Abstract: The effects of operation parameters, such as reaction temperature, weight hourly space velocity (WHSV) and catalyst to oil ratio (CTO) on the catalytic cracking of light distillate from Fischer-Tropsch synthesis were investigated using a laboratory fixed fluidized bed reactor. Test results indicated that with the increase of reaction temperature, CTO and the decrease of WHSV, the yields of dry gas, LPG and coke increased, and the yields of gasoline and diesel fuel decreased. The olefin content in gasoline fraction increased with the decrease of reaction temperature, CTO and WHSV. As the reaction temperature decreased, CTO and WHSV increased, the isoparaffin content in gasoline fraction increased. High reaction temperature and high CTO were in favor of the formation of aromatics in gasoline fraction, and the aromatics were mainly from the cyclization and dehydrogenation of small olefin molecules. When WHSV was low, the side chain cracking reactions of big alkyl aromatic molecules were promoted, yet without significant effect on hydrogen transfer reaction.

Key words: light distillate of Fischer-Tropsch synthesis oil, catalytic cracking, gasoline, aromatic hydrocarbon, olefin