The catalytic performance of Mo-based catalyst supported on HZSM-5 has been
studied in the absence of oxygen for methane dehydroaromatization in a fix
ed-bed continuous flow quarts reactor. The results showed that addition of
small amounts of gallium to Mo-H2SO4/HZSM-5 catalyst further improved the c
atalytic performance, and yields of C-2-C-11 hydrocarbons increased from 7.
84 to 8.96%. TPR proved that the addition of gallium was advantageous for t
he reduction of MoO3 on HZSM-5 zeolite. Meanwhile, the amount of coke forma
tion on Ga-Mo/HZSM-5 catalyst decreased gradually with increasing gallium c
ontents. TPO results suggested that the type of coke, such as active carbon
and inert carbon, deposited on Ga-Mo/HZSM-5 catalyst depends considerably
on time-on-stream. The more inert carbon war formed on the surface of catal
ysts with increasing time-on-stream. (C) 2001 Elsevier Science B.V. All rig
hts reserved.