Catalytic Decomposition Kinetics of Aqueous Hydrogen Peroxide and Solid Magnesium Peroxide By Birnessite

1992 ◽  
Vol 56 (6) ◽  
pp. 1784-1788 ◽  
Author(s):  
A. M. Elprince ◽  
W. H. Mohamed
Keyword(s):  
Hydrogen Peroxide ◽  
Catalytic Decomposition ◽  
Decomposition Kinetics ◽  
Aqueous Hydrogen Peroxide ◽  
Magnesium Peroxide ◽  
Kinetics Of

Measurement and Decomposition Kinetics of Residual Hydrogen Peroxide in the Presence of Commonly used Excipients and Preservatives

2009 ◽  
Vol 98 (11) ◽  
pp. 3987-3996 ◽  
Author(s):  
Victoria Towne ◽  
C. Brent Oswald ◽  
Robin Mogg ◽  
Joseph Antonello ◽  
Mark Will ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Decomposition Kinetics ◽  
Residual Hydrogen ◽  
Kinetics Of

Kinetics of the oxidation of dimethyl sulfoxide with aqueous hydrogen peroxide catalyzed by sodium tungstate

1981 ◽  
Vol 59 (4) ◽  
pp. 718-722 ◽  
Author(s):  
Yoshiro Ogata ◽  
Kazushige Tanaka
Keyword(s):  
Hydrogen Peroxide ◽  
Dimethyl Sulfoxide ◽  
Sodium Tungstate ◽  
Catalytic Amount ◽  
Active Oxygen ◽  
Probable Mechanism ◽  
Polarographic Study ◽  
Aqueous Hydrogen Peroxide ◽  
First Order ◽  
Kinetics Of

The oxidation of dimethyl sulfoxide (DMSO) by hydrogen peroxide in the presence of a catalytic amount of sodium tungstate (Na2WO4) has been studied kinetically by means of iodometry of hydrogen peroxide. The reaction is first-order with respect to the substrate and the catalyst, but independent of the concentration of hydrogen peroxide which is present in excess of the catalyst. The polarographic study implies that in solutions two main kinds of peroxytungstic acids (H2WO5 and H2WO8) are formed which contain active oxygen in ratios (active oxygen):(Na2WO4) of 1:1 and 4:1, respectively. The effect of acidity on the oxidation rate and a probable mechanism involving a rate-determining attack of peroxytungstic acids are discussed.

Kinetics of the Epoxidation of Crotonic Acid by Aqueous Hydrogen Peroxide Catalysed by Sodium Orthovanadatae

2012 ◽  
Vol 28 (3) ◽  
pp. 1475-1478
Author(s):  
J.V. SINGH ◽  
ANUPAM AWASTHI ◽  
DIPTI DIPTI ◽  
ASHISH TOMAR ◽  
DAVENDRA SINGH ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Crotonic Acid ◽  
Aqueous Hydrogen Peroxide ◽  
Kinetics Of

Oxywater-oxenoid conception of mechanisms of benzylpenicillin oxidation and oxidant decomposition in aqueous hydrogen peroxide solution

1970 ◽  
Author(s):  
Anton A. Chumakov ◽  
Oleg A. Kotelnikov ◽  
Yurij G. Slizhov ◽  
Tamara S. Minakova
Keyword(s):  
Hydrogen Peroxide ◽  
Oxygen Atom ◽  
Singlet Oxygen ◽  
Aromatic Ring ◽  
Hydrogen Peroxide Solution ◽  
Colloid Solution ◽  
Spin Moment ◽  
Aqueous Hydrogen Peroxide ◽  
True Nature ◽  
Kinetics Of

There are actuality and importance of confirmation or at least reasoned argumentation of molecular kinetics of hydrogen peroxide oxidation reactions because of currently unidentified true nature of oxygen intermediates, at one side, and widespread of these processes in natural biological and artificial anthropogenic systems, from other side. The building of common theory of hydrogen peroxide oxidative activity and dismutation decomposition can be based on determination of structure of individual model reactions products. The benzylpenicillin molecule has a heterofunctional structure. Its sodium salt was dissolved in aqueous hydrogen peroxide solution without Fenton catalysts addition. The system was protected from thermal and photochemical activation. As result, we observed a colloid solution formation, a water-insoluble sediment accumulation, and a hydrogen peroxide disproportionation with gas-phase molecular oxygen liberation. The NMR-spectroscopy data evidenced in favor of S-oxidation of sulfide fragment, N-oxidation of nitrogen atoms with amide groups dissociation, and aromatic ring hydroxylation and electrophilic carbonylation. The precipitate is a mixture of several substances, some of which have presumably an oligomeric structure due to neighboring molecules coupling in carbonylation and hydroxylamine fragments O-acylation reactions. The molecular kinetics of model organic molecule oxidative modifications and hydrogen peroxide dismutation is interpreted by oxywater-oxenoid conception. In accordance with one, there are different associates between water HOH and hydrogen peroxide HOOH molecules in solution system due to hydrogen bonds. These molecules are simultaneously Brønsted acids and bases. The rate of proton accepting and donation depends on temperature and concentration parameters. The hydronium H3O+ and hydroperoxonium H3O2+ cations, and the hydroxide HO− and hydroperoxide HO2− anions are generated. For hydrogen peroxide molecule H2O2, there is possibility for isomeric bipolar ion oxywater H2O+O− formation. The zwitter-ion heterolytically dissociates with water molecule liberation and singlet oxygen atom generation. The 1D-oxene (2p[↑↓][↑↓][_]) oxidizes sulfur and nitrogen heteroatoms through accepting their unshared electron pairs by own vacant atomic orbital. In addition, singlet oxygen atom hydroxylates an aromatic ring by hydride transfer and mediates decomposition of hydrogen peroxide. The dioxygen liberated during hydrogen peroxide dismutation is generated at first in singlet 1∆g-quantum state, the quenching of which, presumably, includes a dimerization of 1O2 antipodes by orbital moment. Inside the associate (1O2)2, the electron exchange interaction occurs. As result, two molecules of triplet dioxygen are generated, and they are antipodes by spin moment: first molecule has spin +1 and second molecule has spin −1.

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