Abstract: Needle coke was prepared by two-stage coking from aromatic fraction of paraffin-based catalytic cracking slurry (FCCDO) with the addition of different naphthalene compounds (naphthalene, 1-methylnaphthalene, tetrahydronaphthalene and decahydronaphthalene). The influence of naphthalenes on the composition and the properties of needle coke was investigated by elemental analysis, FT-IR and group composition, etc. The results showed that the addition of small molecular aromatics promoted the formation of carbonaceous mesophase with the increasing of naphthalene content. Aromatics with alkyl chains could improve the carbonization activity of the system through free radical and hydrogen transfer reactions, which could effectively increase the condensation degree of the products. At the same time, the aromatics with naphthenic structure could also change the rheological properties of the system through ring-opening reaction and hydrogen transfer reaction, and reduce the viscosity of the system, thus reducing the condensation degree of the product.

Key words: catalytic cracking slurry, aromatic enriched fraction, naphthalene compounds, needle coke, carbonaceous mesophase