Abstract:

The NaY/kaolin composite microspheres prepared by introducing two kinds of carbon black into the kaolin microspheres were characterized by XRD，low-temperature N₂ adsorption-desorption and SEM，and the modified catalysts were evaluated.The results showed that the relative crystallinity，mesopore volume and mesopore diameter of NaY/kaolin composite microspheres could be effectively improved by introducing carbon black.Compared with the conventional method，the relative crystallinity of the composite microspheres prepared by introducing 2%（mass fraction of carbon black in kaolin microspheres）N990 was increased from 26% to 30%，the volume of mesopores was increased from 0.212 cm³/g to 0.320 cm³/g，and the most probable pore size of mesopores was increased from 4.3 nm to 6.6 nm.The catalyst evaluation results showed that compared with the conventional method，the oil slurry yield was decreased by 2.44% and the total liquid yield was increased by 2.15% when the catalyst was prepared with 2% N990 adding.Compared with the carbon black model，the adding amount of carbon black had a greater impact on the mesoporous structure of the composite microspheres and the reaction performance of the catalyst.With the increase of carbon black content to 4%，the mesoporous volume of the composite microspheres was decreased，and the yield of catalyst slurry was increased.

Key words: Kaolin, Y-type molecular sieve, carbon black, in situ crystallization, FCC