Ethane Hydrogenolysis and Other Reactions

Contrast between Ethane Hydrogenolysis and Other Reactions 

Comparisons of the activities of various metal catalysts for reactions of hydrocarbons involving hydrogen as a reactant or product reveal activity patterns which are strongly dependent on the particular reaction considered. Several examples are discussed in the following subsections of this article. 

Summary of Kinetic Parameters for Ethane Hydrogenolysis on Copper-Nickel Alloys (74) 

6 Preexponential factor, molecules/sec cm2, in the equation r0 = r0 exp( —E/RT). c Order with respect to ethane. d Order with respect to hydrogen. 

Evidence for a marked difference between the surface and bulk compositions of dilute copper-nickel alloys has been reported recently by a number of investigators (82, 87-90). Much of the experimental evidence comes from hydrogen adsorption data (74, 82, 87, 90). The conclusions of van der Plank and Sachtler were based on the premise that nickel chemisorbs hydrogen while copper does not (82, 87). The total adsorption of hydrogen at room temperature was taken as a measure of the amount of nickel in the surface. However, in hydrogen adsorption studies on the catalysts used to obtain the catalytic results in Fig. 6, the amount of adsorption on the copper catalyst, while small compared to the adsorption on nickel, is not negligible (74) However, the amount of strongly adsorbed 

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IV. Contrast between Ethane Hydrogenolysis and Other Reactions. 106... 

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