Abstract: The effects of the mass ratio of catalyst to oil and the total acid content of catalyst on the conversion and nitrogen distribution of Daqing VGO and its mixture with quinoline were investigated respectively at 500-560 ℃ in a fixed fluidized bed reactor. The results show that quinoline exhibits an adverse influence to the reactivity of Daqing VGO, resulting in more nitrogen in gasoline and diesel than the single VGO feed. Alkylation and cracking reactions are the main pathways of quinoline during catalytic cracking. Aniline, as the middle product, can further crack into ammonia with the increase of temperature. The competitive adsorption of basic compounds can be weakened by raising mass ratio of catalyst to oil, resulting in decrease of nitrogen content in liquid products. The conversion of quinoline is significantly enhanced as the catalyst total acid content increases and more nitrogen is concentrated in coke.

Key words: basic nitrogen compound, catalytic cracking, quinoline, nitrogen distribution