Ethylene silver-catalyzed direct oxidation

Example 6.12.1 Reaction mechanism of silver-catalyzed direct oxidation of ethylene (Rebsdat and Mayer, 2001 and Arpe, 2007). 

Ethylene Oxide. Essentially all ethylene oxide produced industrially is manufactured by the direct oxidation of ethylene catalyzed by silver 867,887-889... 

Although the main routes to propylene oxide formation are not based on direct catalytic oxidation of propylene, the direct epox-idation of propylene on silver would be financially preferable if high yield and selectivity to propylene oxide could be achieved. Similarly to ethylene oxidation on silver part of the undesirable byproduct CO2 comes from the secondary oxidation of propylene oxide (2,3). The kinetics of the secondary silver catalyzed oxidation of propylene oxide to CO2 and H2O have been studied by very few investigators (2). 

In the literature numerous studies exist on the kinetics and reaction network of the direct ethylene oxidation to ethylene oxide catalyzed by silver (see Example 6.12.1). The surface reaction is considered to proceed via the Langmuir-Hinshelwood mechanism (adsorption of ethylene and oxygen —> surface reaction desorption of ethylene oxide, see Section 4.5.2). The rate expression for the selective oxidation can be expressed in the following equation ... 

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