2-STAGE DIRECT COAL-GASIFICATION TO C-2-C-4 HYDROCARBONS

Results of a study conducted to convert coal to C-2-C-4 hydrocarbons i n a two-stage reactor system are presented. Coal was converted to liqu ids at 440 degrees C in a stirred batch autoclave using tetralin as th e hydrogen donor solvent. The liquids produced were separated from the unreacted coal and ash by filtration. The liquids were then fed into a second stage fixed bed reactor containing sulfided NiMo/Al2O3 and Si O2-Al2O3 catalyst. The liquids were hydrocracked on the dual-functiona l catalyst giving high yields of C-2-C-4 hydrocarbons. The pressure wa s 1800 psig and the temperatures were in the range of 425 to 500 degre es C. Reaction mechanisms of conversion of coal derived liquids to C-2 -C-4 hydrocarbons are presented. The kinetic parameters of the convers ion of coal liquids to gases were determined. The activation energy wa s determined to be 23.9 Kcal/mol. Cracking reactions involving C-C bon ds appear to be late-controlling.