Dynamic behaviour of Ni-containing catalysts during partial oxidation of methane to synthesis gas

Complex dynamic phenomena—oscillations and temperature waves—are observed during partial oxidation of methane to synthesis gas over Ni-containing metal catalysts (Ni metal foam and chromel–alumel thermocouple). Kinetic analysis of oscillatory process shows that a substantial amount of oxygen and carbon is stored and evolved by catalysts during the cycle. A sharp splash of activity is observed when amounts of stored oxygen and carbon are minimal. It was concluded that the oscillatory behaviour could be due to a difference in the activities of C- and O-covered and clean metal. A “direct” mechanism of CO and H2 formation without intermediate total oxidation is more probable than a “sequential” one.