Copper surface oxidation studies

The kinetic study of antioxidant decay by the reaction with hydroperoxides produced by T-6 oxidation proved the catalytic influence of the copper surface. The rate of this reaction in the absence of dioxygen obeys the equation... 

In addition to peroxyl radicals and hydroperoxide, amines are oxidized by dioxygen and this reaction was found to be catalyzed by the copper surface also. This reaction was studied in chlorobenzene and occurs with the rate ... 

Ellis and coworkers studied the effect of lead oxide on the thermal decomposition of ethyl nitrate vapor.P l They proposed that the surface provided by the presence of a small amount of PbO particles could retard the burning rate due to the quenching of radicals. However, the presence of a copper surface accelerates the thermal decomposition of ethyl nitrate, and the rate of the decomposition process is controlled by a reaction step involving the NO2 molecule. Hoare and coworkers studied the inhibitory effect of lead oxide on hydrocarbon oxidation in a vessel coated with a thin fQm of PbO.P l They suggested that the process of aldehyde oxidation by the PbO played an important role. A similar result was found in that lead oxide acts as a powerful inhibitor in suppressing cool flames and low-temperature ignitions.P l... 

As mentioned above, all metal surfaces used in these studies contain an oxidic layer and non-specifically adsorbed surface contaminations. Even the copper surface contains an oxidic layer in the order of 1-2 nm thickness. The differences in the adsorption capacities of a metal and its corresponding metal oxide towards PVFA-co-PVAm were compared by means of Zn and ZnO as well as Fe and Fe2C>3. XPS was employed in order to determine the amount of the polyelectrolyte adsorbed onto the metal or metal oxide surface. XPS is a well established surface sensitive spectroscopic method with an information depth not higher than 10 nm. 

The results of studies of copper surfaces by low-temperature adsorption isotherms may be summarized as follows. True surface areas of metallic specimens as small as 10 sq. cm. can be derived with a precision of 6% from low-temperature adsorption isotherms using vacuum microbalance techniques. This method is of special value in determining the average thickness of corrosion films formed by the reaction of gases or liquids with solids. The effect of progressive oxidation of a rough polycrystalline metal surface is to decrease the surface area to a point where the roughness factor approaches unity. 

Allan and Mitchell (131) have also made some studies of the low-temperature oxidation of evaporated copper surfaces. They find the... 

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