Inert species influence kinetics

Many gas-phase reactions are carried out with the addition of a filler species, an inert gas that increases the pressure, collides with the reactants, and otherwise influences the course of the reaction. It is interesting to observe whether such an added inert species has an effect on the kinetic results. To the conditions of Example 8.2 add 500 E cells, which do not interact with the... 

The spillover effect can be described as the mobility of sorbed species from one phase on which they easily adsorb (donor) to another phase where they do not directly adsorb (acceptor). In this way a seemingly inert material can acquire catalytic activity. In some cases, the acceptor can remain active even after separation from the donor. Also, quite often, as shown by Delmon and coworkers,65 67 simple mechanical mixing of the donor and acceptor phases is sufficient for spillover to occur and influence catalytic kinetics leading to a Remote Control mechanism, a term first introduced by Delmon.65 Spillover may lead, not only to an improvement of catalytic activity and selectivity but also to an increase in lifetime and regenerability of catalysts. 

---