Aromatization of methane in the absence of oxygen over Mo-based catalysts supported on different types of zeolites

Zhang, CL Li, SA Yuan, Y Zhang, WX Wu, TH Lin, LW

Cl. Zhang et al., Aromatization of methane in the absence of oxygen over Mo-based catalysts supported on different types of zeolites, CATAL LETT, 56(4), 1998, pp. 207-213

21

INGLESE

Article

Physical Chemistry/Chemical Physics","Chemical Engineering

CATALYSIS LETTERS

1011-372X → ACNP

56

4

1998

207 - 213

ISI

1011-372X(1998)56:4<207:AOMITA>2.0.ZU;2-Q

The catalytic performance of Mo-based catalysts supported on various zeolit es has been studied for methane aromatization in the absence of oxygen in a fixed-bed continuous-flow quartz reactor, and their catalytic properties a re correlated with features of zeolite structure. It was found that H-type silica-alumina zeolites, such as ZSM-5, ZSM-8, ZSM-11 and beta possessing t wo-dimensional structure and pore diameter equaling the dynamic diameter of a benzene molecule (about 6 Angstrom) simultaneously, are fine supports fo r methane activation and aromatization catalysts. Among them, MoO3/H-ZSM-11 has the best activity and stability; for instance, a methane conversion of 8.0% and selectivity higher than 90% was obtained at 973 K. The catalytic performance of MoO3/H-ZSM-8 is somewhat lower than that of MoO3/H-ZSM-5, wh ile activity of MoO3/H-beta is lower than that of MoO3/H-ZSM-8. Catalysts s upported on H-MCM-41 and H-SAPO-34 exhibit low activity for methane aromati zation and those supported on H-MOR, H-X and H-Y give only a little amount of ethylene. Over MoO3/H-SAPO-5 and MoO3/H-SAPO-11 no hydrocarbons were det ected.