Abstract: Based on the accumulation in the continuous development and application of petroleum refining technology for more than 20 years, the FCC process and series catalysts for directional control of gasoline composition have been developed, and the technology route of olefin reduction and desulfurization has been integrated successively, which can provide the most economical solution for the continuous upgrading of vehicle gasoline quality in China. The mechanism and method of selective control of bimolecular reaction and optimization of reaction depth by negative hydrogen ion transfer were put forward. By analyzing all factors affecting conversion and type of hydrogen transfer reaction, and basing on the catalytic reaction engineering of variable diameter fluidized bed and special catalysts, a FCC process with directional control of gasoline composition has been developed, which can flexibly adjust gasoline composition. The volume fraction of olefins is reduced to 8.5%, and the iso-alkanes are distributed in the light end of gasoline, which is conducive to the increase of octane number and the decrease of 50% distillation temperature of gasoline. In the process of catalytic cracking, the content of isoalkanes and isoalkenes in gasoline should be increased as much as possible, and the saturation of olefins in gasoline should be reduced as much as possible to reduce the loss of octane number.

Key words: vehicle gasoline, catalytic cracking, adsorptive desulfurization, olefins, isoalkanes, octane number