Research and development of rapid hydrogenation for coal conversion to synthetic motor fuels (Riser Cracking of Coal). First quarter report, April 1--June 30, 1977

Abstract

Fourteen runs were made in the bench-scale unit using system outlet pressures of 1500 and 2000 psig, coil outlet temperatures of from 1400/sup 0/ to 1500/sup 0/F, and solids levels in the feed stream of 88 percent and 67 percent by weight. In all runs, the solids residence time above 1300/sup 0/F was approximately 2 seconds. Several runs of 2-hours duration were made without difficulty, and sufficient hydrocarbon liquids were produced for detailed chemical analysis. The hydrogen feed was not superheated with respect to the coal in these runs, as it will be in the next series. The conversion levels were in the 40 to 50 percent range. The main products of the reaction system, particularly the hydrocarbon oils, have been characterized; maximum liquids production of just over 12 weight percent takes place at a coil outlet temperature between 1400 and 1500/sup 0/F. Upon distillation, about 45 percent of the main liquid product reports to the gasoline fraction, which upon analysis has been found to contain substantial amounts of benzene, toluene, xylene, and other high-octane blending stock constituents. Light gases are also produced that, on the hydrogen-free, carbon oxide-free basis, are approximately 70 mole percent methane, 20 mole percent ethane,more » and minor amounts of ethylene and propylene. The ethane is sufficiently abundant to warrant consideration of recovery of the ethane for use as a chemical feedstock.« less