Abstract: The effects of reaction temperature, reaction time and reaction pressure on the thermal conversion behavior of FCC-KQ aromatics-rich components of FCC slurry were investigated by means of optical microscopy, softening point, yield and thermogravimetric analysis, and the formation mechanism of mesophase pitch was proposed. The results indicated that the softening point increased slowly and the yield decreased rapidly at low temperatures or a short reaction time, while the softening point increased rapidly and the yield decreased slowly at high temperatures or a long reaction time. The growth and melting of mesophase spheres was a rapid process, in which the softening point of thermal polycondensation residues increased rapidly. The anisotropic mesophase pitch C120 with a softening point of 121 ℃ was produced from FCC-KQ at 390 ℃ and 2 MPa for 8 h. The properties of C120 pitch were similar to those of A240 pitch, with higher carbon residues and lower heteroatom content.

Key words: FCC slurry, aromatics-rich component, mesophase pitch, thermal conversion