Metal-oxygen bond strength, selectivity

Selectivity and Metal-Oxygen Bond Strength. The metal-oxygen bond strength could be measured as the differential heats of reoxidation of the reduced... 

VIII. A Generic Description of the Relationship between Metal-Oxygen Bond Strength and Selectivity... 

Sachtler and de Boer (136), following up ideas developed by Schenck and by Balandin regarding the importance of metal-oxygen bond strength for selective catalysis, measured the reduction rates of catalysts with hydrogen, and compared these to activities and selectivities in the oxidation of propylene to acrolein, using as a test mixture CjHg/Og/Ar = 1/2/5 at about 500°. Some results are collected in Table XIII. There... 

Metal-oxygen bond, 27 195, 196 insertion reactions, 28 136-141 strength and selectivity, oxidative dehydrogenation of alkanes, 40 26-28... 

Just as the previously cited work illustrated the role of matrix selection in the quality of the mass spectra, Mei and Harrison [40] studied the underlying equilibrium involved in the formation and removal of metal oxides from the spectra of compacted oxide samples. The analyte for these studies was La203, chosen because of the high affinity of lanthanum for atomic oxygen, a product of the dissociation of both residual air and water vapor in compacted samples. Because the La-O bond strength is very high (8.30 eV), this oxide represents a case in which the dissociation of the original analyte would be difficult as well. On the basis of previous studies [41], it was assumed that approximately 50% of the lanthanum species sputtered from the surface would be free La atoms, and the other half would exist as oxides of one form or another. 

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