Selective Hydrocracking Polyaromatics into Light Aromatics: the Separation of Hydrogenation Center and Cracking Center

Serial combined catalysts with separated hydrogenation centers and cracking centers, which were composed of CoMo/Al2O3 and Ni/B, were synthesized and compared with the normal bifunctional catalysts of NiMo/Al2O3–Beta and CoMo/Al2O3–Beta. The properties of different catalysts were characterized by various methods. H2-TPR results demonstrated the existence of hydrogen spillover between a Co or Ni promoter, and Mo metals could facilitate the reducibility of oxide Mo species and hydrogenation of aromatics. The naphthalene hydrocracking performances were also evaluated and compared with different catalysts. The combined catalysts showed relatively high yields of light aromatics with high-octane values (