STUDY ON INFLUENCE OF ZEOLITE PORE STRUCTURES ON CATALYTIC CRACKING OF N-HEXANE

Abstract

Abstract: Catalytic cracking of n-hexane was conducted in a fixed-bed reactor on four zeolites with different pore structures. The results show that pore structures of zeolites play significant roles in product distribution and deactivation of catalyst due to carbon deposition and that the smaller the pore size of the zeolite, the more conducive to the monomolecular cracking, the higher the selectivity of ethylene and propylene, due to a suppression of the hydrogen transfer reaction. The highest initial selectivity of ethylene and propene are gained on ZSM-35, but it is rapidly inactivated, while the ZSM-5 exhibits better selectivity (ethylene and propylene of 45.06%) and anti-carbon deposition ability among these zeolites. The reduction of conversion is only about 4% after 4 h.

Key words: pore structure, hexane, catalytic cracking, light olefin

CLC Number:

References

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