Abstract: Dual-solvent extraction of FCC slurry oil was performed with furfural as main solvent, n-octane as second solvent, the operation conditions, components of raffinate and its cracking performance were investigated. The optimal operation conditions were obtained as follows: extraction temperature in the range of 50～70 ℃; using 1st stage material mass ratios of m(furfural): m(slurry): m(n-octane)=2.0:1.0:1.5, 2nd stage of m(furfural): m(raffinate phase)=0.67:1.00, 3rd stage of m(furfural): m(raffinate phase)=1.20:1.00; the entire process involved 8 extraction steps (1st step as 1st stage, 2nd-4th steps as 2nd stage, 5th-8th steps as 3rd stage) with an additional solvent enrichment step added between the 4th and 5th step. Under such optimal extraction conditions, using FCC slurry oils from Sinopec Jiujiang Petrochemical Company and Sinopec Guangzhou Petrochemical Company as feed respectively, the mass fractions of saturated hydrocarbons in raffinates were 77% and 74%, respectively; the yields of saturated hydrocarbons reached 95.23% and 91.58%, respectively. The separation of saturated hydrocarbons from aromatics was successful, and the raffinate exhibited excellent cracking performance, it could be used as a high quality FCC feedstock.

Key words: FCC slurry, furfural, n-octane, extraction, saturated hydrocarbon