Abstract: Composite molecular sieve MCM-41-HY having mesoporous and microporous pore structure was prepared by hydrothermal method and the structure of the composite molecular sieve was characterized. A MY-1 catalyst was prepared using said synthesized composite sample as the main cracking component, nickel and tungsten was impregnated. The catalytic performance of MY-1 catalyst was studied on a 200 ml fixed-bed hydrogenation unit using Daqing VGO as feedstock. The results showed that with a 75% conversion of the feedstock over 350℃ fraction, the C5+ liquid yield was 98.89%, the yields of diesel fraction (138-370℃) was 68.7% and the selectivity of middle distillates was 83.21%.

Key words: composite molecular sieve, hydrocracking, catalytic performance, middle distillate selectivity