Direct decomposition of methane to hydrogen on metal-loaded zeolite catalyst

The regeneration of a Ru-Mo/ZSM5 catalyst used to produce hydrogen by decomposition reactions was examined at 873 K in either flowing hydrogen or air. The Ru-Mo/ZSM5 catalyst was deactivated under methane decomposition reaction conditions at temperatures of 873, 973, and 1073 K. The effect of reaction and regeneration conditions on catalyst activity, BET surface area and temperature programmed oxidation profiles is discussed. Regeneration using hydrogen was found to be less effective than air oxidation for the conditions explored. The methane decomposition reactions produced hydrogen primarily through the formation of liquid aromatics. The highest hydrogen production rates were obtained at 1073 K, however, deactivation was greatest at this temperature and the catalyst was not fully regenerated. A better selectivity to liquids combined with a relatively stable catalyst activity indicates that 973 K may be adequate for longer term catalyst and cycled regeneration analyses.