Peroxide dissociation

The diacyl peroxide dissociates to produce radicals, which in turn initiate chains. 

Dimethylsulfide accelerates the decomposition of tert-bntylperoxybenzoate (Pryor and Hendrickson 1983). Dimethylsulhde acts as a donor, whereas the peroxide acts as an acceptor. Strictly nnder the same conditions, the rate of the peroxide dissociation in the presence of Me2S is almost 1.5 times greater than that in the presence of ( 03)28 (Pryor and Hendrickson 1983). 

Both acids are detected in the atmosphere. Hydrogen peroxide dissociates into OH radicals by absorption of light below 3200 A [see Section V11—61... 

The photochemical oxidation reactions of unsaturated organic molecules lead to the formation of peroxides which are characterized by the weak bond O-O. In terms of bond energies this is one of the weakest covalent bonds weak enough to be split in thermal processes. When a cyclic peroxide dissociates into carbonyl compounds, one of these may be formed in an electronically excited state (Figure 4.83). The energy difference results from the loss of the weak 0-0 bond and the formation of two C=0 tt bonds over 60kcalmol-1 is then available as free energy. There are also reasons of... 

According to Nozari and Barlett s kinetic data [ 14], benzoyl peroxide dissociation competes with hemolytic decomposition and a reaction with free radical participation. The kinetic dissociation equation is as follows ... 

The basic typical difference is that at organic peroxide dissociation (e.g. di-/m-bu(yl peroxide, scheme (1.7)) a complex set of final products—alcohols, ketones, oxides, methane and other hydrocarbons—is formed, whereas from hydrogen peroxide only H20 and 02 are formed. 

Various types of possible interactions between reactions are discussed. Some of them are united by the general idea of chemical reaction interference. The ideas on conjugated reactions are broadened and the determinant formula is deduced the coherence condition for chemical interference is formulated and associated phase shifts are determined. It is shown how interaction between reactions may be qualitatively and quantitatively assessed and kinetic analysis of complex reactions with under-researched mechanisms may be performed with simultaneous consideration of the stationary concentration method. Using particular examples, interference of hydrogen peroxide dissociation and oxidation of substrates is considered. 

INTERFERENCE OF HYDROGEN PEROXIDE DISSOCIATION AND SUBSTRATE OXIDATION REACTIONS... 

Interference of Hydrogen Peroxide Dissociation and Substrate Oxidation Reactions... 

The primary reaction of conjugated dehydrogenation by hydrogen peroxide in the gas phase at 400-650 °C represents peroxide dissociation which generates active sites in the system ... 

The kinetics and mechanisms of the majority of these reactions were also studied. It is shown that successful application of hydrogen peroxide is promoted by a combination of high induction properties and effectiveness and specificity of action in it, accompanied by the harmlessness of hydrogen peroxide dissociation products. 

Analyzing the dependencies deduced, it may be concluded that the yield of oxygen formed at hydrogen peroxide dissociation decreases with the increase in methanol yield. 

Kinetics and the Mechanism of Synchronous (Interfering) Reactions of Hydrogen Peroxide Dissociation and Oxidation of Substrates in the Gas Phase... 

Actually, from an energy-gaining position, it is desirable to carry out such reactions conjugated with another reaction, which can be hydrogen peroxide dissociation. 

The scope of the experimental data allowed the determination of several kinetic regularities, among which the synchronized curves (Figure 5.2) are of special interest which demonstrate the induction effect of the primary reaction (hydrogen peroxide dissociation) on the secondary (inducible) reaction of CH4 hydroxylation. 

HYDROGEN PEROXIDE DISSOCIATION INTHE LIQUID PHASE... 

Figure 6.1 The mechanism of hydrogen peroxide dissociation in the Fenton system. The sketch is based on the data by Kazarnovsky [7], Haber-Weiss [9], Bard [6] and Uri [25].

In the framework of the theory of elementary open catalytic system self-development suggested by Rudenko [59] evolutionary changes in homogeneous catalytic systems based on hydrogen peroxide dissociation are indicated [60], Hence, it is suggested that formation of amino acids, for example, is associated with the transformation of components in the... 

In alkaline solution, hydrogen peroxide dissociates (Figure 2.4). 

The perhydroxyl ion, HO2, is formed by hydrogen peroxide dissociation in base ... 

Second protonation and 0-0- scission, peroxide dissociation-second uncoupiing... 

In the polymerization reactor, organic peroxides dissociate homolytically to generate free radicals. Polymerization of ethylene proceeds by a chain reaction. Initiation is achieved by addition of a free radical to ethylene. Propagation proceeds by repeated additions of monomer. 

This explanation, however, is no longer tenable. There is no absolute certainty about the nature of the bleaching action but it is believed that the perhydroxyl ion is the active species. These ions are formed when hydrogen peroxide dissociates in the following manner ... 

At wavelengths below 2300 A alkyl peroxides dissociate in another way namely,... 

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