CATALYTIC CRACKING OF ALKANES ON MCM-22 ZEOLITE - COMPARISON WITH ZSM-5 AND BETA-ZEOLITE AND ITS POSSIBILITY AS AN FCC CRACKING ADDITIVE

N-heptane cracking has been carried out on MCM-22, and its kinetic and decay behaviour is compared with that of ZSM-5 and Beta zeolites. In the case of MCM-22 cracking occurs in the 10-member ring channel syste m, as well as in the large cavities formed by 12-member rings. Product selectivities show that MCM-22, while presenting features which indic ate structural similarities with ZSM-5, it also presents characteristi cs corresponding to pores or cavities larger than ZSM-5. The selectivi ties to the individual products together with C-1 + C-2/iC(4), C-3/C-4 , C-5/C-2, iC(4)/total C-4, and alkane/alkene ratios indicate that MCM -22 has good properties to be used as an FCC octane booster additive s pecially valuable for the production of reformulated gasolines.