C2H6 Oxidation on Pt

Figure 4.33. Inverted volcano behaviour. Effect of catalyst potential and work function on the rate of C2H6 oxidation on Pt/YSZ. po2=107 kPa, pc2H6 65 kPa T=500°C , T=460°C , T=420°C.24 Reprinted with permission from Academic Press.

A fourth important case of r vs O dependence is the inverted volcano behaviour depicted in Figure 4.33 for the case of C2H6 oxidation on Pt/YSZ.24 The rate is enhanced by a factor of 7 for negative potentials and by a factor of 20 for positive ones. 

C2H6 oxidation on Pt has been investigated" in a single-pellet reactor at temperatures between 400 and 500°C. The reaction exhibits electrophobic behavior for positive currents (Vwr > V r ) and electrophilic behavior for negative currents (Vwr < V r ) (Figs. 37 and 38). In the former case, p is up to 20 and A up to 3(X). In the latter case, p is up to 7 and A up to -100. The open-circuit kinetic behavior indicates that the catalyst surface is predominantly covered with oxygen and that the cov-... 

Figure 3. Conversion, selectivity, and yield of ethylene formation by ethane oxidation on Pt coated alumina ceramic foam monoliths. Up to 70% C2H4 selectivity is obtained at -70% C2H6 conversion for a single pass yield of -55%. Addition of Sn to Pt increases the selectivity and alkane conversion significantly.

Figure 8.19. Scanning electron micrographs of the Pt-catalyst-electrode deposited on YSZ used for C2H6 oxidation.27 Reprinted with permission from Academic Press.

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