| 초록 |
Cracking is a popular process to produce economically value-added products as middle distillates from vacuum residue. In this study, NiK/CeO2, NiK/CeZrO2, and NiK/CeZrO2-Al2O3 catalysts were synthesized by adding Ni and K into CeO2, CeZrO2 and CeZrO2-Al2O3 supports which possess high oxygen capacity and self-redox ability. These catalysts were used for cracking process of vacuum residue over steam at 500oC in fixed-bed reactor system. In the reaction results, high amount of light oils including naphtha, diesel and VGO were produced through oxidative cracking and catalytic cracking on active sites over the supports; and the quality of liquid products was significantly improved by hydrogenation over nickel metallic sites. Moreover, steam decomposition occurring over the supports provided an alternative hydrogen source for hydrogenation and oxygen source for oxidative cracking. |
