Facing the catalytic combustion of CH4/H2 mixtures into monoliths

Depending on the thermal conductivity of the tested monoliths, the existence of the steady-state multiplicity was verified, mainly when the H2 concentration was quite low. Basically, CD monoliths exhibited shorter ignition times compared to SC ones, due to the formation of spatially localized hot spots that promoted catalytic ignition. At the same time, the CD monoliths required shorter times to reach steady-state. But SC materials assured longer time on stream operations. The presence of the catalyst lined on both monoliths allowed reaching lower CO emissions. The best results belonged to the coated SiC monolith, with very low H2 concentration in the mixtures.