Formation of Buffer Species

Formation of buffer species which block the sites and drive the system between low and high conversion states.  

Non-isothermal effects, due to sudden increase in catalyst temperature 

Surface migration of species and reaction taking place along the perimeter of islands of adsorbed species. 

It remains the case though that the experimental and simulation studies carried out have largely been conducted as parallel activities with little effort to date to compare the experimental transients with model predictions. 

An important class of model widely examined is that in which an inert buffer is formed on the surface and blocks the active sites available for CO oxidation. This could be a tightly bound O2 on the surface, also referred to as oxide in the literature, which does not react with adsorbed or gas-phase CO. There is then a dynamic equilibrium between the active and inactive forms of O2 [equation (8)]. 

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