Spillover of oxygen species in the steam reforming of propane on ceria-containing catalysts

Several kinds of experiments were carried out to show that oxygen species (OH, O) can be transferred from a Rh/Al 2 O 3 (RhA) catalyst to pure oxides and vice-versa. Ceria physically mixed with RhA increases the catalytic activity of the Rh catalyst for the steam reforming of propane. Conversely, RhA can promote the exchange of 18 O 2 with the 16 O of pure oxides, normally inactive for the 18 O/ 16 O exchange in the absence of RhA. Moreover, large amounts of steam reforming products (H 2 , CO) were obtained by injecting pulses of pure propane over a PtRh/CeO 2 /Al 2 O 3 catalyst. OH groups stored on the support migrate to the metal particles where the reaction with CH x fragments (issued from the C 3 H 8 activation) can occur.

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