Abstract:

Using Al-SBA-15/USY composite molecular sieves as main components,different catalysts were prepared by leach- ing method and kneading method.The catalyst was characterized by transmission electron microscopy（TEM）,temperature program reduction（H₂-TPR）,temperature programmed desorption of ammonia（NH₃-TPD） and nitrogen absorption/desorption. The results showed that the catalyst had microporous-mesoporous pores,and the pore volume of the catalyst prepared by leaching method reached 0.34 mL/g,the pore diameter reached 5.5 nm and the acid content reached 0.265 mmol/g,which was all higher than that of the catalyst prepared by kneading method.The catalyst was evaluated on a 200 mL evaluation apparatus using reduced pressure wax oil（VGO） as a raw material. The results showed that the middle distillate yield of the catalyst prepared by leaching method was increased by 1.6% and the selectivity was increased by 1.9% compared with the catalyst prepared by the kneading method.

Key words: Al-SBA-15/USY composite molecular sieve, metal loading method, hydrogen cracking catalyst