.0 s. (C) 2008 Elsevier Ltd. All rights reserved.