Mechanism, of catalytic oxidation

Hoffmann, M. R., and D. J. Jacob, Kinetics and Mechanisms of Catalytic Oxidation of Dissolved Sulfur Dioxide in Aqueous Solution An Application to Nighttime Fog Water Chemistry, in SO2, NO, and N02 Oxidation Mechanisms Atmospheric Considerations, Acid Precipitation Series, Vol. 3, pp. 101-172 (J. I. Teasley, Series Ed.), Butterworth, Stoneham, MA, 1984. 

It is interesting that this mechanism, which was suggested during one of the early studies of tin-antimony oxides, has received so little subsequent attention, since it is a process that could be applied to some of the mechanisms of catalytic oxidation proposed in later studies. 

Dalai, A.K. and ToUefson, E.L. (1986). Kinetics and reaction mechanism of catalytic oxidation of low concentrations of hydrogen sulfide in natural gas over activated carbon. Can.J. Chem. Eng., 76, 902-14. 

Catalytic oxidative transformations of lower alkanes attract the attention as possible ways to transfer these substances into more suitable chemicals - olefins and oxygenates (alcohols, aldehydes, acids, etc.) - and to involve them into the industrial use as raw materials for chemical and petrochemical synthesis. However, the yields of desirable products reached up to date are not sufficiently high. The progress in the studies of intrinsic mechanism of catalytic partial oxidation of lower alkanes is not sustainable either. We believe that these two facts are correlated and that the analysis we performed in the present work can brighten up some important details of the mechanism of catalytic oxidation of lower alkanes. ... 

The discussion of the mechanism of catalytic oxidation falls into two extreme cases. (1) A pure auto-oxidation can be postulated wherein the oxygen is activated by the platinum and a peroxide intermediate is formed which decomposes to yield an aldehyde and hydrogen peroxide. 

Scientists working in catalysis were long ago concerned with the theory of reduction-oxidation mechanisms of catalytic oxidation reactions. 

In the oxidation of CH4 and CjHg, no inhibition by the reactant is operative, and initial conversion is higher near the reactor inlet, where favourable conditions for ignition are stabilized. This relationship between dynamic behaviour and adsortion-desorption properties, finds support in the literature. Site competition between hydrocarbons and oxygen has been recognized as a key point in the mechanism of catalytic oxidation [3] in the same study, a substantially different behaviour in catalytic combustion was reported for alkanes and ethylene, and this was related to the strong adsorption properties of the latter. 

As shown by Golodets (p. 289), the formation of the carbonate intermediate also may be interpreted in terms of the more conventional redox or Mars-van Krevelen cycle, which explicitly involves the oxidation and reduction of the metal oxide." The Mars-van Krevelen mechanism of catalytic oxidations over metal oxides is a redox mechanism involving both gas phase and lattice oxygen ... 

Although many attempts to examine the mechanism of catalytic oxidation have been reported, the exact mechanism even for intensely studied reactions such as CO oxidation is not completely understood. However, certain general statements about p-type oxides and V2O5 deep... 

Mechanism of catalytic oxidation of hindered phenols in the presence of various metal complexes... 

Considerable work has been expended on elucidating the mechanism of catalytic oxidation of hindered phenols. Reactions of this kind proved to be amenable to kinetic studies and structural work on isolated intermediates. Systems involving cobalt chelate complexes as catalysts have received much attention. In this section we discuss in some detail the most important mechanistic versions proposed thus far. 

Kobayashi, M., Kobayashi, H., 1972b. Application of transient response method to the study of heterogeneous catalysis II. Mechanism of catalytic oxidation of carbon monoxide on manganese dioxide. J. Catal. 

Haber J, Machej T, Janik R, Rrysciak J, Sadowska H. On the Mechanism of Catalytic Oxidation of CH2CI2 on y-Al203 and its Oscillatory Behavior. Z Phys Chem 1996 197 97-112. 

A detailed account of the mechanisms of catalytic oxidation processes has been published. The mechanisms of the catalytic oxidation of terminal oleffns to methyl ketones and of the catalytic epoxidation of olefins with hydroperoxides have also been reviewed. The latter reactions are generally thought to proceed via direct attack of the substrate upon an electrophilic oxygen of a metal peroxo species rather than prior complexa-... 

Scheme 2.8 Two General Mechanisms of Catalytic Oxidation by Transition Metal Catalysts.

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