REACTIONS OF META-XYLENE ON ZEOLITES WITH INTERSECTING MEDIUM AND LARGE PORES .1. BASIC STUDIES

The reactions of m-xylene are conducted over all known zeolites with i ntersecting medium and large pores (MCM-22, NU-87, CIT-1, SSZ-33, SSZ- 26) and the results compared to those from large (SSZ-24, ZSM-12, zeol ite beta, zeolite L) and medium (ZSM-5, EU-1) pore zeolites. Each of t he materials MCM-22, NU-87 and CIT-1/SSZ-33/SSZ-26 reveals unique reac tion behavior in terms of the p-xylene/o-xylene and isomerization/disp roportionation ratios, the distribution of formed trimethylbenzenes an d the rate of deactivation. The reaction activities and selectivities of MCM-22 and CIT-1/SSZ-33/SSZ-26 are somewhat like medium and large p ore zeolites, respectively, as is expected from their crystal structur es. NU-87 displays a lower p-xylene/o-xylene ratio and a higher turnov er frequency than predicted from the crystal structure.