Hydrogen Peroxide Dissociation Kinetics and the Mechanism

Before passing on to the analysis of gas-phase oxidation with hydrogen peroxide, we must first obtain information about its dissociation. Hydrogen peroxide easily dissociates to water and molecular oxygen, which is the typical feature, very useful in some cases and unwanted in another. H202 can dissociate in different ways, but all of them are described by the general material balance equation as follows  

Of importance for understanding kinetics and oxidation mechanism of various substrates with the participation of hydrogen peroxide are the conditions of H202 dissociation into intermediates. As already mentioned in early studies on heterogeneous gas-phase dissociation of H202 [3], the reaction is rather sensitive to the type of reactor walls and depends on their preparative treatment, which makes obtaining reproductive data more difficult. 

In later works [4], Satterfield and Stein note that in flow conditions up to 723 K the homogeneous component contribution into the reaction is low and the following H202 dissociation mechanism is suggested  

Of interest are works [5-9] showing that at increased temperature heterogeneous dissociation reaction transits to a homogeneous reaction and the reaction degree by H202 becomes equal to 1. 

Jigger and Li [60] have discovered that the transition zone is located at 673 K, and the effective rate constant of dissociation equals  

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