Abstract: Coker gas oil contains relatively high concentrations of basic nitrogen compounds, polycyclic aromatic hydrocarbons, resins, and asphaltenes, which are unfavorable for catalytic cracking reactions. A certain refinery substituted coker gas oil with the raffinate obtained after furfural refining of coker gas oil,and blended it into the feed of catalytic cracking unit. This substitution led to a significant improvement in the properties of the feedstock. After furfural refining, the raffinate exhibited substantial reductions in the contents of basic nitrogen compounds, sulfur, resins, and aromatics, along with an increase in the content of saturated hydrocarbons. Following the blending of the raffinate, the product distribution of the catalytic cracking unit showed marked improvements. The yield of liquefied petroleum gas increased by 0.93 percentage points, gasoline yield by 1.08 percentage points, and total liquid yield by 0.30 percentage points, while the yields of coke, slurry oil, and diesel decreased. The volume ratio of hydrogen to methane in the dry gas decreased, indicating enhanced hydrogen utilization efficiency during catalytic cracking. The propylene content in liquefied petroleum gas has slightly increased. The octane number of gasoline increased, and the contents of NO_x and SO₂ in the flue gas both decreased. Catalyst consumption reduced by 0.3 kg/t, resulting in annual savings of 3.5 million Yuan in catalyst costs.

Key words: catalytic cracking, coker gas oil, furfural refining, raffinate