Methanol Dehydrogenation on Ag and Pt

This causes a 380% increase in rn2co and a 413% increase in rCo- The corresponding enhancement factors are AH2co=-17.5, ACo=-3. There is also a 190% increase in r H4 with an enhancement factor ACh4= 0.3, but this rate increase has been shown56 to be Faradaic and due to the electrocatalytic reaction  

A qualitatively similar behaviour has been observed during CH3OH dehydrogenation on Pt at temperatures between 400° and 500°C, where enhancement factors A of the order of -10 were measured.58 

The hydrogenation of CO and C02 on transition metal surfaces is a promising area for using NEMCA to affect rates and selectivities. In a recent study of C02 hydrogenation on Rh,59 where the products were mainly CH and CO, under atmospheric pressure and at temperatures 300 to 500°C it was found that CH4 formation is electrophobic (Fig. 8.54a) while CO formation is electrophilic (Fig. 8.54b). Enhancement factor A values up to 220 were 

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