Thermal Decomposition of Hydrogen Peroxide in the Vapour Phase

Nature ◽  
1949 ◽  
Vol 163 (4153) ◽  
pp. 876-877 ◽  
Author(s):  
A. B. HART
2019 ◽  
Author(s):  
James Ewen ◽  
Carlos Ayestaran Latorre ◽  
Arash Khajeh ◽  
Joshua Moore ◽  
Joseph Remias ◽  
...  

<p>Phosphate esters have a wide range of industrial applications, for example in tribology where they are used as vapour phase lubricants and antiwear additives. To rationally design phosphate esters with improved tribological performance, an atomic-level understanding of their film formation mechanisms is required. One important aspect is the thermal decomposition of phosphate esters on steel surfaces, since this initiates film formation. In this study, ReaxFF molecular dynamics simulations are used to study the thermal decomposition of phosphate esters with different substituents on several ferrous surfaces. On Fe<sub>3</sub>O<sub>4</sub>(001) and α-Fe(110), chemisorption interactions between the phosphate esters and the surfaces occur even at room temperature, and the number of molecule-surface bonds increases as the temperature is increased from 300 to 1000 K. Conversely, on hydroxylated, amorphous Fe<sub>3</sub>O<sub>4</sub>, most of the molecules are physisorbed, even at high temperature. Thermal decomposition rates were much higher on Fe<sub>3</sub>O<sub>4</sub>(001) and particularly α-Fe(110) compared to hydroxylated, amorphous Fe<sub>3</sub>O<sub>4</sub>. This suggests that water passivates ferrous surfaces and inhibits phosphate ester chemisorption, decomposition, and ultimately film formation. On Fe<sub>3</sub>O<sub>4</sub>(001), thermal decomposition proceeds mainly through C-O cleavage (to form surface alkyl and aryl groups) and C-H cleavage (to form surface hydroxyls). The onset temperature for C-O cleavage on Fe<sub>3</sub>O<sub>4</sub>(001) increases in the order: tertiary alkyl < secondary alkyl < primary linear alkyl ≈ primary branched alkyl < aryl. This order is in agreement with experimental observations for the thermal stability of antiwear additives with similar substituents. The results highlight surface and substituent effects on the thermal decomposition of phosphate esters which should be helpful for the design of new molecules with improved performance.</p>


1968 ◽  
Author(s):  
K. R. Bilwakesh ◽  
W. A. Strauss ◽  
R. Edse ◽  
E. S. Fishburne

1947 ◽  
Vol 25b (2) ◽  
pp. 135-150 ◽  
Author(s):  
Paul A. Giguère

The decomposition of hydrogen peroxide vapour has been investigated at low pressures (5 to 6 mm.) in the temperature range 50° to 420 °C., for the purpose of determining the effect of the nature and treatment of the active surfaces. The reaction was followed in an all-glass apparatus and, except in one case, with one-litre round flasks as reaction vessels. Soft glass, Pyrex, quartz, and metallized surfaces variously treated were used. In most cases the decomposition was found to be mainly of the first order but the rates varied markedly from one vessel to another, even with vessels made of the same type of glass. On a quartz surface the decomposition was preceded by an induction period at low temperatures. Fusing the glass vessels slowed the reaction considerably and increased its apparent activation energy; this effect was destroyed by acid washing. Attempts to poison the surface with hydrocyanic acid gave no noticeable result. The marked importance of surface effects at all temperatures is considered as an indication that the reaction was predominantly heterogeneous under the prevailing conditions. Values ranging from 8 to 20 kcal. were found for the apparent energy of activation. It is concluded that the decomposition of hydrogen peroxide vapour is not very specific as far as the nature of the catalyst is concerned.


1937 ◽  
Vol 59 (2) ◽  
pp. 422-422 ◽  
Author(s):  
G. B. Kistiakowsky ◽  
S. L. Rosenberg

By mass-spectrometric analysis combined with vapour-phase chromatography the reaction products from the thermal decomposition of ether have been determined at various stages of the reaction (uninhibited and inhibited by nitric oxide) for initial ether pressures of 80 to 1000 mm. The effects of added hydrogen and of carbon tetrafluoride on the composition of the products have also been examined. No major changes in the chemistry of the reaction occur with these variations in conditions. Factors are given for calculating true rate constants from pressure changes accompanying the reaction. Corrected values of rate constants vary with the conditions in the same way as the values derived from uncorrected pressure changes, the correspondence being close for the uninhibited reaction.


Author(s):  
Jeremy Corpening ◽  
Stephen Heister ◽  
Willam Anderson ◽  
Benjamin Austin

2008 ◽  
Vol 47 (4) ◽  
pp. 279-285 ◽  
Author(s):  
J.V. Rogers ◽  
W.R. Richter ◽  
M.Q. Shaw ◽  
Y.W. Choi

1959 ◽  
Vol 55 ◽  
pp. 548 ◽  
Author(s):  
D. E. Hoare ◽  
J. B. Protheroe ◽  
A. D. Walsh

1991 ◽  
Vol 46 (2) ◽  
pp. 139-142 ◽  
Author(s):  
Markus Wieber ◽  
Udo Simonis ◽  
Dieter Kraft

The oxidation of dialkoxymethylstibine with hydrogen peroxide in the presence of sodium hydroxide leads to the formation of disodium-di-μ-oxo-bis[trihydroxo-methylantimonate(V)]. The salt can be synthesized also by dissolving methanestibonic acid in an aqueous solution of sodium hydroxide. The crystal structure has been determined; it shows a dimeric molecule containing a four-membered ring with Sb -O -Sb linkages. Thermal decomposition and spectroscopic properties o f the com pound are discussed.


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