THE LUMINOUS MANTLE OF FUEL-RICH OXYACETYLENE FLAMES: II. FREE RADICAL AND CONTINUUM INTENSITIES, AND THEIR INFLUENCE ON C3 EMISSIONS

1957 ◽  
Vol 35 (11) ◽  
pp. 1275-1283 ◽  
Author(s):  
G. V. Marr
Keyword(s):  
Carbon Monoxide ◽  
Free Radical ◽  
Reaction Mechanisms ◽  
Experimental Error ◽  
Carbon Particle ◽  
Black Body ◽  
Reaction Scheme ◽  
Band Head ◽  
Ultraviolet Continuum ◽  
Background Continuum

The spectroscopic emissions from the luminous mantle of the oxyacetylene flame have been examined over a range of burning mixtures from 2.3 to 4.2 times stoichiometric. Plots of the band-head intensities for the radicals C2, C3, CH, and CN for different burning mixtures and for vertical traverses through the flame are reported. From a study of the variation of the background continuum from 3000 Å to 5200 Å with burning mixtures, the over-all continuum may be considered to consist of (a) a black-body carbon particle continuum having an energy distribution corresponding to a temperature of 2900 ± 200° K., (b) a continuum associated with the C3 radical emissions extending from 3500 Å to 4600 Å with a maximum at 4000 Å, and (c) an ultraviolet continuum extending from below 3000 Å to 5000 Å which appears similar to the carbon-monoxide flame continuum. Within the limits of experimental error the variation of the C3 bands and their associated continuum are identical. Possible reaction mechanisms for the production of the C3 emissions are considered and they probably may be accounted for by the reaction scheme[Formula: see text]

ChemInform Abstract: Free-Radical Carbonylation. Efficient Trapping of Carbon Monoxide by Carbon Radicals.

ChemInform ◽  
1990 ◽  
Vol 21 (19) ◽  
Author(s):  
I. RYU ◽  
K. KUSANO ◽  
A. OGAWA ◽  
N. KAMBE ◽  
N. SONODA
Keyword(s):  
Carbon Monoxide ◽  
Free Radical ◽  
Carbon Radicals

scholarly journals Gasification Pathways and Reaction Mechanisms of Primary Alcohols in Supercritical Water

2019 ◽  
Author(s):  
Brian Pinkard ◽  
John Kramlich ◽  
Igor V. Novosselov
Keyword(s):  
Free Radical ◽  
Supercritical Water ◽  
Reaction Mechanisms ◽  
Radical Reaction ◽  
Water Environment ◽  
Waste To Energy ◽  
Reaction Pathways ◽  
Free Radical Reaction ◽  
Reaction Products ◽  
Primary Alcohols

<div> <p></p><p>Supercritical water gasification is a promising waste-to-energy technology with the ability to convert aqueous and/or heterogeneous organic feedstocks to high-value gaseous products. Reaction behavior of complex molecules in supercritical water can be inferred through knowledge of the reaction pathways of model compounds in supercritical water. In this study methanol, ethanol, and isopropyl alcohol are gasified in a continuous supercritical water reactor at temperatures between 500 and 560 °C, and for residence times between 3 and 8 s. <i>In situ</i> Raman spectroscopy is used to rapidly identify and quantify reaction products. The results suggest the dominance of chain-branching, free radical reaction mechanisms that are responsible for decomposing primary alcohols in the supercritical water environment. The presence of a catalytic surface is proposed to be highly significant for initiating radical reactions. Global reaction pathways are proposed, and mechanisms for free radical reaction initiation, propagation, and termination are discussed in light of these and previously published experimental results.</p><br><p></p></div>

scholarly journals Gasification Pathways and Reaction Mechanisms of Primary Alcohols in Supercritical Water

2019 ◽  
Author(s):  
Brian Pinkard ◽  
John Kramlich ◽  
Igor V. Novosselov
Keyword(s):  
Free Radical ◽  
Supercritical Water ◽  
Reaction Mechanisms ◽  
Radical Reaction ◽  
Water Environment ◽  
Waste To Energy ◽  
Reaction Pathways ◽  
Free Radical Reaction ◽  
Reaction Products ◽  
Primary Alcohols

<div> <p></p><p>Supercritical water gasification is a promising waste-to-energy technology with the ability to convert aqueous and/or heterogeneous organic feedstocks to high-value gaseous products. Reaction behavior of complex molecules in supercritical water can be inferred through knowledge of the reaction pathways of model compounds in supercritical water. In this study methanol, ethanol, and isopropyl alcohol are gasified in a continuous supercritical water reactor at temperatures between 500 and 560 °C, and for residence times between 3 and 8 s. <i>In situ</i> Raman spectroscopy is used to rapidly identify and quantify reaction products. The results suggest the dominance of chain-branching, free radical reaction mechanisms that are responsible for decomposing primary alcohols in the supercritical water environment. The presence of a catalytic surface is proposed to be highly significant for initiating radical reactions. Global reaction pathways are proposed, and mechanisms for free radical reaction initiation, propagation, and termination are discussed in light of these and previously published experimental results.</p><br><p></p></div>

Stability of carbon monoxide oxidation process on gold nanoparticles

2020 ◽  
Vol 8 (1) ◽  
pp. 116-124
Author(s):  
P. P. Kostrobij ◽  
◽  
I. A. Ryzha ◽  
Keyword(s):  
Carbon Monoxide ◽  
Gold Nanoparticles ◽  
Reaction Mechanisms ◽  
Structural Changes ◽  
Oxidation Process ◽  
Lyapunov Method ◽  
Catalyst Surface ◽  
Carbon Monoxide Oxidation ◽  
One Step ◽  
The Stability

The stability conditions for mathematical models of carbon monoxide oxidation on the surface of gold nanoparticles are investigated. The cases of reaction mechanisms of one-step and step-by-step transformation of reagents are consecutively considered. Using the stability analysis by Lyapunov method, it is shown that models which take into account the possibility of structural changes of the catalyst surface can predict the occurrence of oscillatory mode in the system as a result of Hopf instability.

Strahlenchemie von Alkoholen XVII

1972 ◽  
Vol 27 (1) ◽  
pp. 41-46 ◽  
Author(s):  
C. v. Sonntag
Keyword(s):  
Carbon Monoxide ◽  
Molecular Hydrogen ◽  
Reaction Scheme ◽  
Quantum Yields ◽  
Effect Of Water ◽  
Formed Hydrogen

In the 185 nm photolysis of liquid O2-free isopropanol the following products (quantum yields) are formed: hydrogen (0.75), acetone (0.72), pinacol (0.036), methane (0.046), acetaldehyde (0.04), propane (0.02β), ane (0.0023) and carbon monoxide (0.0015). A detailed reaction scheme is proposed. The major primary processes are the formation of H-atoms by homolytic scission of the O —H-bond (61 — 69%), elimination of molecular hydrogen (21%) and molecular methane (5%). Φ(Η2) is strongly decreased by adding water which does not absorb an appreciable portion of the 185 nm light in the mixtures down to 1 mole/l isopropanol (Φ(Η2) =0.21). In contrast to the strong effect of water there is no effect on Φ(Η2) by diluting isopropanol with n-hexane. From experiments with isopropanol-OD and 2-deutero-isopropanol it is tentatively concluded that H-atoms stemming from the O—H-group of the alcohol are to about 65% the precursors of the hydrogen in these mixtures.

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