| 摘要 |
A catalytic cracking catalyst and process are disclosed using a catalyst containing: a matrix, a large pore molecular sieve, a shape selective paraffin cracking/isomerization zeolite and a shape selective aliphatic aromatization zeolite. An exemplary catalyst comprises dealuminized zeolite Y, optionally containing rare earth elements, HZSM-5, and gallium ZSM-5 in a matrix. The matrix contains and protects the relatively fragile zeolite components and acts as a sodium and metals sink. The large pore molecular sieve cracks large hydrocarbons to lighter paraffins and olefins. The shape selective paraffin cracking/isomerization component cracks/isomerizes the paraffins produced by the large pore molecular seive. The shape selective aliphatic aromatization catalyst converts light paraffins and olefins into aromatics. A single shape selective zeolite, e.g., ZSM-5 with a controlled amount of an aromatization component such as gallium, may promote both paraffin cracking/isomerization and aromatization.
|
